Gas-phase air cleaners for use in HVAC systems
Many owners and operators of commercial and residential buildings need to reduce the levels of air contaminants such as ozone, sulfur dioxide, formaldehyde, and VOCs from the occupants’ breathing air. While particle filters are in common use, gas-phase air cleaner are less common and not as well understood. These air cleaners may be used to remove a wide variety of contaminants from the air. However, owner/operators need good information about which air cleaner works for which contaminants and, further, to determine which air cleaner is best for a given application.
Sorbents such as activated carbon are used in most air cleaners that remove gas-phase contaminants from the air. Different contaminants are removed by different sorbents. In addition, air cleaners contain different sorbents in various quantities (from grams to kilograms) and in various configurations (from flat panels to V-banks) all of which will have an impact on the filter’s performance. Thus, it is critical to have test data to document the performance of air cleaners. To meet this need, ASHRAE has published a new laboratory test standard giving the HVAC market its first gas-phase test standard for air cleaning devices. This method is ASHRAE 145.2-2011 “Laboratory Test Method for Assessing the Performance of GasPhase Air Cleaning Systems: Air Cleaning Devices.”