ANSI/ASHRAE Standard 62-1999, “Ventilation for Acceptable Indoor Air Quality,” sets minimum ventilation rates and other requirements for commercial and institutional buildings.
The filtration requirements in addendum s are intended to reduce the rate of dirt accumulation on ventilation system components that are likely to become wet, such as cooling coils.
“Dirt accumulation on wet surfaces provides a substrate that may lead to microbial growth, which could cause the ventilation system to become a source of contaminants,” said Andrew Persily, chair of the committee writing the standard.
One other addendum was recommended by the committee for publication at the society’s 2001 winter meeting held in Atlanta, Jan. 27-31. Addendum 62 q modifies several definitions for clarity, as well as deletes several definitions that are not used in the standard or which are already defined in standard dictionaries.
These publication recommendations are subject to the approval of the ASHRAE Standards Committee and Board of Directors, and followed by a 15-day appeals process. In other business, the committee recommended three addenda for public review.
Among them, addendum x was recommended for a second public review. This addendum revises the humidity control requirements contained in Section 5.10, as well as clarifies the standard’s existing recommendations and requirements to ensure that the building envelope does not contribute to IAQ problems, according to Persily.
In addition, the committee recommended addendum k for a third public review. This addendum describes how the requirements of the standard should be applied to existing buildings.
Finally, the committee recommended addendum ab for a first public review. This addendum addresses equipment that generates contaminants and the need to duct this equipment to the outdoors.
The public review recommendations are subject to review by ASHRAE’s Standards Project Liaison Subcommittee.
The committee also voted to send several draft addenda out for ASHRAE technical committee review, a preliminary step before the public review process. Among these was addendum 62n, which revises the standard’s ventilation rate procedure that contains requirements on how to determine outdoor air ventilation requirements in buildings.