Chinese Drywall Testing

Analytical testing dots Chinese Drywall Testing

Test for Chinese DrywallALS Environmental offers a reliable test protocol for identifying odor and corrosion problems in drywall. The tests identify problems with drywall, generally reported as "Chinese Drywall," that initially affected many homes in the southeastern United States.

Laboratory tests may be used to confirm visual home inspections and to demonstrate that corrosion effects are due to drywall and not other items in the home (e.g. carpets, cleaners, paints, personal care products).

ALS Environmental has been studying this issue and testing both foreign and domestic drywall samples since February 2008. The laboratory has developed a suite of three analytical tests that may be used to identify defective drywall products. These three tests are included in both the CPSC and Florida Department of Health (FL DOH) guidance documents for a positive case definition of corrosive drywall.

NEW - As of August 27, 2010, the Federal Interagency Task Force on Problem Drywall, comprised of staff members from the U.S. Consumer Product Safety Commission (CPSC) and the U.S. Department of Housing and Urban Development (HUD), asserts that elemental sulfur is the marker most directly correlated with reports of problem drywall in a home. For a complete summary of the August 27, 2010 interim guidance revision on Chinese Drywall, visit the CPSC's Drywall Information Center.Analytical testing dots

Chinese Drywall Test Package

1. Elemental Sulfur Test for Chinese Drywall

A scientist prepares the GC/MSD for testing Chinese drywall samples for the presence of elemental sulfur.A scientist prepares the GC/MS for testing Chinese drywall samples for the presence of elemental sulfur.

The drywall in question contains a naturally occurring allotrope of elemental sulfur— orthorhombic cyclooctasulfur (S8). ALS Environmental has developed a novel techniques to analyze for S8 in drywall:

  1. GC/ECD Test (Gas Chromatography/Electron Capture Detection)
  2. GC/MS Test (Gas Chromatography/Mass Spectrometry)

The GC/ECD test is a robust, low-cost analysis that allows clients to screen a large number of drywall samples for S8. Because drywall used in home construction can be from mixed sources, submission of multiple samples from one suspect home may be done to reduce the risk of false negative results. Roughly 5g (approximately 2”x2”) of bulk drywall material is all that is required for the GC/ECD analysis. Results are reported in units of mg/kg. A positive result above 10 mg/kg is indicative of corrosive drywall, according to the FL DOH's Case Definition (12-18-09) for Drywall Associated Corrosion in Residences.

Cyclooctasulfur
Cyclooctasulfur molecule
structure, S8

Read more about the Elemental Sulfur Test...

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2. Hydrogen Sulfide Emission Test for Chinese Drywall

A GC/MSD is used for the hydrogen sulfide emission test on Chinese drywallA GC/SCD is used for the hydrogen sulfide emission test on Chinese drywall.

Researchers at ALS Environmental developed an innovative chamber test procedure for the measurement of hydrogen sulfide at ultra low levels in suspect drywall. Hydrogen sulfide is a contributor to copper pipe corrosion and has a characteristic “rotten egg” smell with an extremely low odor threshold.

Chromatogram from Gas Chromatography/Sulfur Chemiluminescence Detector (GC/SCD) Analysis of Chinese Drywall Chamber Sample (1 mL injection of 1L chamber containing 50g defective Chinese drywall, incubated for 48 hours at 37ºC.)

Chromatogram from Gas Chromatography/Sulfur Chemiluminescence Detector (GC/SCD) Analysis of Chinese Drywall Chamber Sample (1 mL injection of 1L chamber containing 50g defective Chinese drywall, incubated for 48 hours at 37ºC.)

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3. Copper Corrosion Confirmation Test for Chinese Drywall

A copper corrosion jar test is performed using a copper tube and Chinese drywall sample.
A copper corrosion jar test is performed using a copper tube and Chinese drywall sample.

A jar test is used to visually document the phenomenon of copper corrosion in the presence of test drywall samples. A copper tube is placed in the jars with the drywall sample.

Jar Test for Chinese Drywall Testing

Example of sample jar test (middle), showing black copper corrosion. Sample results may be qualitatively compared to a negative control (unaffected domestic drywall—on left) and a positive control (known affected Chinese drywall in the middle and on the right).

View larger image

A copper tube after being exposed to normal drywall.

A copper tube after being exposed to normal drywall.

A black, corroded copper tube after being exposed to problem drywall.

A black, corroded copper tube after being exposed to problem drywall.

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How to Submit Samples

It is recommended to take a 5" x 5" piece of drywall. Place the drywall sample and seal it in a zipper storage bag (such as Ziploc®), then seal it again with another zipper bag (double bagged).

Next, complete a drywall chain of custody form. This form is located on the top-right of this page as a PDF file- which can be printed and filled out by hand. The shipping address and contact information is located on the form.

Due to the constantly evolving nature of this work, please email or call the Simi Valley, CA laboratory at 805-526-7161 for pricing and the latest technical information on drywall testing.

For the latest updates on the Chinese Drywall situation in Florida, please visit website for the Florida Department of Health or the CPSC’s Drywall Information Center.

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See frequently asked questions (FAQs) for Chinese drywall...

Watch a video presentation on Chinese drywall (from Technical Symposium on Corrosive Imported Drywall)

Learn how a lab can help you identify problem Chinese drywall...

Read more about Chinese drywall testing, sulfur testing, and Chinese drywall problems

Learn more about carbonyl sulfide, carbon disulfide, hydrogen sulfide, or view more sulfide analytes.

 

ALS Environmental is an independent, third-party testing laboratory that does not endorse other companies' products or services.