ATLANTA, GA — The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) has recommended for publication an addendum to its ventilation standard that would clarify requirements for equipment-related particulate filtration.

ANSI/ASHRAE Standard 62-1999, “Ventilation for Acceptable Indoor Air Quality,” sets minimum ventilation rates and other requirements for commercial and institutional buildings. ASHRAE said that the filtration requirements in proposed 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.

Andrew Persily, chair of the committee writing the standard, said, “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.”