Press Statement on Corrosion in Homes and Connections to Chinese Drywall

U.S. Consumer Product Safety Commission

November 23, 2009

Press Statement on Corrosion in Homes and
Connections to Chinese Drywall

Results from a major indoor air study of 51 homes are being released today along with
initial reports from two studies of corrosion in homes with Chinese drywall. We now can
show a strong association between homes with the problem drywall and the levels of
hydrogen sulfide in those homes and corrosion of metals in those homes.

By identifying this association, the Interagency Drywall Task Force can now move
forward to develop protocols that will identify homes with this corrosive environment
and can determine the effectiveness of remediation methods. The Task Force continues to
work with Congressional and White House officials to determine the best approaches to
design and fund these identification and remediation efforts to help the families dealing
with this issue.

“We now have the science that enables the Task Force to move ahead to the next phase –
to develop both a screening process and effective remediation methods. Ongoing studies
will examine health and safety effects, but we are now ready to get to work fixing this
problem,” said U.S. Consumer Product Safety Commission Chairman Inez Tenenbaum.
The Studies

The 51 home study contracted by CPSC was done by Environmental Health &
Engineering (EH&E), an internationally known environmental testing firm based in
Massachusetts.

In addition, today two preliminary reports on corrosion safety issues are being released.
The Sandia National Laboratories’ (SNL) Materials and Engineering Center is studying
the long-term electrical safety hazards of conductor metal components. The National
Institute of Standards and Technology (NIST) is studying the corrosion effects on fire
safety components taken from complaint homes.

Findings
EH&E compared 41 “complaint” homes in five states selected from CPSC’s consumer
incident report database, with 10 noncomplaint homes built around the same time in the
same area as the complaint homes. Homes were sampled between July and September
2009.

The EH&E findings are that hydrogen sulfide gas is the essential component that causes
copper and silver sulfide corrosion found in the complaint homes. Other factors,
including air exchange rates, formaldehyde and other air contaminants contribute to the
reported problems.

In ways still to be determined, hydrogen sulfide gas is being created in homes built with
Chinese drywall. Earlier studies found large amounts of elemental sulfur in the Chinese
drywall. CPSC is investigating drywall from other sources that may mimic the problems
found with Chinese drywall. CPSC is meeting with drywall manufacturers and others
who are studying this issue to take their findings into consideration.

EH&E exposed copper and silver test strips, known as coupons, in homes for a period of
about two weeks. The coupons showed significantly higher rates of corrosion in
complaint homes than in the control homes. The dominant species of corrosion on the
coupons was copper sulfide and silver sulfide, as determined by additional laboratory
tests. Visual inspection and evaluation of ground wire corrosion also revealed
statistically significant greater ground wire corrosion in complaint homes compared to
non-complaint homes.

The EH&E study also found that by using hand-held x-ray fluorescence (XRF) and
Fourier Transform Infrared (FTIR) instruments, they were able to detect markers that
could identify Chinese-made dry wall at a sheet-by-sheet level.

While drywall-related corrosion is clearly evident, long term safety effects are still under
investigation. Like the EH&E study, initial reports available today from SNL and NIST
show copper and silver sulfide corrosion on samples of metal taken from homes with
problem drywall. These ongoing investigations will help the CPSC identify the nexus of
problem drywall and long term safety issues.

In addition, the EH&E study found elevated formaldehyde readings in both the control
and complaint homes. This is typical for new, more air-tight homes due to items such as
cabinets and carpets which emit formaldehyde. Both formaldehyde and hydrogen sulfide
are known irritants at sufficiently high levels. The concentrations measured in this study
were below those levels. Investigators believe that the additive or synergistic effects of
these and other compounds in the subject homes could cause irritant effects evident in the
homes.

Next Steps
First, CPSC continues to search for homes exhibiting the corrosion and health effects
under study. In addition to a direct call to consumers, CPSC is contacting governors of all
states, all territories and the District of Columbia, to ensure that all homes with these
problems have been reported to CPSC.

Second, the Interagency Task Force established an Identification and Remediation
Protocol Team of scientists and engineers. This Team will use the results of the EH&E
study and other information to design a cost-effective screening protocol to identify
homes with this problem. Professional air sample testing, and destructive testing of
drywall can carry high costs. The Protocol Team will develop quick, cost-efficient
evaluation methods to identify homes with these problems. The Protocol Team will also
look at remediation protocols, to see what cost-efficiency improvements to current
remediation practices, if any, may be available, and what guidance should be issued on
doing the work safely.

Third, investigations currently underway by Lawrence Berkeley Laboratories, SNL and
NIST and others will continue toward identifying additional information on any possible
long-term health and safety issues.

The Identification and Remediation Protocol Team will use information from the EH&E
study and other information to begin evaluating remediation protocols. Homes that have
undergone remediation are expected to yield valuable information that will be helpful for
homeowners.

The Interagency Task Force is actively talking to Congressional and White House
officials about the best approaches to design and fund both the Identification and
Remediation efforts.

Other Ongoing Efforts
The Interagency Task Force, working with U.S. Customs and Border Protection, is
monitoring imports of possible Chinese drywall. We believe that no new Chinese drywall
has entered the United States in 2009. Owners of known U.S. inventories of Chinese
drywall have been notified of this ongoing investigation. They have indicated that the
drywall boards will not be sold. Further, CPSC has secured the cooperation of the
Chinese Government to help identify the sources and causes of this problem.
CPSC is working with an ASTM committee that has just initiated discussions on the
formulation of a proposed new standard on inspection of drywall for air quality issues.
Recommendations to Affected Homeowners

To date, CPSC has received more than 2000 reports from 32 states, the District of
Columbia and Puerto Rico from consumers and homeowners concerned about problem
drywall in their homes.

Homeowners who believe they may have problem drywall should immediately report to
CPSC by calling 800-638-2772 or logging on to www.CPSC.gov. Hearing- or speechchallenged
individuals may access the phone number through TTY by calling the toll-free
Federal Relay Service at 800-877-8339.

Federal and state health experts suggest these steps to improve indoor air quality and to
reduce exposure to substances that can cause health concerns:
o Open windows as much as possible to let in fresh air.
o Keep the temperature inside homes at the lowest comfortable setting.
o Run the air conditioner or dehumidifier.
o Also, spend as much time outdoors in fresh air as possible.
o Do not smoke, and especially do not smoke indoors. Cigarette smoke contains,
among other contaminants, formaldehyde.

To read the technical research reports or for more information, log on to
www.DrywallResponse.gov.