ATLANTA - The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) is currently accepting public input on more than 35 proposed addenda to standards, as well as a proposal to withdraw Standard 52.1.

Addenda to various standards - including 15, refrigerant safety; 34, classification of refrigerants; 55, thermal comfort; 90.1, energy efficiency; 62.1, ventilation; 62.2, residential ventilation; and 135, BACnet - are open for review, as are seven standards and one guideline.

Among them is the proposed withdrawal of ASHRAE Standard 52.1-1992, Gravimetric and Dust-Spot Procedures for Testing Air-Cleaning Devices Used in General Ventilation for Removing Particulate Matter. According to ASHRAE, the most important features of this standard, dust-holding capacity and arrestance, have been incorporated into Standard 52.2-2008, Method of Testing General Ventilation Air Cleaning Devices for Removal Efficiency by Particle Size. The only unique features remaining in Standard 52.1 are the dust-spot efficiency tests - now replaced by particle-size efficiency tests in 52.2 - and a renewable filter test not used by the industry for decades, according to Monroe Britt, committee chair.

Among the proposed addenda to Standard 90.1 is addendum ap, which would modify the requirements for demand control ventilation; adding the demand controlled ventilation requirements to the simplified approach in order to keep the stringency of this path the same as the mandatory plus prescriptive path of compliance. Also proposed is a change to addendum af to modify energy savings requirements to recognized varied piping material pressure drops.

Six proposed addenda to Standard 62.1 are open for comment, including a proposal regarding outdoor air cleaning. Addendum 62.1c adds significant air cleaning requirements in many locations within the United States. Regarding particulate matter 2.5 micrometers and smaller, for buildings in those U.S. locations established as non-attainment for PM2.5 by the U.S. Environmental Protection Agency, 62.1c would require that the ventilation system include particle filters rated at least MERV 11 (installed between the outdoor air intake and the occupied zone). Regarding ozone air cleaning, the proposed addendum would require that the ventilation system include ozone air cleaners rated for at least 40 percent ozone removal efficiency.

For more information, visit www.ashrae.org.

Publication date:10/06/2008