ATLANTA - Five proposed addenda to the American Society of Heating, Refrigerating and Air-Conditioning Engineers’ (ASHRAE’s) ventilation standard are open for public review until April 30, 2007.

ANSI/ASHRAE Standard 62.1, Ventilation for Acceptable Indoor Air Quality, sets minimum ventilation rates and other requirements for commercial and institutional buildings.

Proposed addendum 62.1c would add air cleaning requirements to section 6 of the standard. If approved, systems in non-attainment areas for particulate matter with diameter 2.5 microns (PM2.5) would need to use intake air filters with minimum efficiency reporting value (MERV) 11.

The use of better filtration would improve indoor air quality, according to Dennis Stanke, chair of the Standard 62.1 committee.

In addition, systems in areas designated by the U.S. Environmental Protection Agency (EPA) as “serious,” “severe,” or “extreme” non-attainment areas for ozone would require ozone air cleaners with at least 40 percent efficiency.

“The standard has required 40 percent efficient ozone air cleaning for some of these high-ozone areas since 2004, but designers have had difficulty determining when this requirement applies,” Stanke said. “If more designers understood which geographical areas require ozone air cleaning and used 40 percent ozone air cleaners in those areas, indoor air quality would be improved for many people.”

Also open for public comment is addendum 62.1i, which would change minimum outdoor airflow requirements for zones with environmental tobacco smoke (ETS) as described in section 6.2.9.

“This issue attracted significant interest during its first public review period, resulting in many comments,” Stanke said.

Based on public input, the current addendum was revised and now requires that ETS be supplied with more outdoor air than areas with the same occupancy category but without ETS (i.e., ETS-free areas). The outdoor airflow rate would be determined using “engineered methods with the approval of the authority having jurisdiction.”

“Some committee members feel that including a requirement for increased outdoor airflow would imply that dilution ventilation can be used to achieve acceptable IAQ in the presence of ETS, and that the ‘engineered methods’ requirement places an undue burden on local authorities,” Stanke said. “The majority, however, feels that removing all reference to outdoor airflow in ETS would mean that any outdoor airflow rate - even a rate below that required for ETS-free areas - would comply with the standard, and that local code authorities must always approve engineered solutions. We’ll see what the public thinks based on this second public review.”

Other 62.1 addenda open for review are:

• Addendum 62.1a - addresses compliance issues that may result from unclear wording or phrasing in section 5.

• Addendum 62.1b - clarifies informative language in Appendix C, D, and F.

• Addendum 62.1d - adds the following occupancy categories to Table 6-1: kitchens, banks and bank lobbies, breakrooms, sorting, packing, light assembly, general manufacturing, and storage rooms (dry).

Proposed addenda to ASHRAE standards are available during public review periods. To read the addenda or to comment, visit www.ashrae.org/publicreviews.

Publication date:04/02/2007