A proposed new ASTM standard will allow for a mold-resistance rating to be given to specific exterior building materials based on how the materials perform to a standard test method, ASTM announced.
The proposed new standard—ASTM WK32079, Test Method for Determination of Mold Growth on Building Products Designed for Exterior Applications Using an Environmental Chamber and Direct Inoculation—is being developed by Subcommittee G03.04 on Biological Deterioration, part of ASTM Committee G03 on Weathering and Durability.
ASTM WK32079 describes an environmental chamber and the conditions of operation to evaluate in a four-week period the relative resistance to mold growth on building products to be used outdoors, the organization said.
Judy LaZonby, president and technical director of The MicroStar Lab Ltd. and chairman of G03.04 and D01.28 on Biodeterioration, said the standard will be “more aggressive” than a proposed standard currently being developed by ASTM D01.28 for interior applications.
“Material that is exposed to outdoor weather conditions must withstand more severe challenges than materials designed for interior exposures,” LaZonby said. “If a chamber method is going to be useful in determining a mold-growth rating for exterior products, the challenge will need to be more severe than that used for evaluating interior surfaces.”
ASTM said primary users of the standard will be manufacturers of building materials, chemical companies with mold-resistant chemistries, and independent laboratories evaluating mold-resistant products.
All interested parties are invited to join G03.04 in the ongoing development of the WK32079 standard. LaZonby said many of the individuals currently involved in the development of WK32079 are primarily interested in indoor mold growth. She encouraged the participation of more individuals whose area of expertise is in mold growth on exterior building applications.
LaZonby can be reached by email at firstname.lastname@example.org.
More information on ASTM membership: www.astm.org/JOIN.