While the phrase “Chinese drywall” has largely evaporated from news headlines lately, the federal interagency task force charged with investigating homeowner claims of off-gassing from imported drywall causing corrosion and negative health impacts has continued its work.
Leading the effort, the U.S. Consumer Products Safety Commission (CPSC) has periodically made public the findings of the investigation and accompanying research. In February 2010, we reported on a set of interim guidelines developed by the task force’s researchers for identifying problem drywall in homes. The CPSC recently released an amended set of guidelines that eliminates one of the steps that was included in the initial report.
The two-step method originally outlined required an on-site inspection that must show blackening of copper electrical wiring and/or air conditioner evaporator coils, as well as show that new drywall was installed in the home from 2001 to 2008. Once these conditions were confirmed, inspectors or contractors were advised to gather various items of corroborating evidence, which included testing drywall core samples for strontium levels in excess of 1200 parts per billion.
The CPSC now advises that testing for high strontium levels is not a useful method for identifying the presence of Chinese-manufactured drywall that contains high levels of the sulfur compounds responsible for home damage and health impacts. Although the task force’s research discovered that Chinese drywall contains higher concentrations of strontium and elemental sulfur, the task force has since determined that strontium does not play a role in the problems that have been reported as resulting from the use of drywall imported from China. In fact, testing for high levels of strontium could end in a false positive result, leading homeowners to undertake unnecessary and costly replacements.
The remaining identification methodologies, as outlined in the task force’s May 2010 report, “provide adequate options and assurance that a home may be correctly identified as containing problematic drywall,” according to the task force. Download a PDF of the complete revised interim guidance “Identification of Homes with Corrosion from Problem Drywall.”.
