ASHRAE Publishes 2004 Residential IAQ Standard

December 21, 2004

ATLANTA—ANSI/ASHRAE Standard 62.2-2004 was published by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, containing the first changes (in the form of two addenda) resulting from continuing maintenance proposals from the public.

The American National Standards Institute Board of Standards Review recently denied appeal of the standard, thereby upholding its earlier approval.

ANSI/ASHRAE Standard 62.2-2004 - Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings - is the only nationally recognized indoor air quality standard developed solely for residences, according to ASHRAE.

The 2004 standard no longer contains combustion appliance backdrafting test requirements. The test included in the 2003 standard was based on the best industry-accepted method found in the National Fuel Gas Code but questions arose about its application to solid-fuel burning appliances, according to David Grimsrud, ANSI/ASHRAE Standard 62.2-2004 committee chair.

There also was concern about the test not being possible to perform until a home's completion, opening the potential for remedial balancing at a difficult stage of construction and sale, said Grimsrud.

While the test requirements have been eliminated, the standard sets an upper limit of exhaust flow to 15 cfm/100 square feet when natural-draft combustion appliances are present.

The standard also contains a change in climate zone terminology from "severe cold climate" to "very cold," which is now defined as one that has more than 9,000 65°F degree-days.

This makes the standard's climate definitions consistent with proposed revisions to the International Code Council climate zone definitions, simplifying implementation of Standard 62.2 into code, said Grimsrud. ASHRAE has proposed that the standard be included in the 2006 International Residential Code.