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The R-value of standard decking material used is 1. For suspended ceilings, an R-value of 0. The standard insulating materials considered over the roofs along with the R-values are given in Table 4.

Table 4. Insulation 1 in. For accomplishing this, the R-value of the roof can be input to the system for calculations. The estimation of heat losses through walls is similar to that of heat looses through roofs except that the wall materials used are different. In addition to these the insulating materials used are similar to those used on roofs. The common wall materials used in building construction are listed along the R-values in Table 4.

For heat loss calculations the inside and outside still air should also be considered. Sometimes, the temperatures in adjacent spaces can be different, therefore, temperatures adjacent to each of the walls is considered. Finally, the sum of heat losses or gains through each of the walls gives the heat loss through the four walls.

The R-value of a wall or roof structure that involves layers of uniform thickness is determined easily by simply adding up the unit thermal resistances of the layers that are in series. The overall R-value in these cases is determined by assuming 1 parallel heat flow paths through areas of different construction or 2 isothermal planes normal to the direction of heat transfer [29].

Building components often involve trapped air spaces between various layers. Thermal resistances of such air spaces depend on the thickness of the layer, the temperature difference across the layer, the mean air temperature, the emissivity of each surface, the orientation of the air layer, and the direction of heat transfer.

An approximate R-value of 0. For the estimation of heat load these values have been assumed. This is conduction heat transfer because of the direct contact between the walls and the floor, and it depends on the temperature difference between the basement and the ground, the construction of walls and the floor, and the thermal conductivity of the surrounding earth. There is considerable uncertainty in the ground heat loss calculations, and they probably constitute the least accurate part of heat load estimates of a building because of the large thermal mass of the ground and the large variation of the thermal conductivity of the soil, depending on the composition and moisture content [27].

These walls are based on a soil thermal conductivity of 0. It can be seen that the heat transfer coefficient values decrease with increasing depth since the heat at a lower section must pass through a longer path to reach the ground surface.

The interior air temperature of the basement can vary considerably, depending on whether it is being heated or not. Heat loss through the basement floor is much smaller since the heat flow path to the ground surface is much longer in this case. Where Ufloor is the overall heat transfer coefficient at the basement floor whose values are listed in table 4. Heat losses from the water heater and the space heater located in the basement usually keep the air near the basement ceiling sufficiently warm.

Heat losses from the rooms above to the basement can be neglected in such cases. This will not be the case, if the basement has windows [27]. Many residential and commercial buildings do not have a basement, and the floor sits directly on the ground at or slightly above the ground level.

Where Ugrade represents the rate of heat transfer from the slab per unit temperature difference between the indoor temperature Tindoor and the outdoor temperature Toutdoor and per unit length of the perimeter Pfloor of the building. Typical values of Ugrade are listed in table 4. It can be observed from the table that perimeter insulation of slab-on-grade reduces heat losses considerably, and thus it saves energy while enhancing comfort.

This is also the case when basement board heaters are used on the floor near the exterior walls. Heat transfer through the floors and the basement is usually ignored in cooling load calculations. In a building envelope, windows offer the least resistance to heat flow.

In a typical house, about one-third of the total heat loss in winter occurs through the windows [27]. Also, most air infiltration occurs at the edges of the windows. The solar heat gain through the windows is responsible for much of the cooling load in summer. The net effect of a window on the heat balance of a building depends on the characteristics and orientation of the window as well as the solar and weather data.

Workmanship is very important in the construction and installation of windows to provide effective sealing around the edges while allowing them to be opened and closed easily. Despite being so undesirable from an energy conservation point of view, windows are an essential part of any building envelope since they enhance the appearance of the building, allow daylight and solar heat to come in, and allow people to view and observe without leaving their home.

For low-rise buildings, windows also provide easy exit areas during emergencies such as fire. Important considerations in the selection of windows are thermal comfort and energy conservation. A window should have a good light transmittance while providing effective resistance to heat flow [27]. The lighting requirements of a building can be minimized by maximizing the use of natural daylight. Heat gain and thus cooling load in summer can be minimized by using effective internal or external shading on the windows.

Even in the absence of solar radiation and air infiltration, heat transfer through the windows is more complicated than it appears to be.

This is because the structure and properties of the frame are quite different than the glazing. The corresponding U-factors are given in Table 4. These are the factors which contribute to the thermal resistance by the glass area.

The frame area needs to be considered separately. The different types of frames available are generally made up of aluminum, and wood or vinyl. The frame material U- factors for fixed vertical windows for the type of windows discussed above are given in Table 4. The result is a double pane window, which has become the norm in window construction [27]. This uncontrolled entry of outside air into a building through unintentional openings is called infiltration, and it wastes a significant amount of energy since the air entering must be heated and cooled in summer.

The warm air leaving the house represents energy loss. This is also the case for cool air leaving in summer since some electricity is used to cool that air. That is, about one-third of the heating bill of such a house is due to the air leaks [27]. The rate of infiltration depends on the wind velocity and the temperature difference between the inside and the outside, and thus it varies throughout the year.

The infiltration rates are much higher in winter than they are in summer because of the higher winds and larger temperature differences in winter. Therefore, distinction should be made between the design infiltration rate at design conditions, which is used to size heating or cooling equipment, and the seasonal average infiltration rate, which is used to properly estimate the seasonal energy consumption for heating or cooling.

Infiltration appears to be providing " fresh outdoor air" to a building, but it is not a reliable ventilation mechanism since it depends on the weather conditions and the size and location of the cracks [27].

The air infiltration rate of a building can be determined by direct measurements by 1 injecting a tracer gas into a building and observing the decline of its concentration with time or 2 pressurizing the building to 10 to 75 Pa gage pressure by a large fan mounted on a door or window, and measuring the air flow required to maintain a specified indoor-outdoor pressure difference.

The larger the airflow to maintain a pressure difference, the more the building may leak [27]. Despite their accuracy, direct measurement techniques are inconvenient, expensive, and time consuming. A practical alternative is to predict the air infiltration rate on the basis of extensive data available on existing buildings. This is known as Crack method. Item Infiltration Windows 0.

This is called air change method, and the infiltration rate in this case is expressed in terms of air changes per hour ACH. A minimum of 0. Usually the infiltration rates of houses are above 0. It may be necessary to install a central ventilating system in addition to the bathroom and kitchen fans to bring the air quality to desired levels [27].

Venting the cold outside air directly into the house will obviously increase the heating load in winter. Such heat exchangers are commonly used in superinsulated houses, but the benefits of such heat exchangers must be weighed against the cost and complexity of their installation. The primary cause of excessive infiltration is poor workmanship, but it may also be the settling and aging of the building.

Infiltration is likely to develop where two surfaces meet such as the wall-foundation joint. Large differences between indoor and outdoor humidity and temperatures may aggravate the problem. Wind exerts a dynamic pressure on the building, which forces the outside air through the cracks inside the building.

Infiltration should not be confused with ventilation, which is the intentional and controlled mechanism of airflow into or out of a building. Ventilation can be natural or forced or mechanical , depending on how it is achieved. Ventilation accomplished by the opening of windows or doors is natural ventilation, whereas ventilation accomplished by an air mover such as a fan is forced ventilation.

Forced ventilation gives the designer the greatest control over the magnitude and distribution of airflow throughout a building.

The airtightness or air exchange rate of a building at any given time usually includes the effects of natural and forced ventilation as well as infiltration. Air exchange, or the supply of fresh air, has a significant role on health, air quality, thermal comfort, and energy consumption.

Therefore, the rate of fresh air supply should be just enough to maintain the indoor air quality at an acceptable level. The infiltration rate of older buildings is several times the required minimum flow rate of fresh air, and thus there is a high- energy penalty associated with it.

Infiltration increases the energy consumption of a building in two ways: First, the incoming outdoor air must be added or cooled in summer to the indoor air temperature. Second, the moisture content of outdoor air, in general, is different than that of the indoor air, and thus the incoming air may need to be humidified or dehumidified. The latent heat load is particularly significant in summer months in hot and humid regions such as Florida and coastal Texas.

In winter, the humidity ratio of outdoor is usually much lower than that of indoor air, and the latent infiltration load in this case represents the energy needed to vaporize the required amount of water to raise the humidity of indoor air to the desired level.

For the system developed, the rate of air infiltration is taken as cfh when the doors open and close infrequently. For this amount of air the sensible and latent components of infiltration load can be estimated similarly as given by equations 4. Database files door. As shown in fig 4. The Expert system asks the User about the location where the Space heat load is to be estimated so that the winter design temperature at that location can be used as the Outdoor temperature.

Based on the input variables, the expert system retrieves the data stored in the database files and estimates each of the Space heat load components. Finally, the indoor and outdoor design along with the heat load components in the form of output is available for the User. The Output can be selected in three different types for analysis and design of Heating System. An estimation of heating load in Atlanta is taken into consideration where a building is having a wall construction by 12 in.

Concrete block, an area of four walls as Sq. Also, an insulation of 1. For On-grade basement heat calculations, a poured concrete wall with severe conditions having a perimeter of Sq. Ft is used. A triple pane window area of Sq. Ft is used for estimation of heat losses through fenestration. For the Problem stated for estimation of space load, the expert system is consulted.

Once the User, usually a plant personnel having knowledge about Building construction and equipment installation is ready for consultation with the Expert system, the User can execute loadex. The following screen appears on the VP-Expert. After running the program, the expert system asks for the indoor design temperature that is required for the Space.

A temperature of 72 deg. For the estimation of outdoor design temperature, based on the weather data for 40 different locations throughout United States Figure 4.

For the present problem a heating system is to be Fig. Designed in the vicinity of Atlanta, Georgia. When the User enters the number corresponding Atlanta, Georgia which is 10, the average winter outdoor temperature is displayed. The expert system then proceeds with the details of Wall Construction to estimate the heat losses through walls.

Figure 4. The expert system developed can also be used when adjacent room temperatures are different. If there is any equipment that generates heat or uses heat, the User has the option to enter the temperature adjacent to that wall.

This indicates that there is heat gain through Wall 4 giving a net heat loss is — In other words there is heat gain instead of heat loss when one of the adjacent spaces is at a high temperature. The roofing parameters are requested by the expert system for the estimation of heat losses through the roof as shown in figure 4.

After estimating the heat losses through the walls and the roof, the expert system then proceeds for the estimation through on-grade floors or below grade basements. For this, the user is to select the type of basement for the space as shown in fig. The Expert system requests the user information about the On-grade floors. A poured concrete wall in a location having severe weather Fig. Conditions and no on grade floor insulation of perimeter ft.

The remaining consultation deals with window conduction heat losses as solar heat gain is not considered in the determination of design heat load which usually occurs in the earlier part of the day.

The User has to furnish details about the window frame and window glass types and areas for the estimation of heat losses. The window heat losses are as shown in Figure 4. The Infiltration load is calculated using the crack length method. For accommodating negative pressures that can occur due to infrequent opening and closing of doors, the user can input whether there is infrequent operation of doors.

The amount of air infiltrating due to infrequent opening and closing of doors is assumed to be cu. Ft per hour [26]. Also, in the calculation of latent heat load for infiltration, which is the heat, required to humidify the outdoor air, the relative humidity of indoor and outdoor air is taken as 0. The Total heat load estimated by the Expert System is The results are obtained by using the same building parameters and dimensions at all the locations with an indoor design temperature of 72 deg.

F as exemplified during the expert system consultation as discussed in the previous section. These results are given in Table 4. F IndianaPolis -2 Boston -6 Dallas 18 Memphis 13 Syracuse -3 San Francisco 35 As can be seen from the histogram, the maximum heat load occurs in that location where there is a very low average outdoor temperature in winter. In Boston, the average winter outdoor temperature is —6 deg. F, hence a larger amount of heating capacity is required to heat a building in Boston than the heat required to heat the same type of building in San Francisco.

Also, from figure 4. To deg. F Figure 4. Fenestration and Infiltration heat loads form the next major part and heat transmission through basement walls and floors appears to be less important. Also, with the use of an expert system, we are able to consider the possible heat losses through adjacent spaces if the spaces are at different temperatures. This is one of the features of Expert systems that can be very useful sometimes. Another point that can be noted is the Expert System accomodation of negative pressure in the Infiltration losses.

The cooling load details are discussed first and then the expert system consultation and results are exemplified. Loads are the heat that must be supplied or removed by the HVAC equipment to maintain a space at the desired conditions.

The calculations are like accounting [28]. One considers all the heat that is generated in the space or flows across the envelope; the total energy, including the thermal energy stored in the space, must be conserved according to the first law of thermodynamics. The principal terms are indicated in fig. Outdoor air, occupants, and possibly certain kinds of equipment contribute both sensible and latent heat terms. Load heat Conduction roof, walls, glazing supplied Conduction ground or Space removed Air exchange, sens.

Heat gain is the rate at which energy is transferred to or generated within a space. It has two components, sensible heat and latent heat, which must be computed and tabulated separately. The Cooling load is the rate at which energy must be removed from a space to maintain the temperature and humidity at the design values. While considering heavy constructed buildings, the cooling load will generally differ from the heat gain because the radiation from the inside surface of walls and interior objects as well as the solar radiation coming directly into the space through openings does not heat the air within the space directly.

Only when the room air receives the energy by convection does this energy become part of the cooling load [29]. For most purposes and for reasonable estimation, the sum of all the heat gains can be considered as the Cooling load.

The heat extraction rate is the rate at which the energy is removed from the space by the cooling and dehumidifying equipment. Again it is not reasonable to design for the worst conditions on record because a great excess of capacity will result. The daily range of temperature given in table 4. The daily range is usually larger for the higher elevations, where temperatures may be quite low late at night and during the early morning hours.

The daily range has an effect on the energy stored by the structure. The designer should be alert for unusual circumstances that may lead to uncomfortable conditions. Certain activities may require occupants to engage in active work or require heavy protective clothing, both of which would require lower design temperatures [29]. The primary sources are computers, printers, and copiers. Typical rates of heat dissipation by people are given in Table 5.

Note that the latent heat constitutes about one-third of the total heat dissipated during resting, but rises to almost two-thirds of the level during heavy physical work. Also, about 30 percent of the sensible heat is lost by convection and the remaining 70 percent by radiation [27]. The radiative sensible heat, on the other hand, is first absorbed by the surrounding surfaces and then released gradually with some delay. Heat given off by people usually constitutes a significant fraction of the sensible and latent heat gain of a building, and may dominate the cooling load in high occupancy buidlings.

The rate of heat gain from people in table 5. The design-cooling load of a building is determined assuming full occupancy. In the absence of better data, the number of occupants can be estimated on the basis of one occupant per 1 m2 in auditoriums, 2.

The rate of heat gain at any given moment can be quite different from the heat equivalent of power supplied instantaneously to those lights [26]. Only part of the energy from lights is in the form of convective heat, which is picked up instantaneously by the air-conditioning apparatus [26]. The remaining portion is in the form of radiation that affects the conditioned space once it has been absorbed and re-released by the walls, floors, furniture, etc.

This absorbed energy contributes to space cooling load only after a time lag, so part of this energy is reradiating after the lights have been switched off [26]. The primary source of heat from lighting comes from the light-emitting elements, or lamps, although significant additional heat may be generated from associated components in the light fixtures housing such lamps. The ratio of the lighting wattage in use to the total wattage installed is called the use factor, and it must be considered when determining the heat gain due to lighting at a given time since installed lighting does not give off heat unless it is on.

For commercial applications such as stores, the use factor would generally be unity [27]. Improper installation or design of lighting systems can have apparent HVAC implications. Many lighting fixtures serve as return air ducts, an integral part of the heating, ventilating and air conditioning system.

There are several considerations in HVAC systems that can drastically affect a building operation expenses as well as occupant comfort. Reduced lighting causes a corresponding reduction in the cooling load for the air conditioning equipment, especially in the interior zones, where outdoor conditions have little influence.

Demand for winter space heating may increase incrementally with reduced building lighting. This decreases the savings from the light reduction program by the amount of energy that must be added to offset the loss of heat. For example, in a terminal reheat system, a change in lighting could require as much additional energy to reheat the duct air as is saved by reducing the lighting [35]. The reheat requirement, however, can be minimized by raising the cool supply air temperature so comfort conditions in the room with the maximum cooling load are satisfied without reheating the air going to other rooms.

In the variable air volume system, a reduced cooling load would reduce the amount of cool air that is distributed through the building. This reduction may present an opportunity to replace the supply fan motors with smaller motors, saving additional energy. An HVAC expert is necessary to evaluate the retrofit savings potential [35]. For a fan, for example, part of the power consumed by the motor is transmitted to the fan to drive it, while the rest is converted to heat because of the inefficiency of the motor.

The fan transmits the energy to the air molecules and increases their kinetic energy. But this energy is also converted to heat as the fast- moving molecules are slowed down by other molecules and stopped as a result of friction [27]. Therefore, we can say that the entire energy consumed by the motor of the fan in a room is eventually converted to heat in that room. The power rating Wmotor on the label of a motor represents the power that the motor will supply under full load conditions.

But a motor operates at part load, sometimes at as low as 30 to 40 percent, and thus it consumes and delivers much less power than the label indicates. Also, there is inefficiency associated with the conversion of electrical energy to rotational mechanical energy. Therefore, it is not a good idea to oversize the motors since oversized motors operate at a low load factor and thus lower efficiency. Another factor that affects the amount of heat generated by a motor is how long a motor operates.

Motors with very low usage factors of dock doors can be ignored in calculations. If electric motor load is an appreciable portion of cooling load, the motor efficiency should be obtained from the manufacturer. The tremendous variety of appliances, applications, usage schedules, and installations, makes estimates very subjective. Electric typewriters, calculators, checkwriters, teletype units, posting machines, etc.

Table 5. Computer rooms housing mainframe or minicomputer equipment must be considered individually. Computer manufacturers have data pertaining to various individual components. In addition, computer schedules, near-term future planning, etc. While the trend in hardware development is toward less heat release on a component basis, the associated miniaturization tends to offset such unitary reduction by a higher concentration of equipment [27].

Temperature tb may range widely from the conditioned space. Actual temperatures in adjoining spaces should be measured when possible. Infiltration, exfiltration, and natural ventilation airflows are caused by pressure differences due to wind, indoor-outdoor temperature differences, and appliance operation [26]. Outdoor air must be introduced to ventilate conditioned spaces.

Local codes and ordinances frequently specify ventilation requirements for industrial installations. Generally, outdoor air for ventilation is introduced at the air-conditioning apparatus rather than directly into the conditioned space [26]. Fenestration components include: 1 glazing material, either glass or plastic; 2 framing; 3 external shading devices; 4 internal shading devices, and 5 integral between-glass shading systems.

The total instantaneous rate of heat gain through a glazing material can be obtained from the heat balance between a unit area of fenestration and its thermal environment. Solar radiation that is transmitted indoors is partially absorbed and partially reflected each time it strikes a surface, but all of it is eventually absorbed as sensible heat by the furniture, walls, people, and so forth.

Therefore, the solar energy transmitted inside a building represents a heat gain for the building. Also, the solar radiation absorbed by the glass is subsequently transferred to the indoors and outdoors by convection and radiation. The sum of the transmitted solar radiation and portion of the absorbed radiation that flows indoors constitutes the solar heat gain of the building [27]. The heat gains through sunlit double-strength sheet glass are designated as solar heat gain factors SHGF.

The Solar heat gain factors are based on terrestrial measurements [26] which represent solar intensity. These data do not give the maximum value of solar intensity that can occur in a year, but rather are representative of conditions on average cloudless days. The data for the month of August is being used because it is observed that Peak design cooling loads occur in August. Also, the times that have been considered for estimation of cooling load are AM, Noon, PM and PM, which are the usual daylight solar times in which peak loads occur.

For dates, times and latitudes other than those considered, linear interpolation can be used. It differs primarily as a function of the mass and nature of wall or roof construction, since those elements affect the rate of conductive transfer through the composite assembly to the interior surface [26].

Sol-air temperature is the temperature of the outdoor air that, in the absence of all radiation changes, gives the same rate of heat entry into the surface as would the combination of incident solar radiation, radiant energy exchange with the sky and other outdoor surroundings, and convective heat exchange with the outdoor air [26].

The sol-air temperatures for July 21, are given in table 5. The values correspond to a solar time of as it is known from observation peak load occurs in late afternoon. For walls and roofs the heat gains are estimated using the table 5. For determining the thermal resistance for the surfaces, the R-values of the materials of the surfaces of roofs and walls are used as discussed in the development of second module in chapter 4.

Orientation of Sol-air temp. For estimating heat gains the procedure is similar to the estimation of heat losses except that in place of Outdoor temperature, the sol-air temperature is used in the temperature difference term. In the present system developed Heat gain from miscellaneous sources is not dealt with. These parameters require analyzing system performance as a sequence if individual psychrometric processes [26].

An economizer system is a mixed air control system that utilizes outdoor air as the first stage of cooling to reduce energy usage. Most commercial buildings generally have a cooling requirement even during mild and cold weather conditions, because of the internal loads.

A cooling system with an economizer can use cool outside-air to satisfy all or part of the cooling demand. This reduces the cooling energy required by the system. A properly designed economizer will have no impact on the heating energy used by the building. Economizers use controllable dampers to increase the amount of outside-air intake into the building when the outside-air is cool and the building requires cooling.

In addition to the controllable outside-air dampers, there are several other key components in an economizer system: return-air dampers, exhaust air dampers, economizer controller, temperature controller, and minimum position limiter.

In addition, the relief- or exhaust-air dampers are required to prevent the building from being over-pressurized when large amounts of outside-air are introduced.

This controller arbitrates when to use outside-air for cooling and how much to use. It is required to provide the correct amount of outside air, while preventing the economizer from inadvertently increasing heating or cooling loads by introducing more outside-air than required.

It is implemented by sensing and controlling how cold the mixed-air or supply air temperature gets. It overrides the economizer controller, limiting the amount of cold outside air, to prevent coil freezing and uncomfortably cold drafts in conditioned spaces during cold weather. Minimum Position limiter- When outside-air conditions are not favorable for economizing, the outside-air damper system is positioned to provide the minimum outside-air intake required to meet the fresh air ventilation requirements for occupants.

The control strategies employed in economizer systems are differential dry- bulb temperature based, differential enthalpy-based, high-limit dry-bulb temperature- based, and high-limit enthalpy-based. With differential control strategies, the outside- air condition is compared with the return-air condition. As long as the outside-air condition is more favorable for example, with dry-bulb temperature control the outside-air dry-bulb temperature is less than the return-air temperature , outside-air is used to meet all or part of the cooling demand.

If the outside-air alone cannot satisfy the cooling demand, mechanical cooling is used to provide the remainder of the cooling load.

With high-limit control strategies, the outside-air condition is compared to a single set point or fixed set point usually referred to as a high limit. If the outside air condition is below the set point, then outside-air is used to meet all or part of the cooling demand; the remainder of the cooling load is provided by mechanical cooling.

Dry bulb economizers only control the outside air dampers based on temperature. If it is a cool but rainy day, the outside air will be brought in and extra cooling capacity will be required to dehumidify it. Hence, dry bulb temperature economizers would be suitable for dry and arid climates.

Enthalpy economizers take temperature and humidity into account. With enthalpy control, humid air below a conventional dry bulb setpoint is locked out. Cooling costs are lowered in most climates when using enthalpy instead of dry bulb temperature with the economizer [43].

There are two enthalpy control strategies available: single and differential dual sensor enthalpy control. The single enthalpy control uses one enthalpy sensor located in the outdoor air in any orientation that exposes it to freely circulating air and protects it from rain, snow and direct sunlight.

The enthalpy sensor replaces the dry bulb high limit used in a standard economizer. Instead of switching the mixed air control loop from outdoor air-dry bulb temperature, on a call for cooling from the controller or space thermostat the economizer logic module compares the outdoor enthalpy to a preselected setpoint. The value of the setpoint is illustrated on the psychrometric chart in the fig 5. The setpoint selected will vary based on climate, activities in the controlled area and the type of mechanical equipment used to provide cooling.

An installer can choose a more aggressive setpoint A for more free cooling or a conservative setpoint D for less free cooling. Each setting corresponds to an enthalpy curve with A equalling the highest enthalpy changeover and D being the lowest enthalpy. The output of the controller can be used to switch the mixed air and back as required for maximum efficiency.

The psychrometric chart shows effects of the various economizer logic setpoints listed in table 5. Air to the left of the Curve is brought in from outdoors to be used for cooling. Outdoor air to the right of the curves is not used.

For differential enthalpy the setpoint knob is turned past D setting and the lower of return or outside air is brought into the building. F B 70 deg. F C 67 deg. F D 63 deg. This is also referred to as differential enthalpy. The air with lower enthalpy, outdoor or return, is selected to be brought into the conditioning section of the air handler. The setpoint on the controller is turned to D whenever differential enthalpy is used [43]. This is a very efficient method of controlling outdoor air usage since the return and outside air is continuos and automatic year-round.

It eliminates operator error by eliminating seasonal changeover that is frequently overlooked. Though it may appear wasteful to cool outdoor air at a higher dry bulb temperature than return air, the fact is that the amount of mechanical cooling required to dehumidify air often exceeds the amount required to lower the dry bulb temperature. In buildings where there is moisture-generating activity this type of control sequence can result in substantial savings in cooling costs.

Figure 5. At low outdoor air temperatures, relatively little air is needed whereas at mild temperatures, a great deal of outdoor air is needed to meet the cooling load.

Of course, at still higher temperatures, outdoor air can no longer be used for cooling, and the mechanical cooling system will operate. Also, a part of the return is used. This is done to provide sufficient airflow circulation within building spaces. The amount of outdoor air needed, by itself, is insufficient to maintain comfortable air circulation under all conditions [28].

For estimating the energy savings there are certain technical details which have to be noted usually from the name plate of the cooling system. The energy savings are obtained based on the enthalpy of the outside air. Department of Energy Weather data can be used to generate enthalpy readings for each hour per month based on the outdoor temperature and the location where economizer usage is to be tested.

The enthalpy readings for each hour per month are given in Table 5. The enthalpy is a function of the dry bulb temperatures and the humidity. The higher the dry bulb temperatures and humidity levels the larger the enthalpy value.

The enthalpy can also be determined directly from a Psychometric Chart. In order to do this, the user needs either the dry bulb temperature and the humidity or both the wet bulb temperatures and the dry bulb temperatures. The energy efficiency ratio EER is the ratio of heating capacity Btu per hour to the electric input rate watts.

EER thus has the units of Btu per watt per hour. For obtaining the enthalpy readings we can use the weather data supplied by the DOE for other major locations and extract the enthalpy readings based on standard guidelines provided by the Department of energy [3]. This part of the Chapter is to make the User run through the Expert system for the estimation of Cooling Load. After the estimation of solar heat gain, the expert system proceeds to calculate the heat gains from the walls and roof based on the Sol-air temperature.

Since, the form of input is same as that in chapter 4 the screens are not presented in this chapter and the next part of consultation is shown in fig. The User has to select the number and type of occupancy during the consultation. By type of occupancy, it is meant the degree of activity inside the space or the building that can contribute to the heat gain.

As different spaces would involve different activity and the energy released during different activities is different, the heat gain is influenced by the degree of activity. The heat gain due to various kinds of office equipment is selected and heat estimated by the System. Various kinds of office appliances used are listed by the expert system and the user can select accordingly. Also, the internal heat gain due to motor driven equipment and lights is also estimated by the system. In this part of the consultation, it is important to know certain parameters like the time of operation of equipment and lights.

The form of input and the screens are the same for conduction heat gain through glass and infiltration heat gains as in the Heat load estimation. Also, a minimum total of 5-ton Cooling Capacity will be required to retrofit an Economizer. The Economizer input and the energy savings in MMBtu is furnished by the Expert system which can be used for estimating the cost savings based on the cost of electricity. It can be seen from the figure that with the increase in the Outdoor temperature, the cooling load The Graph shown also gives an idea about using outside air cool air.

During the cooling season, one can get rid of heat gains and postpone the onset of cooling by opening the windows or increasing the ventilation which is also termed as operating in economizer mode. The conditioner is needed only when the outdoor temperature goes beyond the threshold Tmax. F Figure 5.

Further, the functioning of the system necessary to estimate the cooling load is presented. It can be concluded that in the Cooling Load analysis, transmission heat gains contribute to the maximum heat gain.

The motor driven equipment and the internal heat gain sources are the next major part of the cooling load. Determination of Cooling load is important for efficient use of Cooling systems. The Use of economizers in most climates brings about good amount of savings, as the cooling system does not operate in the economizer mode. Validation is the process of determining that the system actually fulfills the purpose for which it was intended.

That is, substantiating a system or model performs with an acceptable level of accuracy. Initially, validation efforts were informal and highly individualized often characterized as a "craftsman approach" which exercised program code against a small set of ad hoc test cases.

As modeling efforts grew from rather small projects to more complex endeavors, validation complexities increased. Later, more rigorous validation techniques backed by statistical tests were developed. Today, validation is an important component of expert system research and development.

Many of the validation techniques currently employed by expert system modelers owe their origin to early simulation and conventional software developers.

Validation answers the question "is it the right system? The scope of the specifications is rarely precise, and it is practically impossible to test a system under all the rare events possible.

Therefore, it is impossible to have an absolute guarantee that a program satisfies its specification, only a degree of confidence that a program is valid can be obtained. That is, to what extent is the user satisfied with the technical details provided in the system? To what extent are the utilities provided useful? In order to perform the technical validation of the present expert system designed for the estimation of heating and cooling loads results obtained by the expert system are compared with results from two other methods.

The results obtained from an assignment given to the MAE class, students majoring in Mechanical engineering is considered. ASEAM models energy use in both commercial and residential buildings. The program simulates heating and cooling requirements, calculates the results of energy efficiency measures. Figure 6. Area of walls : sq. Window area : sq.

When the above data is input to the expert system, the output is obtained as shown in figure 6. Also, the outdoor design temperature in the assignment is F whereas it is 13 deg. F in the expert system. The Latent heat component in the infiltration appears to be a much higher contribution to the total heat load in the estimation. The cooling load value from the expert system differs from the values from the other two methods because the expert system considers the latent component of heat gain due to infiltration.

The outdoor temperature in this case is 95 deg. F whereas a value of F was used in the class. It can be concluded that the system developed gives output comparable to the results obtained by the ASEAM software and hand calculations. Table 6. The results obtained by the expert system are higher than the other two estimations because more detailed considerations have been made in the design of the expert system.

The Space heat and cooling loads estimated by the expert system are compared with the results obtained from the students of class who used the ASEAM software. The loads estimated by hand calculations are also given. From the validation it is learnt that the HVAC analysis done using the expert system has been robust enough to get appropriate results. It can be concluded that the expert system definitely proves to be an available, dependable and detailed technical tool to evaluate heat recovery and estimate the HVAC loads.

Turner, W. Goldstick , R. Thumann, A. Kennedy, W. Nagarajan, S. Pabba, R. Veena, R. Jacques, J. Chiogioji, M. Electric power research Institute. Kenney, W. Bagbey, D. Tulaca, A. Jordan C. Johnson, K. Culp, C.

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Therefore, effective strategies for the prediction and prevention of CVD toxicities are critically important. The latency and severity of radiotherapy cardiotoxicity, as well as accelerated atherosclerosis and cerebral vascular disease, is related to multiple factors, including the dose total per fraction , the volume of the heart irradiated, concomitant administration of other cardiotoxic drugs, and patient factors which include, amongst other factors, younger age, traditional risk factors, and history of heart disease.

Signs or symptoms of cardiac dysfunction should be monitored before and periodically during and after cancer treatment for early detection of abnormalities in patients receiving potentially cardiotoxic chemotherapy. Detection of subclinical abnormalities using imaging and measurement of circulating biomarkers such as cardiac troponins and natriuretic peptides is currently recommended.

Exercise should be strongly advised. Chronic obstructive pulmonary disease COPD is a complex, progressive respiratory disorder and currently the fourth leading cause of death worldwide. It is characterized by chronic airflow limitation with respiratory symptoms and is associated with an increased inflammatory response and abnormalities of the airways caused by significant exposure to noxious particles or gases mainly smoking.

Nevertheless, COPD patients have a two- to three- fold increased risk of CVD compared with age-matched controls when adjusted for tobacco smoking. The high prevalence of CVD in COPD patients may be explained by the fact that both diseases share common risk factors, such as smoking, ageing, hypertension, and dyslipidaemia.

Atherosclerosis and coronary artery calcification may be the result of oxidative stress, and reductions in antiaging molecules causing both lung and vascular ageing. Cardiac arrhythmias are common and may be due to the haemodynamic effects pulmonary hypertension, diastolic dysfunction, atrial structural, and electrical remodelling caused by the disease in combination with autonomic imbalance and abnormal ventricular repolarization.

Achieving adequate exercise is difficult, vasodilators for myocardial perfusion scanning may be contraindicated because of the risk of bronchospasm, and stress or transthoracic echocardiography is often disturbed by poor ultrasound windows. Computed tomography coronary angiography or magnetic resonance imaging may be alternatives, but remain expensive, time consuming, and not always available. The use of COPD medications i. Olodaterol may reduce the risk of overall CV adverse events and formoterol may decrease the risk of cardiac ischaemia.

Long-acting beta agonists may reduce the incidence of hypertension, but may also increase the risk of HF, so should be used with caution in HF patients. Inflammatory conditions increase CVD risk both acutely and over time.

In other chronic inflammatory conditions, such as psoriasis and ankylosing spondylitis, CVD risk may also be increased. However, the strength of the evidence is less strong, as is the independence of such increased risks from the classical ASCVD risk factors. Nonetheless, it seems prudent to at least consider CVD risk assessment in patients with any chronic inflammatory condition, and to take into account the presence of such conditions when there is doubt regarding initiation of preventive interventions.

The cumulative disease burden and recent degree of inflammation are important determinants of the risk-enhancing effect. Apart from optimal anti-inflammatory treatment, CVD risk in inflammatory conditions should be treated with similar interventions as in the general high-risk population, as there is evidence that traditional methods to lessen risk e.

CVD and influenza have long been associated, due to an overlap in the peak incidence of each disease during winter months. Epidemiological studies have noted an increase in CV deaths during influenza epidemics, indicating that CV complications of influenza infection, including acute ischaemic heart disease and, less often, stroke, are important contributors to morbidity and mortality during influenza infection.

The risk of AMI or stroke is more than four times higher after a respiratory tract infection, with the highest risk in the first 3 days after diagnosis. Studies have linked periodontal disease to both atherosclerosis and CVD, — and serological studies have linked elevated antibody titres of periodontal bacteria to atherosclerotic disease.

Available data indicate that migraine overall is associated with a two-fold increased risk of ischaemic stroke and a 1. Several lines of evidence also indicate that the vascular risk of subjects with migraine may be magnified by cigarette smoking and by the use of combined hormonal contraceptives.

Sleep disturbances or abnormal sleep durations are associated with increased CVD risk. In the general population, the prevalence of general sleep disturbances is around The most important sleep-related breathing disorder is OSA, which is characterized by repetitive episodes of apnoea, each exceeding 10 seconds. The precise mechanism by which mental disorders increase CVD remains uncertain.

The detrimental effects are potentially caused by unhealthy lifestyle, increased exposure to socioeconomic stressors, and cardiometabolic side-effects of some medications, but also by direct effects of the amygdala-based fear-defence system and other direct pathophysiological pathways. However, health inequalities and the prevalence of CV risk factors may be greater in these populations, although epidemiology research is scarce. Non-alcoholic fatty liver disease NAFLD has been associated with an increased risk of myocardial infarction and stroke.

A recent study investigating whether NAFLD increases CV risk beyond traditional risk factors shows that after adjusting for established risk factors, the associations did not persist. The rationale for screening these women for the occurrence of hypertension and DM is, however, quite strong. At present, no separate risk model for women with a history of hypertensive disorders of pregnancy seems necessary, despite their higher baseline risk.

The risk of developing DM is also elevated in these women RR 1. Erectile dysfunction ED , defined as the consistent inability to reach and maintain an erection satisfactory for sexual activity, has a multifactorial cause. ED and CVD share common risk factors hypercholesterolaemia, hypertension, insulin resistance and DM, smoking, obesity, metabolic syndrome, sedentary lifestyle, and depression and a common pathophysiological basis of aetiology and progression.

Medication used to prevent CVD, such as aldosterone receptor antagonists, some beta-blockers, and thiazide diuretics, can cause ED.

Clear communication about risks and benefits is crucial before any treatment is initiated. Risk communication is discussed in section 3. This applies not only to lifestyle measures, but also to drug interventions.

The reverse is also true: not only may some patients at very high risk forego interventions, some patients with low-to-moderate risk may be highly motivated to decrease their risk even further.

There is evidence that a higher proportion of women, compared to men, have a low awareness of their CVD risk and the need for therapeutic interventions. This warrants efforts to improve awareness, risk assessment, and treatment in women. Clinicians should provide a personalized presentation of guidelines to improve understanding, encourage lifestyle changes, and support adherence to drug therapy.

Applying this in daily practice faces different barriers. Communication strategies such as motivational interviewing are useful. Mobile phone applications may improve adherence to both medication and behavioural changes. In the subsequent sections, different domains of individual treatment are discussed.

Table 6 summarizes the treatment goals and some key interventions for different categories of patients. For additional information on risk categories and the principle of a stepwise approach to treatment targets, please refer to section 3. For details on treatment goals, how to achieve them, strengths of recommendations and levels of supporting evidence, please go to the relevant subsections.

Levels of evidence of intensified goals vary, see recommendation tables in sections 4. PA reduces the risk of many adverse health outcomes and risk factors in all ages and both sexes.

There is an inverse relationship between moderate-to-vigorous PA and all-cause mortality, CV morbidity and mortality, as well as incidence of type 2 DM. PA should be individually assessed and prescribed in terms of frequency, intensity, time duration , type, and progression.

Examples of aerobic PA include walking, jogging, cycling, etc. Practising PA should still be encouraged in individuals unable to meet the minimum. In sedentary individuals, a gradual increase in activity level is recommended.

When older adults or individuals with chronic conditions cannot achieve min of moderate-intensity PA a week, they should be as active as their abilities and conditions allow.

PA can be expressed in absolute or relative terms. A compendium of the energy cost in MET values for various activities is available. Less fit individuals generally require a higher level of effort than fitter people to perform the same activity. A relative intensity measure is necessary to provide an individualized PA prescription. Classification for both absolute and relative intensity and examples are presented in Table 7. Classification of physical activity intensity and examples of absolute and relative intensity levels.

Modified from Resistance exercise in addition to aerobic PA is associated with lower risks of total CV events and all-cause mortality. Sedentary time is associated with greater risk for several major chronic diseases and mortality. There is mixed evidence to suggest how activity bouts that interrupt sedentary behaviour are associated with health outcomes.

Although recommendations about nutrients and foods remain important for CV health, there is a growing concern about environmental sustainability, supporting a shift from an animal- to a more plant-based food pattern. Risk of CHD is reduced when dietary saturated fats are replaced appropriately Figure This is also the case when replacing meat and dairy foods.

Trans fatty acids, formed during industrial processing of fats, have unfavourable effects on total cholesterol increase and HDL-C decrease. When guidelines to lower saturated fat intake are followed, reductions in dietary cholesterol intake follow. A reduction in sodium intake may reduce SBP by, on average, 5. Salt reduction can be achieved by dietary choices fewer processed foods and the reformulation of foods by lowering their salt content see section 5.

Potassium e. However, intervention trials have failed to confirm these findings. Also, trials of supplementation with B vitamins B6, folic acid, and B12 , and vitamins C and D have not shown beneficial effects. From both a health and an environmental point of view, a lower consumption of meat, especially processed meat, is recommended. By reducing processed meats, salt intake will also be reduced. The World Cancer Research Fund recommends limiting red meat consumption to — g per week.

The upper safe limit of drinking alcoholic beverages is about g of pure alcohol per week. How this translates into number of drinks depends on portion size, the standards of which differ per country, mostly between 8 and 14 g per drink. This limit is similar for men and women. Results from epidemiological studies have suggested that, whereas higher alcohol consumption is roughly linearly associated with a higher risk of all stroke subtypes, coronary disease, HF, and several less common CVD subtypes, it appeared approximately log-linearly associated with a lower risk of myocardial infarction.

Regular consumption of sugar-sweetened beverages i. In the EPIC European Prospective Investigation into Cancer and Nutrition cohort, both artificially and sugar-sweetened soft drinks were associated with all-cause mortality, while only the former was associated with circulatory diseases. Moderate coffee consumption 3—4 cups per day is probably not harmful, perhaps even moderately beneficial.

No studies with clinical endpoints have been performed yet. Red yeast rice supplements are not recommended and may even cause side-effects. Studying the impact of a total dietary pattern shows the full preventive potential of diet. The Mediterranean diet includes high intakes of fruits, vegetables, pulses, wholegrain products, fish, and olive oil, moderate consumption of alcohol, and low consumption of red meat, dairy products, and saturated fatty acids.

Although diet, exercise, and behaviour modification are the main therapies for overweight and obesity, they are often unsuccessful in the long term. In this group, emphasis should be less on weight loss and more on maintaining muscle mass and good nutrition.

Energy restriction is the cornerstone of management. PA is essential to maintain weight loss and prevent rebound weight gain, but is not reviewed here. Hypocaloric diets may be categorized as:. Diets that aim to reduce ASCVD, including plant-based , and hypocaloric Mediterranean diets, , with modifications to suit local food availability and preferences.

Diets focusing on specific food groups e. Diets that restrict energy intake for specified time periods, for example on 2 days a week or alternate days intermittent fasting or during certain hours of the day time-restricted eating.

These diets give broadly similar short-term weight loss. The quality of nutrients in a diet, for example substituting unsaturated for saturated fats see section 4. Low or very low carbohydrate diets may have advantages regarding appetite control, lowering triglycerides, and reducing medications for type 2 DM. Studies beyond 2 years are scarce. Extreme carbohydrate intakes should be avoided in the long term and plant substitutions of fat and protein for carbohydrates are advantageous over animal ones.

Intermittent fasting diets produce equivalent weight loss to continuous energy restriction when matched for energy intake. A very effective treatment option for extreme obesity or obesity with comorbidities is bariatric surgery.

Recommendations for mental healthcare and psychosocial interventions at the individual level. Details explaining this recommendation are provided in the supplementary material section 2. Treatment of an unhealthy lifestyle will reduce CVD risk as well as improve mental health. Smoking cessation, for instance, has a positive effect on depression outcomes, , as do exercise therapy , and healthy dietary practices.

Several observational studies indicate that treatment or remission of depression reduces CVD risk. Concerning side-effects of psychopharmacological treatments, many psychiatric drugs are associated with an increased risk of sudden cardiac death. Stopping smoking is potentially the most effective of all preventive measures, with substantial reductions in repeat myocardial infarctions or death. Total health benefits will be even larger because of gain in non-CVD health. Quitting must be encouraged in all smokers, and passive smoking should be avoided as much as possible.

Very brief advice may be advantageous when time is limited Table 9. A major impetus for cessation occurs at the time of diagnosis or treatment of CVD. Prompting a person to try to quit, brief reiteration of CV and other benefits of quitting, and agreeing on a specific plan with a follow-up arrangement are evidence-based interventions. Smokers who quit may expect an average weight gain of 5 kg, but the health benefits of tobacco cessation outweigh risks from weight gain.

Drug support for stopping smoking should be considered in all smokers who are ready to undertake this action. Evidence-based drug interventions include nicotine-replacement therapy NRT , bupropion, varenicline, and cytisine not widely available. Combination vs. Varenicline 1 mg b. NRT was 1. Lower or variable doses are also effective and reduce side-effects. Varenicline beyond the week standard regimen is well tolerated.

Varenicline initiated in hospital following ACS is efficacious and safe. The main side-effect of varenicline is nausea, but this usually subsides.

A causal link between varenicline and neuropsychiatric adverse events is unlikely. Cytisine is effective for smoking cessation, but evidence to date is limited. Electronic cigarettes e-cigarettes simulate combustible cigarettes by heating nicotine and other chemicals into a vapour. E-cigarettes deliver nicotine without most of the tobacco chemicals, and are probably less harmful than tobacco. Recent evidence suggests that e-cigarettes are probably more effective than NRT in terms of smoking cessation.

Furthermore, as e-cigarettes are addictive, their use should be subject to similar marketing controls as standard cigarettes, especially the flavoured varieties that appeal to children. This section covers recommendations for the diagnosis and treatment of unfavourable blood lipid levels. Recent evidence has confirmed that the key initiating event in atherogenesis is the retention of LDL and other cholesterol-rich lipoproteins within the arterial wall.

Non-fasting sampling of lipid parameters is recommended for general risk screening, since it has the same prognostic value as fasting samples. It also has an advantage in that it is accurate in a non-fasting setting, and may be more accurate in patients with DM. There is evidence for a role of non-HDL-C as a treatment target as it captures the information regarding all apolipoprotein-B-containing lipoproteins.

Corresponding non-high-density lipoprotein cholesterol and apolipoprotein B levels for commonly used low-density lipoprotein cholesterol goals. Apolipoprotein B provides a direct estimate of the total concentration of atherogenic lipid particles, particularly in patients with elevated triglycerides. However, on average, the information conferred by apolipoprotein B is similar to that of calculated LDL-C.

Recommendation on low-density lipoprotein cholesterol goals a. Recommendation from section 3. LDL-C goals are summarized in the recommendations below.

Treatment should be a shared decision-making process between physicians and the patient. As explained earlier in these guidelines section 3.

This approach may seem novel but, in reality, resembles clinical practice, where treatment intensification is considered based on anticipated benefit, side-effects, and—importantly—patient preferences. In apparently healthy people, lifetime treatment benefit of LDL-C reduction may play a role in shared decision-making, together with risk modifiers, comorbidities, patient preference, and frailty. Figure 12 may support decision-making, as it shows the estimated lifetime benefits in years-free-of-CVD in relation to the total CVD risk profile, calibrated in low-to-moderate CVD risk countries.

Given that lower is better , we encourage liberal intensification of treatment, particularly if submaximal doses of low-cost generic statins are used and side-effects are not apparent.

Importantly, there are no differences in the RR reductions between men and women and between younger and older patients at least up to age 75 years , or between those with and without DM. PA and other lifestyle factors, rather than drug treatment, remain important means of increasing HDL-C levels. The presence of dyslipidaemias secondary to other conditions must be excluded before beginning treatment, as treatment of underlying disease may improve hyperlipidaemia without requiring lipid-lowering therapy.

This is particularly true for hypothyroidism. In addition, lifestyle optimization is crucial in all patients with higher than optimal lipid levels. Dietary factors influence the development of ASCVD, either directly or through their action on traditional risk factors, such as plasma lipids, BP, or glucose levels.

Consistent evidence from epidemiological studies indicates that higher consumption of fruit, non-starchy vegetables, nuts, legumes, fish, vegetable oils, yoghurt, and wholegrains, along with a lower intake of red and processed meats, foods higher in refined carbohydrates, and salt, is associated with a lower incidence of CV events.

The currently available lipid-lowering drugs include inhibitors of 3-hydroxymethylglutaryl-coenzyme A reductase statins , fibrates, bile acid sequestrants, selective cholesterol absorption inhibitors e. Bempedoic acid, an oral cholesterol synthesis inhibitor, has recently been approved in several countries. Usage is mainly intended in combination with ezetimibe in patients with statin intolerance. ASCVD outcome trials are not expected before the end of These results were obtained either on top of statin or without other lipid-lowering therapies, and with almost no side-effects.

Inclisiran has been approved in several European countries. The expected LDL-C reductions in response to therapy are shown in Figure 13 , and may vary widely among individuals. A stepwise approach to LDL-C targets is recommended; see section 3. Adapted from 3. Statins also lower triglycerides, and may reduce pancreatitis risk.

The most frequent adverse effect of statin therapy is myopathy, but this is rare. A meta-analysis ruled out any contribution to an increase in non-CV mortality. Increased levels of liver enzymes may occur during statin therapy, and are usually reversible.

Routine monitoring of liver enzyme values is not indicated. Rhabdomyolysis is extremely rare. As statins are prescribed on a long-term basis, possible interactions with other drugs deserve particular and continuous attention, as many patients will receive pharmacological therapy for concomitant conditions.

In practice, management of a patient with myalgia but without a major increase in creatine kinase is based on trial and error, and usually involves switching to a different statin or use of a very low dosage several days a week, with a gradual increase in frequency and dosage. A management algorithm may help to manage these patients. The combination of statin with ezetimibe brings a benefit that is in line with meta-analyses showing that LDL-C reduction has benefits independent of the approach used.

Their efficacy appears to be largely independent of background therapy. PCSK9 inhibitors are costly, and their cost-effectiveness, long-term safety, and effect in primary prevention are as yet unknown.

We recommend considering cost-effectiveness in a loco-regional context before implementing recommendations that involve their use. Recommendations for the treatment of hypertriglyceridaemia are shown in the Recommendations below. Fibrates are used primarily for triglyceride lowering and, occasionally, for increasing HDL-C. Evidence supporting the use of these drugs for CVD event reduction is limited, and given the strong evidence favouring statins, routine use of these drugs in CVD prevention is not recommended.

In patients with severe primary hypertriglyceridaemia, referral to a specialist must be considered. An evidence-based approach to the use of lipid-lowering nutraceuticals could improve the quality of the treatment, including therapy adherence, and achievement of the LDL-C goal in clinical practice.

However, it has to be clearly stressed that there are still no outcome studies proving that nutraceuticals can prevent CVD morbidity or mortality. Level of evidence. In addition, the relative effects of non-statin drugs that lower LDL-C ezetimibe and PCSK9 inhibitors, on top of high-intensity statin therapy are also similar in both women and men.

As a result, class and level of evidence have been modified in some age groups, in particular the category of patients between 70 and 75 years. Although a single age cut-off is now used, it is important to stress that all such age cut-offs are relatively arbitrary, and biological age influences this threshold in clinical practice.

General recommendations for lipid-lowering treatment in older patients are summarized below. Under the age of 70 years, statins are recommended for primary prevention depending on the level of risk. Above that age, initiation of statin treatment for primary prevention may be considered when at very high risk, but we explicitly recommend also taking other arguments into account, such as risk modifiers, frailty, estimated life-time benefit, comorbidities, and patient preferences see section 3.

In case of renal function impairment or risk for drug interactions, the statin dose should be up-titrated carefully. In terms of LDL-C targets, there is insufficient evidence to support targets for primary prevention in older patients. Frailty, polypharmacy, and muscle symptoms remain relevant factors to consider in older patients.

Similar to prevention in apparently healthy individuals, we propose a stepwise approach to lipid control, dependent on risk, estimated lifetime benefit, comorbidities, and patient preferences Figure 8.

See Table 4 for details. Flow chart of cardiovascular risk and risk factor treatment in patients with type 2 diabetes mellitus. See Box 1. The role of risk factors and comorbidities in atrial fibrillation. Estimated percentage change in risk of coronary heart disease associated with isocaloric substitutions of saturated fat for other types of fat or carbohydrates. Reproduced from Sacks et al. Lifetime atherosclerotic cardiovascular disease benefit from smoking cessation for apparently healthy persons, based on the following risk factors: age, sex, systolic blood pressure, and non-high-density lipoprotein-cholesterol.

The model is currently validated for low- and moderate-risk countries. If patients with CKD already on a hypolipidaemic therapy enter end-stage renal disease, the therapy may be maintained. Recommendations for lipid management in patients with moderate-to-severe chronic kidney disease Kidney Disease Outcomes Quality Initiative stages 3—5.

Besides genetic testing not always affordable , use of the Dutch Clinical Lipid Network criteria Table 11 is recommended to identify possible FH. Homozygous FH is rare and should always be placed under the care of lipid experts. Dutch Lipid Clinic Network diagnostic criteria for familial hypercholesterolaemia. Categories for conventionally measured seated office blood pressure a.

BP category is defined according to seated clinic BP and by the highest level of BP, whether systolic or diastolic. Isolated systolic hypertension is graded 1, 2, or 3 according to SBP values in the ranges indicated. See section 4. Hypertension is one of the most important preventable causes of premature morbidity and mortality.

This section covers recommendations for the diagnosis and treatment of hypertension to be applied in routine primary and secondary care. Definitions of hypertension according to office, ambulatory, and home blood pressure. Office BP should be measured in standardized conditions using validated auscultatory or semi automatic devices, as described in Table Repeated automated office BP readings may improve the reproducibility of BP measurement.

There is limited information on the prognostic value of unattended automated office BP measurements. ABPM is the average of repeated automated measurements of BP during the daytime, night-time, and over 24 h. Patient self-monitoring may have a beneficial effect on medication adherence and BP control. Clinical indications for ambulatory or home monitoring are shown in Table Indications for home blood pressure monitoring or ambulatory blood pressure monitoring.

Assessment of nocturnal BP values and dipping status e. Ideally, all adults should be screened for the presence of hypertension, , but most countries lack the required resources and infrastructure. Formally, these guidelines recommend opportunistic screening at least in susceptible individuals, such as those who are overweight or have a family history of hypertension see section 3.

Expected low-density lipoprotein cholesterol reductions for combination therapies. Adapted from Mach et al. Screening and diagnosis of hypertension. The risk associated with white-coat hypertensionis lower than sustained hypertension but may be higher than normotension. People with white-coat hypertensionshould receive lifestyle advice to reduce their CV risk and be offered BP measurement at least every 2 years by ABPM or HBPM because of high rates of transition to sustained hypertension.

Routine drug treatment for white-coat hypertensionis not indicated. It is more common in younger people and in those with high-normal office BP. The routine work-up for hypertensive patients is shown in Table Alongside clinical examination, this is designed to:. Consider potential secondary causes of hypertension, e. Also, carefully evaluate substance abuse e. More detail on work-up of suspected secondary hypertension is provided elsewhere.

Patient characteristics that should raise the suspicion of secondary hypertension. Adapted from 4. Echocardiography is recommended in patients with ECG abnormalities, and should be considered when the result will influence clinical decision-making. Fundoscopy is recommended in grade 2 or 3 hypertension and in all patients with DM. The routine measurement of other biomarkers and use of vascular imaging are not recommended. The treatment of hypertension involves lifestyle interventions for all patients and drug therapy for most patients.

Lifestyle interventions are indicated for all patients with high-normal BP or hypertension because they can delay the need for drug treatment or complement the BP-lowering effect of drug treatment. Moreover, most lifestyle interventions have health benefits beyond their effect on BP.

Lifestyle is discussed extensively in section 4. Drug treatment decisions in CVD prevention are mostly based on absolute CVD risk, risk modifiers, comorbidities, estimated benefit of treatment, frailty, and patient preferences. The same is true for hypertension.

In younger patients, however, the absolute year CVD risk is often low, and lifetime benefit of treatment should be considered and communicated before instituting treatment Figure 6 and section 3. In many such cases, the absolute lifetime benefit per mmHg reduction in SBP is at least moderate to high [ Figure 15 lifetime benefit calibrated in low-to-moderate CVD risk countries].

Also, the presence of HMOD mandates treatment of grade 1 hypertension. Lifetime benefit from lowering systolic blood pressure by 10 mmHg for apparently healthy persons, based on the following risk factors: age, sex, current smoking, systolic blood pressure, non-high-density lipoprotein cholesterol.

For 20 mmHg SBP lowering, the average effect is almost twice as large, etc. When drug treatment is used, the aim is to control BP to target within 3 months. Evidence now suggests that the BP targets in the previous iteration of this guideline 2 were too conservative, especially for older patients.

In line with the stepwise approach section 3. Also, in these older and especially frail patients, it may be difficult to achieve the recommended target BP range due to poor tolerability or adverse effects, and high-quality measurement and monitoring for tolerability and adverse effects is especially important in these groups.

Although a single age cut-off is provided, it is important to stress that biological age influences this threshold in clinical practice.

BP targets for patient subgroups with various comorbidities are shown in Table Recommended office blood pressure target ranges. The subsequent optimal goals are listed below. The most important driver of benefit is the magnitude of BP lowering. Single-drug therapy will rarely achieve optimal BP control. Initial therapy with a combination of two drugs should be considered usual care for hypertension.

Initial combination therapy, even low-dose combination therapy, is more effective at lowering BP than monotherapy, , , and will reduce BP faster and reduce heterogeneity in response. Single-pill strategy to treat hypertension: poor adherence to BP-lowering medication is a major cause of poor BP control rates, and is directly related to the number of pills.

This strategy will control BP in most patients. Recommended drug therapy and treatment algorithm: five major classes of BP-lowering drug therapy have shown benefit in reducing CV events; angiotensin-converting enzyme ACE inhibitors, angiotensin receptor blockers ARBs , beta-blockers, calcium channel blockers CCBs , and thiazide or thiazide-like diuretics.

Core drug treatment strategy for hypertension. This algorithm is appropriate for most patients with hypertension-mediated organ damage, diabetes mellitus, cerebrovascular disease, and peripheral artery disease.

Resistant hypertension is defined as BP being uncontrolled despite treatment with optimal or best-tolerated doses of three or more drugs including a diuretic, and confirmed by ABPM or HBPM. The diagnosis and treatment of hypertension in women is similar to that in men, except for women of child-bearing potential or during pregnancy, because of potential adverse effects of some drugs on the foetus, especially in the first trimester.

In addition, the effect of oral contraceptive pills on the risk of developing or worsening hypertension should be considered. Treatment of hypertension is usually maintained indefinitely because cessation of treatment usually results in a return of BP to pretreatment levels. In some patients with successful lifestyle changes, it may be possible to gradually reduce the dose or number of drugs. After BP is stable and controlled, visits should be scheduled at least annually, and include the control of other risk factors, renal function, and HMOD, as well as reinforce lifestyle advice.

When there is a loss of BP control in a previously well-controlled patient, non-compliance with therapy should be considered. Supervision of patient follow-up increasingly involves nurses and pharmacists and is likely to become increasingly supported by telemedicine and app-based technologies. This has led to newer treatment algorithms. Most persons with DM are obese, so weight control is crucial.

Several dietary patterns can be adopted, where the predominance of fruits, vegetables, wholegrain cereals, and low-fat protein sources is more important than the precise proportions of total energy provided by the major macronutrients. Salt intake should be restricted. Specific recommendations include limiting saturated and trans fats and alcohol intake, monitoring carbohydrate consumption, and increasing dietary fibre.

A Mediterranean-type diet, where fat sources are derived primarily from monounsaturated oils, is protective against ASCVD. More detail is provided in section 4. A combination of aerobic and resistance exercise training is effective in preventing the progression of type 2 DM and for the control of glycaemia. Smokers should be offered cessation support see section 4. Lifestyle intervention lowers future microvascular and macrovascular risks as well as mortality in the longer term.

The UKPDS established the importance of intensive glucose lowering with respect to CVD risk reduction in persons newly diagnosed with DM, with better evidence to support metformin, which correctly remains the first agent of choice for the majority of patients diagnosed with DM. Three trials were conducted to see if CV events could be reduced further with more intensive glycaemia treatment.

Subsequent meta-analyses of relevant trials showed reductions in non-fatal AMI and CAD events, but no effect on stroke or total mortality. HbA1c targets should be personalized to individual characteristics and preferences.

Four trials of dipeptidyl peptidase-4 inhibitors — in patients with DM and existing ASCVD or at high risk demonstrated non-inferiority i. The specific pattern of trial results e. One trial showed an excess of amputations and fractures, but none of the other trials noted imbalances.

Patients should be advised on the importance of genitourinary hygiene before being prescribed these medications. The results cannot be explained by lowering of glucose levels and, in multiple SGLT2 inhibitor and GLP-1RA trials, subgroup analyses suggested that these benefits could be independent of metformin use.

Risks of hypoglycaemia can be reduced by lowering doses of sulphonylureas or insulin. The panel concluded that this approach should be initiated independent of background therapy, glycaemic control, or individualized treatment goals. A risk score plus cost-effective analyses would be useful to determine which patients free from ASCVD or evidence of TOD may be recommended for these newer drugs.

In all the above, there is no evidence of any sex interaction in benefits. Finally, people with type 2 DM should be involved in decision-making after explanation of the potential benefits and side-effects of the drugs. The DCCT Diabetes Control and Complications Trial established the importance of tight glucose control to lessen the risks of both microvascular and macrovascular disease in both men and women with type 1 DM.

SGLT2 inhibitors improve metabolic control in type 1 DM and may complement insulin therapy in selected patients. Bleeding risks were particularly increased in older persons. Other recent meta-analyses found very similar results. Wider use than this could potentially amplify the benefit of aspirin in primary prevention for patients at higher atherosclerotic risk.

Until then, decisions in these high-risk persons should be made on a case-by-case basis, taking both ischaemic risk and bleeding risk into consideration. In patients with previous myocardial infarction, stroke, or LEAD, clopidogrel showed a slight superiority for ischaemic events with respect to aspirin, with a similar safety profile.

A meta-analysis showed a clinically modest risk reduction with P2Y 12 inhibitor monotherapy number needed to treat: , and no effect on all-cause or vascular mortality and major bleeding. Proton pump inhibitors reduce the risk of gastrointestinal bleeding in patients treated with antiplatelet drugs and may be a useful adjunctive therapy to improve safety. Although this interaction has not been shown to affect the risk of ischaemic events, coadministration of omeprazole or esomeprazole with clopidogrel is not recommended.

Acknowledging that the process of atherosclerosis has inflammatory components has led to the investigation of various anti-inflammatory therapies in recent years. The first study to examine the effects of reducing inflammation without impacting lipid levels was CANTOS Canakinumab Antiinflammatory Thrombosis Outcome Study , in which the monoclonal antibody, canakinumab, provided proof-of-concept for anti-inflammatory therapy in high-risk patients.

Methotrexate was the second anti-inflammatory drug studied for this purpose, but was not proven effective in reducing CVD outcomes. The use of colchicine in daily practice remains to be established based on further clinical study data and experiences in daily practice. Nonetheless, the encouraging results justify consideration of low-dose colchicine in selected, high-risk patients.

Clinical trials and registries are highly heterogeneous, which influences national guidelines, legislation, and reimbursement. CR is a comprehensive multidisciplinary intervention , , , CR is supervised and carried out by adequately trained health professionals, including cardiologists CR starts as soon as possible after the initial CV event EBCR includes aerobic and muscular resistance exercise, which should be individually prescribed based on pre-exercise screening and exercise testing The number of EBCR sessions needs to exceed 36 During CR, all individually recognized CV risk factors need to be addressed and treated.

Although exercise training prescription should adopt the FITT frequency, intensity, time duration, and type of exercise model, inter-clinician variance and disagreement exists. Despite proven benefits, rates of referral, participation, and implementation are low.

Also, mobile device-based healthcare mHealth delivery through smartphones may be as effective as traditional centre-based CR, showing significant improvements in health-related quality of life.

Level of evidence applies less well to policy interventions, and the type of empirical evidence varies widely across the separate approaches suggested. Population level approaches to CVD prevention centre around upstream measures requiring broad public-health interventions targeting lifestyle and promoting monitoring of CVD. These measures are designed to address populations and are intended to shift the population attributable risk.

This is based on a prevention paradox described by Geoffrey Rose in If the prevalence of a significant RR factor is low, then the population attributable risk may be modest. Conversely, if a low-impact RR factor is common, the population attributable risk may be high. This prevention approach following the Geoffrey Rose paradigm , states that small shifts in the risk of disease across a whole population consistently lead to greater reductions in disease burden than does a large shift in high-risk individuals only.

This population-wide approach—as opposed to strategies targeting high-risk individuals—has major advantages at the population level whilst sometimes having only a modest benefit at the individual level, because it addresses the CV health of a large number of individuals over the entire life course.

It should be noted that high-risk and population-level prevention strategies are not mutually exclusive and must therefore coexist. Prevalence of high-risk conditions and incidence rates of CVD vary across countries. Many of their underlying causes are known, and they are closely related to dietary habits, PA, smoking, alcohol, employment, social deprivation, and the environment.

The objective of population approaches to prevention of CVD is to control the underlying determinants of CV health and, in this way, reduce population incidence rates. The population approach may bring numerous benefits, such as narrowing the gap in health inequalities, preventing other conditions such as cancer, pulmonary diseases, and type 2 DM, and saving costs from the avoided CV events and early retirement due to health problems. Individual behaviour is enacted in an environment with hierarchical levels, which encompass individual choice, family influence, cultural and ethnic grouping, workplace, healthcare, and policy at the regional, state and global levels e.

EU policies and international trade agreements. The aim of this section of the guidelines is to provide evidence-based suggestions for the most effective interventions to reduce CVD risk at the population level, improve CVD health, and promote healthy choices at the community, regional, and global level. Health challenges cannot be solved by the healthcare systems alone and require political support.

Population-level interventions aim to alter the societal environment, modify certain social determinants of health, and provide incentives to encourage changes in individual behaviour and exposure to risk factors.

Social determinants of health include socioeconomic status education, occupation, and income , wealth inequalities, neighbourhood and urban design, and social networks, to name but a few. Healthcare professionals play an important role in advocating evidence-based population-level interventions. By modifying the general context, one can induce healthy decisions as a default in entire populations all age groups and particularly vulnerable ones. The task for both national and local authorities is to create social environments that provide healthier defaults, taking health literacy into account.

While interpreting this section, it is important to recognize that there are often vested interests, which may influence policy decisions on health promotion. The supplementary material for this section presents evidence for population-level strategies dealing with specific risk factor interventions for PA section 5.

Lifestyle changes at the population level take time, may be expensive, and need to be sustained over time. Furthermore, the benefits may be slow to manifest; however, they persist over the long term and improve health-related quality of life and well-being.

Please see the supplementary material section 3. Air pollution contributes to mortality and morbidity. It specifically increases the risk of respiratory and CV diseases, notably CAD, HF, cardiac arrhythmias and arrest, cerebrovascular disease, and venous thromboembolism.

Important sources of fine particles are road traffic, power plants, and industrial and residential heating using oil, coal, and wood. Main components of outdoor air pollution include airborne PM ranging in size from coarse particles 2. The EU Commission released a policy package to be implemented by , with measures to reduce harmful emissions from traffic, energy plants, and agriculture.

Indoor air pollution and exposure to noise must also be highlighted. Household air pollution, such as that produced from burning biomass, accounts for over 3 million deaths worldwide. It should be noted that mitigating efforts to reduce noise exposure have not, as yet, proven to have a beneficial health effect. The extent to which environmental exposures in soil and water contribute to CVD has also been established. Patient organizations and health professionals have an important role in supporting education and policy initiatives.

Economic incentives, such as reduced taxes on electric and hybrid cars, can contribute to the improvement of air quality as well as incentives encouraging the use of public transport.

Urban design promoting the construction of new houses and schools in areas remote from highways and polluting industries needs to be urged. An example of such legislation is the European Green Deal, by which the EU aims to be climate neutral by Societal measures to reduce such fuels, and transfer towards renewable sources, are becoming urgent to reduce air pollution and climate change.

This section addresses CVD prevention in specific clinical contexts. A significant number of patients already have such comorbidities, which put them at additional risk. The general principles of lifestyle modification and treatment of major risk factors are outlined in section 4.

In this section, only disease-specific aspects are added. Disease-specific acute management of coronary syndromes is covered in detail in recent guidelines. As for antithrombotic therapy, dual antiplatelet therapy DAPT for 12 months, preferably with prasugrel or ticagrelor, is the standard antithrombotic treatment after ACS. Based on the above, and in line with the CCS Guidelines, adding a second antithrombotic drug P2Y 12 inhibitor or low-dose rivaroxaban to aspirin for long-term secondary prevention should be considered for patients who are at high ischaemic risk and do not have a high risk of bleeding.

It may also be considered in patients who are at moderate ischaemic risk and without a high risk of bleeding, but the benefits are lower. The management of dyslipidaemia and hypertension in patients with CAD is discussed in sections 4. The management of HF aims to improve mortality, hospitalization rate, and quality of life. Regarding the management of CVD risk factors, similar basic rules apply for those with and without HF. However, in HF, low cholesterol levels , and low body weight are associated with increased mortality.

Conversely, regular exercise training particularly combined aerobic and resistance exercises improves clinical status in all patients with HF , , and improves CVD burden and prognosis in HFrEF. It is recommended to screen all patients with HF for both CV and non-CV comorbidities; if present, they should be treated. Recently, an oral soluble guanylate cyclase receptor stimulator vericiguat , administered along with standard neurohormonal blockade in symptomatic patients with HFrEF with recent HF hospitalization, reduced the composite of death from any cause or HF hospitalization.

Other drugs bring additional moderate benefits for selected patients with symptomatic HFrEF. Diuretics, , ivabradine, , and hydralazine , should be considered, and digoxin may be considered as complementary therapies in specific patients with symptomatic HFrEF.

Some of these therapies reduce CV morbidity and mortality e. Additionally, for selected patients with symptomatic HFrEF, there are indications for an implantable cardioverter defibrillator to reduce the risk of sudden death and all-cause mortality, and for cardiac resynchronization therapy to reduce morbidity and mortality for details, see HF Guidelines.

For implantable cardioverter-defibrillator and cardiac resynchronization recommendations, see Interventions for cerebrovascular diseases depend on the type of event, i. In patients with ischaemic stroke or TIA, antithrombotics prevent further vascular events. Cardioembolic ischaemia, which occurs mainly in AF, requires anticoagulation see sections 3.

In non-cardioembolic ischaemic stroke, aspirin is the most studied antithrombotic drug. However, DAPT with ticagrelor and aspirin did not improve the incidence of disability and contributed to severe bleeding.

In patients with non-cardioembolic ischaemic stroke, oral vitamin K antagonists are not superior to aspirin and carry a higher bleeding risk. Recommendations for BP and lipid management are congruent to the general recommendations outlined in sections 4. Comorbidities may guide the choice of antihypertensive agent.

Evidence of cerebrovascular lesions e. Silent cerebrovascular disease is a marker of increased risk of stroke. There are no studies addressing the best treatment options for silent cerebral ischaemia. All LEAD patients require lifestyle improvement and pharmacological therapy.

Smoking cessation increases walking distance and lowers amputation risk. Platelet inhibitors are used to prevent limb-related and general CV events. The optimal antiplatelet strategy remains unclear. Recommendations for patients with lower extremity artery disease: best medical therapy. Sign In. ESC Publications. Advanced Search. Search Menu. Article Navigation. Close mobile search navigation Article Navigation. Volume Article Contents Table of Contents. Abbreviations and acronyms.

Risk factors and clinical conditions. Risk factors and interventions at the individual level. Policy interventions at the population level. Risk management of disease-specific cardiovascular disease. Key messages. Typically those killed were aged between 20 and 29 and the biggest losses seen in and Of those killed, were male and three were female. The first three British casualties were non-hostile deaths in Kabul , from suicide, accidental weapons discharge and homicide. During , Private Darren John George , aged 23, from the Royal Anglian Regiment, was killed by a ricocheting bullet fired by a comrade who had a dizzy spell.

Despite orders rationing beer to just two small cans a day to help prevent such events occurring, Corporal Gregory became involved in a drunken fight with Sergeant Busuttil at a barbecue. Gregory then left the barbecue and returned with a loaded SA80 rifle and killed Busuttil, firing the rifle at him 'up to ten times'.

Gregory then committed suicide with the weapon. The Army was subsequently criticised by Wiltshire coroner David Masters when he recorded verdicts of unlawful killing on the death of Sergeant Busuttil and suicide on Corporal Gregory.

The British troops were in armoured [LTV] vehicles when a taxi swerved into their convoy and a bomber detonated Ibs of explosives. As a result of its Northerly situation it is unlikely that the Taliban were involved. The gunman attacked the soft-skinned 4x4 vehicle that the soldiers were travelling in, the vehicle was situated just a few hundred yards from the famous blue mosque. The gunman was arrested straight after the incident and has since been charged and jailed for the murder of LCpl Sherwood.

On 11 June, Captain Jim Philippson , aged 29, from 7 Parachute Regiment, Royal Horse Artillery, was killed in a gunbattle with suspected Taliban militants while he participated in a mobile patrol. Having been forced to abandon their "Snatch" Land Rover after it was struck by an RPG they were then engaged in a fierce firefight with Taliban forces during which both men were killed. The soldiers were taking part in an operation to detain a number of leading Taliban figures within the Sangin Valley.

The three died, and a number of others were wounded when a Type 63 mm Rocket hit the government compound they were defending in the town of Sangin. During July, Private Damien Raymond Jackson , aged 19, from 3rd Battalion, the Parachute Regiment, died as a result of injuries sustained during a firefight with Taliban forces at approximately hours local time in Sangin, central Helmand Province.

The incident occurred during a security patrol to clear a Helicopter landing site. Troops came under "substantial fire" from Taliban during the operation, which involved British troops, which was their largest action against the Taliban and the operation was supported by Afghan forces.

Lance Corporal Sean Tansey , aged 26, of the Household Cavalry Regiment, died as he repaired a damaged Scimitar tank at a military base in Helmand province on 12 August. He had been in the Army for 10 years serving in Yugoslavia, Sierra Leone, Macedonia, Afghanistan and Iraq and was about to be promoted to platoon sergeant when he died.

Lance Corporal Jonathan Hetherington of 14 Signal Regiment was shot dead while fighting rebels during an assault on his platoon house in Musa Qaleh in northern Helmand province on 27 August. RAF Nimrod crash. Fourteen British servicemen were killed when their Nimrod surveillance aircraft crashed following an on-board fire. The fire was caused when a fuel transfer pipe inside the aircraft ruptured during in-flight refuelling. Corporal Mark William Wright , aged 27, from Edinburgh, of the Parachute Regiment, died after a patrol entered an unmarked minefield in Helmand province.

Cpl Wright died attempting to save the life of an injured paratrooper. He was wounded during a Taliban attack on his base at Musa Quala, in Helmand province. He had been receiving specialist medical care since the attack and his parents were with him when he died.

The fighting took place in Sangin, Helmand province. Marine Gary Wright , aged 22, serving with Reconnaissance Troop, 45 Commando Royal Marines, was killed along with two children on 19 October when a suicide bomber on foot detonated explosives next to the Snatch Land Rover in which Wright was travelling; one other Royal Marine was seriously injured.

Marine Wigleys' death is believed to be the result of friendly fire which occurred when air support for ground troops was called to within a range termed "Danger close". He was killed when the vehicle he was driving struck an anti-tank mine while on a patrol in southern Helmand.

Marine Thomas Curry , aged 21, died on Saturday 13 January when elements of 42 Commando Royal Marines were engaged in a deliberate offensive operation near Kajaki, in Northern Helmand, Afghanistan. The Royal Marines Commandos were engaged in close-quarter fighting with the Taliban, and it was during this action that Marine Curry was killed. He died instantly as a result of enemy small arms fire.

Lance Corporal Ford died when elements of 45 Commando Royal Marines were engaged in a deliberate offensive operation to the south of Garmsir in southern Helmand, Afghanistan. The Royal Marine Commandos were attacking a major Taliban fort, and during the initial breach of the compound Lance Corporal Ford was shot and killed instantly. Marine Jonathan Holland , aged 23, from 45 Commando was killed by an anti-personnel mine during a routine patrol in the Sangin District of Helmand province on 21 February Marine Scott Summers , age 23, of 42 Commando Royal Marines died on Wednesday 21 February as a result of injuries sustained in a road traffic accident earlier that month in Afghanistan.

After initial treatment, Marine Summers was transported back to a specialist unit in the UK where he later died. Lead elements of the patrol were pinned down by enemy fire and Private Gray's Platoon manoeuvred to support their comrades and out-flank the enemy. As they manoeuvred, Private Gray's section engaged a group of armed Taliban fighters at a range of just 15 metres. A fierce firefight ensued, during which a small number of Taliban were killed.

During the battle Pte Gray was shot and despite receiving medical aid, he was pronounced dead on arrival at the British Hospital at Camp Bastion. Corporal Mike Gilyeat, aged 28, from the Royal Military Police, died on Wednesday 30 May when the American Chinook helicopter he was travelling in was shot down in the Kajaki area of northern Helmand.

Corporal Bonner was the lead Signaller serving with A Norfolk Company Group, 1 Royal Anglian Battlegroup, and had been travelling in a convoy roughly 11 km east of Hyderabad in the Gereshk region of Helmand Province when an explosion hit his vehicle. Guardsman Daniel Probyn, aged 22, from Tipton, 1st Battalion the Grenadier Guards died on Saturday 26 May following an explosion during an offensive operation to clear a Taliban stronghold on the outskirts of the town of Garmsir, in Southern Helmand.

Lance Corporal George Russell Davey, aged 23, from Suffolk, was killed on Sunday 20 May as a result of injuries sustained in a tragic firearms accident at the British base in Sangin, Afghanistan.

Guardsman Simon Davison, was killed by small arms fire while manning a checkpoint near the town of Garmsir in Helmand Province on Thursday 3 May Guardsman Davison was aged 22 and from Newcastle upon Tyne. Captain Dolan, and the forces that he was attached to, were observing a substantial force of Taliban fighters from the edge of a vantage point, when they came under fire from Taliban mortars. The first mortar round fatally wounded Captain Dolan and seriously injured a US soldier [58]. The patrol was conducting routine operations with the Afghan National Army when it was struck by an improvised explosive device.

Although all the injured soldiers were quickly extracted by helicopter to the ISAF medical facility at Camp Bastion, Sergeant Wilkinson was pronounced dead on arrival. Four other members of the patrol were injured. Gdn Hickey was part of a fire team providing covering fire as others in his platoon assaulted a Taliban position. During the enemy contact he suffered a gunshot wound. Gdn Hickey was rapidly evacuated by helicopter but was pronounced dead on arrival at the field hospital. Sergeant Barry Keen of 14 Signal Regiment was killed by a mm rocket when it hit the compound near Hydarabad in southern Afghanistan on Friday 27 July At a little after midnight on the morning of 30 August local time SAC Bridge was in a vehicle that was conducting a routine security patrol around Kandahar Airfield when it was caught in an explosion.

During a fighting patrol north west of Kajaki, in northern Helmand Province, southern Afghanistan, 7 platoon came under determined and accurate fire from the Taliban. A fierce firefight ensued and air support was requested and was supplied by two USAF F15E Aircraft, one of which dropped a bomb short of the intended target area killing the three soldiers.

At hours local time the patrol base came under attack from small arms fire, rocket-propelled grenades, and indirect fire. It was during this engagement that Captain Hicks was injured by shrapnel, but he refused medical treatment and morphine so that he could continue to lead his besieged troops against the Taliban.

An emergency response helicopter later took him to the medical facility at Camp Bastion for treatment, but he did not survive his injuries. Pte Rawson was part of a fighting patrol which came under heavy fire from Taliban fighters shortly before hours local time.

He was pronounced dead at the scene of the firefight. Wednesday 5 September The soldiers, both from the 2nd Battalion The Mercian Regiment Worcesters and Foresters , were taking part in a routine reassurance patrol 17 km north of Lashkar Gah when, shortly after hours local time, the Land Rover vehicle they were travelling in was caught in an explosion.

They were both pronounced dead at the scene. Another soldier and an interpreter were injured in the explosion [1]. They were taking part in a pre-planned operation to disrupt Taliban activity, south of Garmsir, southern Helmand Province, when their patrol was attacked by enemy fighters [2].

A number of other soldiers were also injured in the incident, two seriously. He was 29 years old. Corporal Violino was commanding an FL12 Self-Loading Dump Truck on a routine logistics convoy, moving vital engineering equipment to a Forward Operating Base 19 km north east of the town of Gereshk in Helmand province, when his vehicle was caught in an explosion [3].

They were travelling in a Pinzgauer High Mobility All-Terrain Vehicle , 5 km south west of their patrol base in an area north of Gereshk, on their way to a rendezvous point as part of a two vehicle replenishment patrol. The vehicle over-turned and landed on its roof in an irrigation channel. One other passenger was able to escape without injury [4]. Lance Corporal Jake Alderton, aged 22, from Bexley, of 36 Engineer Regiment died in southern Afghanistan on Friday 9 November the vehicle he was travelling in left the road and rolled off a bridge [6].

On Wednesday 14 November in southern Afghanistan Captain McDermid, who was serving with 2nd Battalion The Yorkshire Regiment, was leading a joint UK and Afghan National Army patrol to the south of the district centre of Sangin in Helmand Province, during which he was also mentoring an Afghan National Army officer in the leadership and infantry skills that platoon commanders need.

At approximately hours local time an Improvised Explosive Device detonated, which resulted in the death of Captain McDermid and serious injury to the Afghan interpreter who was accompanying him. On Saturday 8 December , in southern Afghanistan. Shortly before hours local time Sergeant Johnson was taking part in operations to recapture the town of Musa Qaleh in Helmand Province in what has become known as the Battle of Musa Qala when an explosive device detonated—suspected to be a mine—resulting in the death of Sergeant Johnson and inflicting serious injuries to another soldier in the same Pinzgauer Vector.

At just before hrs local time the soldiers were on a tactical patrol escorting two light guns and the ammunition for these guns, in support of the forthcoming attack on Musa Qala, to the north of Sangin, Helmand Province, when the vehicle they were travelling in was caught in an explosion.

Two other soldiers were also injured as a result of the blast, one had his back broken. At the inquest of Trooper Sadler it was ascertained that the two guns could have been flown in by helicopter. Shortly after hours local time the vehicle he was travelling in was hit by a roadside mine strike.

Corporal Gardiner was evacuated by helicopter to the field hospital at Camp Bastion for medical treatment but did not survive. Five other soldiers were injured in the explosion. Shortly before hours local time Corporal Lawrence was taking part in a joint UK—Afghan National Army night patrol in Kajaki, tasked with clearing a number of compounds. Immediately upon entry into a compound an explosive device detonated fatally injuring Corporal Lawrence.

Another soldier was also wounded, but his injuries were not life-threatening. The marines of Alpha Company were conducting a clearance patrol to deter Taliban intimidation of local Afghans.

It was during this action that an Improvised Explosive Device was detonated, which killed Corporal Mulvihill instantly. Just after hours local time on Sunday 30 March , the Marines were conducting a patrol in the vicinity of Kajaki, Helmand province, when the vehicle they were travelling in was caught in an explosion. Medical treatment was provided prior to both being evacuated to the field hospital at Camp Bastion. Despite the best efforts of the medical team, both died as a result of their wounds.

Consensus on the airfield was that the enemy had laid the IED behind the outgoing patrol, and the vehicle returned to the perimeter along the same route, triggering the explosion. Senior Aircraftman Thompson is the oldest British serviceman to have died in Afghanistan. At approximately hrs local time on Monday 21 April Trooper Pearson was part of the Armoured Support Company Royal Marines who were providing security to a resupply convoy that was returning to Camp Bastion when the vehicle he was driving hit a suspected mine.

Another soldier was injured in the blast and received medical treatment. Trooper Ratu Babakobau , aged 29, of the Household Cavalry Regiment was killed Friday 2 May in Helmand, Afghanistan at hrs local time while providing protection for a routine patrol in the Nowzad area of northern Helmand. The vehicle he was travelling in suffered a minestrike. Three other British soldiers and one local national were also injured in the incident.

The soldier was patrolling on foot in Musa Qala, Helmand, when he was caught in an explosion and died. No one else was injured. His troop were returning to their Forward Operating Base, when the BvS 10 Viking he was driving struck a suspected mine. Another two Royal Marines were also injured in the blast and received medical treatment. At approximately hours local time, the soldiers were on a routine foot patrol 1 km west of their Forward Operating Base in the Upper Sangin Valley when their patrol suffered a suicide explosive device.

During the exchange of fire Lance Corporal James Bateman and Private Jeff Doherty were killed in the face of the enemy amongst their colleagues and friends. One other soldier received wounds which required medical attention. All four soldiers were killed while taking part in a deliberate operation east of Lashkar Gah when the Snatch Land Rover in which they were travelling was caught in an explosion.

Another soldier was wounded in the incident and received treatment for his wounds at the UK Field Hospital at Camp Bastion. Private Whittaker was part of a mine detection team and was killed helping to ensure that large vehicle resupply convoys could reach Forward Operating Bases. LCpl Johnson was part of a vehicle checkpoint patrol operating in the Lashkar Gar area, when he was killed by an anti-personnel mine.

The incident occurred at hrs local time. Corporal Barnes was driving a Vector ambulance vehicle when it hit a suspected Improvised Explosive Device. He was returning to base after he had successfully aided in the helicopter evacuation of a casualty who had been injured earlier near Kajaki in northern Helmand. Five other soldiers were injured by small arms fire. His explosives sniffer dog, Sasha, was also killed in the incident.

The patrol received reports from locals that the Taliban were in the area but before they could take up defensive positions they received incoming fire, and the soldier sustained a single gunshot wound. At hrs local time, a routine patrol conducting reassurance and interdiction activities left Forward Operating Base FOB Gibraltar and at hrs local time encountered enemy forces and engaged them.

A short while later the patrol reported one casualty from the engagement who was seriously wounded by a blast, the soldier died shortly afterwards. Signaller Wayne Bland , aged 21 from Leeds, serving with 16 Signal Regiment was killed in a suicide attack on a vehicle patrol in Kabul, Afghanistan, 11 August At During that time an improvised explosive device was detonated which resulted in the death of Cpl Dempsey and shrapnel and blast injuries to one other ISAF soldier, an Afghan National Army soldier and the patrol interpreter.

The explosion is believed to have been from an improvised explosive device. The soldier was given first aid at the scene, but died a short time later [82]. As a consequence of this there was an explosion and WO2 O'Donnell died shortly afterwards from the injuries he sustained in the explosion.

The patrol was clearing an area essential for the security of the Kajaki hydroelectric dam when LCpl Mason was struck by an improvised explosive device. Tpr Munday was driving a Jackal MWMIK wheeled reconnaissance vehicle on a routine patrol approximately 23 km north of Forward Operating Base Delhi in Helmand province, Afghanistan when it detonated a contact triggered explosive device. Two other soldiers were also injured.

Rifleman Rai received a gunshot wound from enemy fire. Despite having received medical treatment at the scene he died a short time later from his wounds.

They were taking part in a patrol with soldiers from the Afghan Security Forces when their Jackal MWMIK vehicle was destroyed by an explosive device, both men were pronounced dead at the scene. Colour Sergeant Dura was taking part in a road move when the Warrior tracked armoured vehicle he was travelling in was hit by an improvised explosive device.

He received medical treatment at the scene; however he died of his wounds while being taken to the military hospital at Camp Bastion. The two Marines were taking part in a foot patrol and had moved on to the roof of a compound when there was an attack by insurgents armed with rocket-propelled grenades and they were badly wounded.

Both marines received immediate medical attention and were moved to a secure location before being put on a helicopter to be transferred back to Camp Bastion, however both died from their injuries during the flight. X-Ray Company was conducting an operation alongside Afghan National Army troops to dominate areas posing a dangerous threat to British forces and the local Afghan population. The men who were killed were members of the Quick Reaction Force QRF which was working in support of the company operation.

The members of the QRF were talking to locals when a year-old boy pushed a wheelbarrow containing an explosive device toward them, which was then detonated killing the marines and killing and injuring a number of children and civilians. It is thought that the boy did not know about the explosives in the wheelbarrow and was an unsuspecting victim of the blast.

He was at a Forward Operating Base in the Gereshk area of Helmand province when he was fatally wounded when the gun position he was commanding came under attack. He received immediate medical treatment and was then taken by helicopter to the International Security Assistance Force's military hospital at Kandahar, but died shortly after arrival. Rifleman Nash was covering his comrades from the roof-top of a building in a compound when he was wounded.

He was treated on the scene and then flown to Camp Bastion for further treatment, but died from his injuries. At about hours, just west of Lashkar Gah in Helmand Province, a BvS 10 Viking armoured personnel carrier was disabled by an explosion which injured 3 personnel on board. When Cpl Deering, who was a Viking Mechanic, approached the disabled vehicle to assess the damage, there was a second explosion which killed him instantly.

Corporal Liam Elms , aged 26, from Zulu Company, 45 Commando, Royal Marines was killed by an explosion while taking part in a local area patrol alongside Afghan National Army troops on the afternoon of 31 December in the Sangin district, Helmand province, Afghanistan.

He was 2IC of a section taking part in a vehicle patrol alongside members of the Afghan National Army when his vehicle was struck by an improvised explosive device. Victor Company 45 Commando was conducting a deliberate offensive patrol alongside the Afghan National Army to destroy a key Taliban command cell.

While establishing a vital fire-support location to protect his colleagues advancing on a Taliban defensive position, Mne Mackin was killed by an enemy Improvised Explosive Device. The MoD subsequently confirmed that the men died as a result of a 'Blue on Blue Friendly fire ' incident, thought to involve a Javelin missile.

He was 21 years old and from Saltash, Cornwall. Acting Corporal Robinson was on a patrol to dominate ground with his Operational Mentoring and Liaison Team and the Afghan National Army platoon with whom he had been operating since September when he was killed as a result of enemy fire during an ambush north of Sangin District Centre.

He was 31 years old. Corporal Nield died from injuries sustained from an explosion, believed to have been caused by an RPG , possibly fired by an Afghan National Army soldier, [] during a fire-fight while on a deliberate operation involving a joint UK and Afghan National Army patrol north of Musa Qala. The marine died as a result of wounds sustained from enemy fire in an area to the south west of Sangin, in Northern Helmand.

He was part of a patrol operating in support of an Explosive Ordnance Disposal Team. The Patrol was ambushed by Taliban fighters and Marine Smith was struck by small-arms fire, however despite receiving medical help from his colleagues he died of his wounds while being flown to hospital.

The soldiers died from wounds sustained as a result of their Snatch Land Rover being struck by an enemy IED during an escort operation in the Gereshk district of Helmand province. Marine Laski was taking part in a foot patrol to provide security to the local Afghan community. When crossing open ground they were engaged by enemy fire and during the engagement that followed Marine Laski was struck by a bullet.

Despite the best efforts of all involved he failed to recover consciousness and died with his family round him. He received immediate medical attention from the medics within his team but died at the scene. The men were involved in a vehicle movement to the west of Garmsir in Helmand province, southern Afghanistan when the Jackal MWMIK they were travelling in was struck by an explosive device and destroyed, killing both men.

Lance Sergeant Fasfous was killed instantly as a result of an explosion while taking part in a foot patrol alongside the Afghan National Army in the vicinity of FOB Keenan , north east of Gereshk in Helmand province.

Corporal Binnie was killed during a fire-fight with insurgents which occurred during reassurance patrol with the Afghan National Army in the vicinity of Woqab, close to Musa Qal'eh in Helmand Province.

The two Service personnel were killed by a suicide bomber during a patrol in Gereshk , Helmand province , in the afternoon of Thursday 7 May The men had dismounted from their Snatch Vixen Land Rover when they were approached by the bomber on a motorbike, who then immediately detonated his device.

Lieutenant Mark Evison, aged 26, from the 1st Battalion Welsh Guards died peacefully on 12 May in Selly Oak Hospital , Birmingham , as a result of a gunshot wound sustained during a patrol in the vicinity of Haji Halem, Helmand province, Afghanistan, on 9 May The resulting explosion killed Marine Mackie instantly and seriously injured his crewman.

While on a foot patrol near Sangin in Helmand Province Fusilier Suesue was fatally injured by a gunshot. Fusilier Suesue was 28 years old and originally from Fiji. Lance Corporal Hill was on a deliberate operation near Garmsir in Helmand province when there was an explosion which killed him instantly. The soldier was on a patrol near Gereshk , when he was killed by an explosion. When his section became pinned down by accurate rifle fire from two sides Pte McLaren pushed forward to obtain a better fire position to relieve his section, but was killed by an explosion from an improvised explosive device.

Lieutenant Paul Mervis, a platoon commander from The 2nd Battalion the Rifles was on a foot patrol near Sangin, northern Helmand Province, when he was killed as a result of an explosion from an improvised explosive device, on the morning of 12 June Major Birchall was travelling in a Jackal MWMIK which was the second vehicle in a group of three which were involved in a routine patrol to deliver supplies and check on his men in the checkpoints around Basharan. Although he survived the initial blast and received immediate medical attention at the scene, Major Birchall died of his injuries before he could be extracted to medical facilities.

Another six troops were injured by the blast. Pte Laws had been involved in a dismounted IED search team and had periodically been dismounting and remounting the vehicle as it stopped and started along a road. It was immediately after he had remounted and the vehicle had just moved off when it was struck. He was aged Several other members of the patrol were injured in the explosion.

Captain Ben Babington-Browne , aged 27, from 22 Engineer Regiment, Royal Engineers, died in an incident in Afghanistan, Monday 6 July when the helicopter he was in crashed [] while taking off from a US forward operating base in Zabul province.

It was "determined that the crash did not occur as a result of enemy fire". Rifleman Daniel Hume, aged 22, of the 4th Battalion The Rifles, was killed by a contact explosion while on a foot patrol near Nad e-Ali, Helmand province on 9 July Private John Brackpool , aged 27, formally of The Princess of Wales's Royal Regiment and serving as a reservist with the 1st Battalion Welsh Guards , died on 9 July as a result of a gunshot wound.

He was shot and killed while he was on sentry duty on a compound that had recently been secured as part of Operation Panchai Palang , near Char-e-Anjir, just outside Lashkar Gah, in Helmand Province.

He died in an explosion as he was travelling in the lead vehicle of a group of BvS 10 Vikings. The men were conducting a routine patrol from FOB Wishtan when at approximately hrs a member of the patrol accidentally detonated an improvised explosive device IED which fatally wounded him and injured seven other members of the patrol.

The soldiers then recovered their wounded and dropped back to attend to them and await the assistance of the medical Quick Reaction Force QRF. At approximately hours, just as the QRF arrived, a second, more powerful device was detonated in the area where the wounded men were being treated, killing another three members of the platoon including Rifleman Murphy who was carrying his close friend Rifleman Simpson, to safety after he had been wounded in the first explosion.

Attempts to evacuate the injured soldiers were further hampered by IEDs on the possible helicopter landing areas at the scene of the explosion so the men had to be evacuated to the FOB, however more IEDs had been placed by the Taliban on the route back to FOB Wishtan.

Cpl Etchells, who was aged 22 and from Mossley, Greater Manchester, was killed as a result of an explosion that happened while on a foot patrol near Sangin, northern Helmand Province. Guardsman Christopher King, from the 1st Battalion Coldstream Guards , who had been attached to the Number 2 Company, 1st Battalion Welsh Guards since late , was killed on 22 July , as a result of an explosion while on a dismounted patrol in Nad Ali District, Helmand Province.

While taking part in Operation Panchai Palang , Bombardier Hopson was part of a patrol tasked to reconnoitre a suitable area for a polling station in the forthcoming Afghan presidential elections. He was killed as a result of an explosion that happened while on a vehicle patrol in Babaji District, southern Helmand province.

Another British soldier remains in a critical condition following the attack. Private Williams' platoon was attempting to recover the body of an Afghan National Army warrior who was killed earlier in the day, when an IED exploded killing Pte Williams. Lance Bombardier Hatton had been clearing a route to a helicopter landing zone to enable an earlier casualty to be airlifted to medical aid when he was caught by an IED blast and was wounded.

As a result of this Pvt Hunt's head struck the vehicle and despite wearing his drivers protective helmet Pvt Hunt sustained a serious injury from which he never recovered consciousness. He was subsequently aero-medically evacuated to the Royal Centre for Defence Medicine in Selly Oak Hospital so his family could be with him when he died. The three men were taking part in a foot patrol near Sangin in Helmand province when Lance Corporal James Fullarton, who was the Section Commander was badly hurt by a roadside bomb.

Fusiliers Annis and Carter went to his assistance, but a second IED detonated, killing all three soldiers. As Serjeant McAleese attempted to assist Young there was a secondary explosion which fatally injured both men.

While on a foot patrol in Sangin district, Helmand province, on Saturday 15 August Fusilier Bush was attempting to rescue Sergeant Simon Valentine when there was a secondary explosion which seriously injured him. It was clear he would not recover from his injuries and he was evacuated to Selly Oak, where he died with his close family around him.

A Royal Marine died following an explosion while on a foot patrol near Gereshk in Helmand Province, Afghanistan, in the early hours of Saturday 29 August His family have asked for no further information to be released. Lance Corporal Richard James Brandon , operating with The Light Dragoons Battle Group, was killed as a result of an explosion that happened while on a vehicle move in the Babaji district, central Helmand province, on the evening of 2 September Kingsman Jason Dunn-Bridgeman from 2nd Battalion The Duke of Lancaster's Regiment was killed in a firefight with the enemy during a foot patrol in the Babaji district of Helmand province on 13 September Acting Serjeant Stuart McGrath , from 2nd Battalion The Rifles was killed as a result of an explosion that happened while on a foot patrol in the Gereshk district, central Helmand province, on the afternoon of 16 September Private James Prosser from 2nd Battalion The Royal Welsh was killed as a result of an explosion that happened during a vehicle patrol in Musa Qaleh district, northern Helmand province on 27 September Guardsman Jamie Janes from 1st Battalion Grenadier Guards, was killed as a result of an explosion that happened while on a foot patrol near to Nad e-Ali district centre in central Helmand province on Monday 5 October On 8 December , he was announced as the th British soldier to die in Afghanistan in the year On 23 December, an investigation was started to the deaths of Lance Corporal Michael David Pritchard , aged 22, a member of the Royal Military Police who was attached to 3rd Battalion The Rifles, and Lance Corporal Christopher Roney aged 23, from 3rd Battalion the Rifles, who possibly died as a result of friendly fire "blue on blue" , the last one after a vicious firefight in Patrol Base Almas near Sangin in Helmand.

There had been British troops killed in Afghanistan since This casualty brought the number of British soldiers killed in the conflict since to , including in On 15 December, the official casualty toll up to the end of November was released by the Ministry of Defence: more than 1, members of the Armed Forces had been wounded in action in Afghanistan since the mission began in late

   

 

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