Draft Identification of Problematic Drywall: Source Markers and Detection Methods

Figure 6.1 Scatterplot Showing the Relationship Between a) S 8 Concentration (mg/kg) and Hydrogen Sulfide Flux and b) Strontium (mg/kg) and Hydrogen Sulfide Flux Figure 6.2 Scatterplot Showing the Relationship between S 8 Concentration (mg/kg) and a) Sulfur Dioxide Emission Rate and b) Carbon Disulfide Emission Rate Figure 6.3 Correlation of S 8 and Strontium in a) Catalog Samples and b) Homes in the 51-home Study Figure 6.4 Comparison of S 8 Concentrations (mg/kg) and Chamber-based Corrosion Rates (A/30d) Figure 6.5 Comparison of Strontium Concentrations (mg/kg) and Chamber-based Corrosion Rates (A/30d) Figure 6.6 Comparison of House-average S 8 Concentrations (mg/kg) and Corrosion Rates at the AHU Air Register from the 51-home Study Figure 6.7 Scatterplot Comparing Strontium Concentrations (mg/kg) and Silver and Copper Corrosion Rates (A/30 days) at the AHU Air Register A/30d angstroms per 30 days Ag 2 S silver sulfide AgCl silver chloride AHU air handling unit CPSC U. S. Consumer Product Safety Commission CS 2 carbon disulfide CuO copper oxide Cu 2 S copper sulfide DFTPP decafluorotriphenylphosphine DRIFTS diffuse reflectance infrared Fourier transform spectroscopy ERT Environmental Response Team FTIR Fourier transform infrared spectroscopy GC/MS gas chromatography/mass spectrometry GC/ECD gas chromatography electron capture detector H 2 O 2 hydrogen peroxide H 2 S hydrogen sulfide HCI hydrochloric acid HNO 3 nitric acid ICP inductively coupled plasma ICP-AES inductively coupled plasma-atomic emission spectrometry LOD limit of detection LPM liters per minute mg/kg milligram per kilogram mL milliliter PTFE polytetrafluoroethylene REAC Response Engineering and Analytical Contract RH relative humidity S 8 orthorhombic sulfur SO 2 sulfur dioxide SOP standard operating procedure SRM standard reference materials XRF x-ray fluorescence °F degrees Fahrenheit L microliter m micrometer 1.1 BACKGROUND The U.S. Consumer Product Safety Commission (CPSC) has been investigating homeowner reports of corrosion and adverse health effects in homes constructed with problematic wallboard that has also been termed 'Chinese drywall'. To date, CPSC has received approximately 3,300 homeowner reports from 37 states. The vast majority of complaints are from people with homes around the Gulf Coast and coastal Virginia. CPSC initiated a multi-track investigation to examine health and safety concerns potentially associated with this building product. As part of this investigation, Environmental Health & Engineering, Inc. (EH&E) conducted a 51-home study in the summer of 2009 to characterize the relationship between source markers, gas concentrations, building dynamics, and corrosion. A complete report outlining the methods, results and findings of that study are …