Join us for the ASHRAE DL presentation. Today an acceptable indoor air quality is mainly defined by specifying the required level of ventilation in air changes per hour or the outside air supply rate. The increasing societal need for energy efficiency will often result in very tight buildings. This means that the amount of outside air supplied by infiltration is not enough to provide the required ventilation. In some standards, the required ventilation is based on adapted people (occupants) while other standards refer to un-adapted persons, who have just entered a room. Which approach is correct? Or should it depend on the type of space or occupancy? The present talk provides an overview and discusses the criteria used for specifying required ventilation rates and suggests ways of meeting the criteria in a more energy-efficient way by means of improved ventilation effectiveness, use of air cleaning, and by means of demand-controlled ventilation.
|Event Date||25-11-2020 6:00 pm|
|Event End Date||25-11-2020 7:00 pm|
|Cut off date||25-11-2020 7:00 pm|
HVAC system designers today have available computer programs which allow accurate determination of heating and cooling loads for specific building locations. In addition, there are programs which enable optimum choices for many system components (cooling coils, blowers, ductwork, etc.). There are, however, no generally accepted programs with which to determine the particulate matter indoor concentration and the air quality which will be obtained from given filter designs at specified locations. This is partially due to the complex nature of airborne particulate contamination and filtration processes, which have hindered the development of designer tools for filter systems. Air filters are often chosen on the basis of what worked somewhere. However, the design of HVAC air filter systems for particulate matter control is not entirely unquantifiable. Data are available on the nature and concentration of air contaminants in many locations world-wide, and on acceptable levels to be maintained indoors. Internationally accepted filter test standards exist which allow approximate calculation of the effect of filters on contaminant levels, and, in some cases, the expected energy consumption and cost impacts of filter systems. The proposed lecture is intended to illustrate what tools are now available to quantify the particulate matter and the design of filtration systems. Examples of performance calculations using existing data sources will be presented.
|Event Date||09-12-2020 6:00 pm|
|Event End Date||09-12-2020 7:00 pm|
|Cut off date||09-12-2020 6:00 pm|