Small-Chamber Measurements of Chemical-Specific Emission Factors for Drywall

Abstract

Imported drywall installed in U.S. homes is suspected of being a source of odorous and potentially corrosive indoor pollutants. To support an investigation of those building materials by the Consumer Products Safety Commission (CPSC), Lawrence Berkeley National Laboratory (LBNL) measured chemical-specific emission factors for 30 samples of drywall materials. Emission factors are reported for 75 chemicals and 30 different drywall samples encompassing both domestic and imported stock and incorporating natural, synthetic, or mixed gypsum core material. CPSC supplied all drywall materials. First the drywall samples were isolated and conditioned in dedicated chambers, then they were transferred to small chambers where emission testing was performed. Four sampling and analysis methods were utilized to assess (1) volatile organic compounds, (2) low molecular weight carbonyls, (3) volatile sulfur compounds, and (4) reactive sulfur gases. LBNL developed a new method that combines the use of solid phase microextraction (SPME) with small emission chambers to measure the reactive sulfur gases, then extended that technique to measure the full suite of volatile sulfur compounds. The testing procedure and analysis methods are described in detail herein. Emission factors were measured under a single set of controlled environmental conditions. The results are compared graphically for each method and in detailed tables for use in estimating indoor exposure concentrations.

Identifying Sources of Volatile Organic Compounds and Aldehydes in a High Performance Building

“…The drywall material produced a number of elevated VOCs with two (benzyl alcohol and propylene glycol) that exceeded the linear range of the analytical method. Drywall is typically a low VOC material [17,20] although fresh coatings such as paint or plaster can emitt VOCs during curing. The drywall samples tested in this study appear to be freshly painted because the edges were sealed with paint.…”

“…The approach has been used for a wide range of materials measuring both VOCs and carbonyls as described previously [8,17] and as summarized below.…”