ASHRAE is offering alternate ways to meet the HVAC construction ventilation requirements in its IAQ standard for existing buildings.

The American Society of Heating, Refrigeration and Air-Conditioning Engineers have proposed an addendum to its standard No. 62, “Ventilation for Acceptable Indoor Air Quality.”  

The addendum offers an alternate HVAC market compliance path for buildings where system performance information is unavailable or for use with small facilities.

“For existing buildings, it may be difficult to apply the ventilation rate procedure, particularly for buildings with multiple-zone recirculating ventilation systems,” said Roger Hedrick, chairman of the Standard 62.1 committee. “This is because determination of some of the values needed to calculate ventilation rates may be difficult or impossible because required information is not available. An example is system ventilation efficiency, used in equation 6.2.5.4.”

The public is allowed on the proposed change and other addenda at this website