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Chinese Drywall Rotten Egg Smells, Corrosive Sulfur Gases, Rotten Egg Smells, Building Damage & Health Hazards in buildings

Chinese drywall problems in buildings: outgassing, damage, remediation costs:

This article series discusses Chinese Drywall, odors, indoor air quality hazards, corrosive outgassing, health hazards, and damage to copper building components such as copper electrical wiring and plumbing that may be caused by outgassing from Chinese Drywall used in construction in the U.S. Health complaints related to Chinese drywall outgassing include individual sensitivity to odors varies substantially, making odor reports inconsistent, but complaints include headaches, runny noses, and difficulty breathing.

We report on the following: financial relief for people who have to pay for Chinese drywall removal and building repairs. Authoritative information sources on Chinese Drywall. Chinese Drywall indoor air quality concerns include corrosive hydrogen sulfide or other gases & chemicals.

Chinese Drywall outgassing damage to electrical wiring, plumbing, air conditioner or heat pump corrosion as well as some building contents.

Find here: a list of sources of sulphur odors and sewer smells in buildings. How to identify odors or gases by type, source, and toxicity.

Noxious odors or smells in buildings can be diagnosed and cured. Names of Chinese Drywall Manufacturers; reports on Chinese Drywall Lawsuits.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?

Corrosive Drywall & "Chinese Drywall" Hazards: sources, causes, detection, & cures for corrosive drywall in buildings

Corroded copper tubing (C) Daniel Friedman B.S.The page top photo of blackened corrosion on an air conditioner cooling coil is from the U.S. CPSC warning to fire safety professionals.

[Click to enlarge any image]

Article Contents

Also see ODORS, SMELLS, GASES IN BUILDINGS-DIAGNOSIS & CURE

and see ODOR DIAGNOSIS CHECKLIST, PROCEDURE for a quick check that can help identify the source of smells in buildings

This article series discusses the diagnosis and cure of odors from a variety of sources including animals including pets, dogs, cats, or unwanted animals or dead animals, formaldehyde odors in buildings from building products or furnishings, plumbing drains, plastic or vinyl odors from building products, flue gases, oil tanks or oil spills, pesticides, septic odors, sewer gases, and even abandoned chemicals at properties.

Reader Question: What is causing oxidation and corrosion on copper pipes in my building?

Corroded copper tubing (C) Daniel Friedman B.S.In this article we include a few pictures of my copper lines running to the condenser coils in an air conditioner. This is after only 3 1/2 years in our new home. I contacted the builders of our home, and the said they have never used drywall from china. I tested my water with a water test kit for hydrogen sulfide, and the results were less than .3 ppm. And I can't find any reports of any cases like mine. - B.S.

B.S. makes the point that not all blackened copper or corroded copper components in buildings is easily nor necessarily traced to the Chinese Drywall outgassing problem. Some of these other sources of corrosion include:

Chinese Drywall Outgassing

Chinese drywall has received considerable attention in the U.S. as a source of odors, health hazards, and even corrosion of HVAC equipment, electrical wiring, and piping, found in North American homes renovated or built since 2001, and especially in homes built in 2006 and 2007.

The U.S. CPSC has received about 3,082 reports from residents in 37 states, the District of Columbia, American Samoa, and Puerto Rico who believe their health symptoms or the corrosion of certain metal components in their homes are related to problem drywall. State and local authorities have also received similar reports. - US CPSC.

As reported in the CPSC/CDC/EPA/HUD CPSC EXECUTIVE SUMMARY ON CHINESE DRYWALL, [paraphrasing and editing]

Testing by the Lawrence Berkeley National Laboratories (LBNL) demonstrated that certain Chinese samples had emission rates of hydrogen sulfide one hundred times greater than non-Chinese samples. CPSC staff modeling based on these results shows that estimated concentrations of the reactive sulfur chemicals in the indoor air of a home that are predicted to result from the presence of the drywall can be approximately a factor of ten times greater for certain Chinese samples than for the non-Chinese samples.

There were also tests made for possibly high levels of sulphur-reducing bacteria (SRB) in Chinese drywall, but as the summary continues:

... there appears to be no difference in the presence or absence of sulfur-reducing bacteria between the imported Chinese drywall and U.S. domestic drywall samples tested, including Chinese samples found by LBNL to have some of the highest reactive sulfur gas emissions.

As reported in the US CPSC PRELIMINARY EVALUATION OF DRYWALL CHAMBER TEST RESULTS,

The top ten reactive sulfur emitting drywall samples are from China. The patterns of reactive sulfur compounds emitted from drywall samples show a clear distinction between the Chinese drywall samples manufactured in 2005/2006 and NA drywall samples, with the exception of two Chinese samples C14 and C15, which have similarities to the NA emission profile.

The same study reports that by 2009 the Chinese drywall product corrosive sulphur gas and other emissions were substantially reduced:

The newer Chinese samples (manufacture date of 2009) demonstrate a marked decrease in sulfur emissions as compared to the 2005/2006 samples, and in some cases are similar to those of the NA [North American Manufacturer-produced drywall] samples.

Drywall outgassing, not bacteria, explain the sulphur smell

The March 26, 2010 US CPSC REPORT on CHINESE DRYWALL indicated that the odor source is not bacteria but outgassing of sulphur compounds. Quoting from that study (page 6),

While several organizations have hypothesized that SRB is responsible for production of reduced sulfur gases, only one peer-reviewed scientific paper was identified on this topic and it did not show a positive association between SRB and problem drywall. In the study published in 2010, subsequent to a poster in 2009, Hooper and colleagues describe the isolation of an iron oxidizing bacterium, Thiobacillus ferrooxidans, in Chinese drywall using a real-time polymerase chain reaction (RT-PCR) methodology (Hooper et al. 2010).

and from page 7.

Other groups, in non-peer reviewed literature, have also evaluated the role of SRB as a source of sulfur gases generated from problem drywall. In the October 2, 2009, issue of Builder Magazine, an interview with Sabre Technical Services advanced the position that the paper facing in problem drywall contains bacteria that are capable of producing reduced sulfur gases.

This position is contradicted by a limited study in which gamma irradiation was used to sterilize one piece of problem drywall and to examine the effects on corrosion potential. The study concluded that irradiation did not alter the corrosion potential of the drywall and, therefore, live bacteria did not play a role in copper corrosion (Cerro 2009).

In conclusion, there are conflicted studies of varying quality that have attempted to determine the role, if any, of microorganisms in the generation of sulfur-based corrosive gases emanating from problem drywall. This preliminary study demonstrates that SRB is culturable from a subset of both Chinese and U.S. manufactured drywall samples, but does not definitively determine if microorganisms are responsible (wholly or in part) for the generation of corrosive gases generated from problem drywall.

The effects of the outgassing of reactive sulfur compounds by Chinese drywall include

FHA-insured families experiencing problems associated with problem drywall may be eligible for assistance to help them rehabilitate their properties. HUD’s Community Development Block Grant (CDBG) Program may also be a resource to help local communities combat the problem.

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/cgibin/drywall.aspx. Hearing- or speech-challenged individuals may access the phone number through TTY by calling the toll-free Federal Relay Service at 800-877-8339.

Findings of Fact and Conclusions of Law Regarding Chinese Drywall - Germano Case

AN 10 APRIL 2008 COURT DOCUMENT reporting findings of fact and conclusions of law in GERMANO, ET AL. V. TAISHAN GYPSUM CO. LTD., ET AL., CASE NO. 09-6687 [108 page PDF] specifies general scientific findings on Chinese drywall which distinguish it from typical, benign drywall as the following: [Also see details and additional cases quoted at FINANCIAL AID: CHINESE DRYWALL LOSSES/REPAIRS]

  1. Chinese drywall has a significantly higher average concentration of strontium and significantly more detectable levels of elemental sulfur.
  2. Chinese drywall releases reduced sulfur gases.
  3. The sulfur gases released by Chinese drywall are irritating to the human body. Exposed individuals reported irritation of the eyes, respiratory system, and skin, among other things.
  4. The sulfur gases released by Chinese drywall cause offending odors in homes, making them hard if not impossible to live in.
  5. The sulfur gases released by Chinese drywall are corrosive to metals, particularly copper and silver.
  6. The corrosion on metals caused by the sulfur gases emitted by Chinese drywall causes premature failure of electrical & mechanical devices.
  7. The corrosion on metals caused by the sulfur gases emitted by Chinese drywall poses a fire risk

Names of Companies That Produced Outgassing Toxic Chinese Drywall

The Florida Sun Sentinel along with other news agencies such as the Los Angeles Times have reported (May 2010) that the U.S. CPSC has named five Chinese drywall Manufacturers, as the producers of corrosive H2S outgassing drywall and asked that these companies step up to their responsibilities to pay for repairs needed by U.S. homeowners who installed their products. Included among the five were the first five companies listed below in order of level of drywall outgassing:

  1. Knauf Plasterboard Tianjin Co. Ltd. [According to the Sun Sentinel, this manufacturer, Knauf Plasterboard Tianjin Co. Ltd., is settling cases with builders who have fixed homes containing the problem drywall.] The highest outgassing product was produced by this company in 2005. Drywall produced by this company in 2006 ranked in fifth highest outgassing position as well).
  2. Taian Taishan Plasterboard (drywall produced in China in 2006 and in 2009)
  3. Shandong Taihe Dongxin (drywall produced in China in 2005)
  4. Shandong Chenxiang GBM (C&K Gypsum Board): (drywall produced in China in 2006 and in 2009). Shandong Taihe Dongxin Co., Ltd. on September 10, 2007, changed its name to Taishan Gypsum Co., Ltd. [see GERMANO CHINESE DRYWALL CASE.]
  5. Beijing New Building Materials (BNBM): (drywall produced in China in 2009)

These companies are or were producers of drywall sold in the U.S. that has been tested and confirmed as emitting so much hydrogen sulfide it can cause pipes and wires to corrode and cause breathing or respiratory problems for home occupants.

Problem outgassing by drywall sold by these companies emits corrosive gans at as much as 100 times other brands. Typical home repair costs at 100 to 150 thousand dollars where this Chinese drywall was installed according to CPSC chairwoman. Inez Tenenbaum.

Alison Grant, a Boca Raton FL lawyer representing more than 500 homeowners affected by Chinese drywall says that the U.S. appeals to the manufacturers to stand behind their product won't help, and that litigation is required. The Sun Sentinel article added that seven homeowners in Virginia and one in Louisiana have been awarded damages, but that foreign companies may not be compelled by U.S. court rulings.

In September 2010 the New York Times reported that severe financial problems and health concerns continue to plague owners of homes where Chinese drywall was used in construction or remodeling, particularly in homes built after 2004 when Hurricane Andrew had caused U.S. made drywall to be in short supply. See"Drywall Flaws: Owners Gain Limited Relief", The New York Times. 18 Sept. 2010.

Names of Companies Producing Safe Drywall Reported Not to Have Outgassing Problems

The CPSC has listed the following companies whose drywall samples were tested to produce low or no detectable emission of sulfide outgassing.

Watch out: Notice that some of the same companies who produced problem drywall are also listed here - so just identifying the brand name of drywall does not necessarily indicate whether the specific product found in a particular home is a problem or not. That is why an expert inspection for signs of outgassing and corrosion as well as other identification steps are important.

U.S. Distributors of Outgassing Chinese Drywall

One U.S. drywall supplier, Banner Supply, was reported by Miami News Herald partner CBS4 as having been aware of the drywall outgassing problem without notifying its customers. Banner Supply switched to distributing U.S. made drywall and signed a confidentiality agreement with its Chinese supplier that obligated the distributor to remain silent about the problem. The Miami News Herald article (20 May 2010) reported that lawsuits against Banner Supply are expected to go to trial in June 2010 [in the Miami Dade Circuit Court].

Financial Aid to Pay for Chinese Drywall Repair/Replacement & Damages

Bank & Mortgage Relief for Homeowners Suffering Losses for Chinese Drywall Repairs

The U.S. government has encouraged lenders to suspend mortgage payments and to reduce property taxes on homes damaged by Chinese drywall. [Paraphrasing, The New York Times, 1 Oct. 2010]

Tax Relief for Chinese Drywall Losses in the U.S.

Insurance Coverage for Chinese Drywall Losses in the U.S.

As of September 2010, we have found no reports of payouts by U.S. insurance companies to cover costs to homeowners of repairs associated with sulphur outgassing Chinese drywall, and other media outlets indicate that insurance companies have been universally denying claims

Check this: Reported in several media outlets including the New Orleans Times Picayune (26 March 2010), The Louisiana Court Orleans Parish Judge Lloyd Medley has issued a ruling striking certain homeowners insurance policy exclusions from being relied on by Audubon Insurance (owned by AIG), a home insurance company involved in denying a Chinese Drywall claim. Audubon had excluded Chinese Drywall claims under the terms of a "pollution or contamination" exclusion that Medley concluded applies to "environmental damage" and not to damage to a building from substandard building materials. [Think of losses caused by a building collapse due to inadequate sizing of framing member - Ed.]

Lawsuit, Litigation Results for Chinese Drywall Losses

There have been some "successful" class action and individual lawsuits involving claims for damages associated with the installation of Chinese-made drywall in U.S. homes, but actual settlements that addresses the losses of all homeowners in the U.S. may be very slow in coming.

The Wall Street Journal reported on 15 October 2010 that the New Orleans Judge Fallon who is handling these cases (see below) has agreed to a settlement under which Knauf Plasterboard Tianjin and related suppliers and insurers will remove and replace Knauf drywall, wiring, copper tubing, and appliances from 300 homes in four U.S. states (Alabama, Mississippi, Louisiana, and Florida), as well as covering the relocation expenses for those homeowners. Costs are estimated at $40. to $80. per square foot of home interior space.

Appointment of the United States District Court for the Eastern District of Louisiana for Chinese Drywall Litigation Consolidated Hearings

In recognition that there has been U.S. nationwide litigation involving several class actions and thousands of individual cases, including 10 "bellwether" cases in Virginia and Louisiana, On 15 June 2009, a Judicial Panel on Multidistrict Litigation transferred all federal actions alleging damages from defective Chinese Drywall to the United States District Court for the Eastern District of Louisiana, referred to as the MDL Court) for coordinated or consolidated pretrial proceedings pursuant to 28 U.S.C. p 1407.

See In re Chinese-Manufactured Drywall Prod. Liab. Litig., 626 F. Supp. 2d 1346 (J.P.M.L. 2009) (Rec. Doc. No. 1). Above paraphrased from and also see "Case 2:09-md-02047-EEF-JCW Document 5011-1, Plaintiff's Steering Committee's Memorandum of Law in Support of its Motion to Enjoin Conflicting State Court Proceedings in Muscogee County, Georgia that interfere with this court's continuing jurisdiction over this litigation."

Bellwether Chinese Drywall Case Conclusions

Owners of seven homes in Virginia where Chinese tainted drywall was installed were awarded 2.6 million by the federal judge overseeing the Chinese drywall multidistrict litigation underway (in 2010) in New Orleans, LA as we reference just below.

UNITED STATES DISTRICT COURT EASTERN DISTRICT OF LOUISIANA, IN RE: CHINESE MANUFACTURED DRYWALL PRODUCTS LIABILITY LITIGATION, MDL NO. 2047, [PDF] Section: L, Judge Fallon, Mag. Judge Wilkinson, Findings of Fact & Conclusions of Law, Case 2:09-md-02047-EEF-JCW Document 2380 Filed 04/08/2010 [108 page PDF document]. We quote from the conclusions of that case, just below:

III. CONCLUSION

In summary, based upon the Findings of Fact and Conclusions of Law, the Court finds that scientific, economic, and practicality concerns dictate that the proper remediation for the Plaintiff-intervenors is to remove all drywall in their homes, all items which have suffered corrosion as a result of the Chinese drywall, and all items which will be materially damaged in the process of removal. Accordingly, the Court further finds that the Plaintiff-intervenors are entitled to recover damages as follows:

a. Plaintiff intervenors William and Deborah Morgan have suffered property damages, personal property damages, and other forms of compensable damages in the amount of $381,613.29. In addition, the Court finds that Plaintiff intervenors William and Deborah Morgan have suffered loss of use and enjoyment damages in the amount of $100,000.00. The Court awards Plaintiff intervenors William and Deborah Morgan total damages, caused by Taishan, in the amount of $481,613.29.

b. Plaintiff intervenors Jerry and Inez Baldwin have suffered property damages, personal property damages, and other forms of compensable damages in the amount of $341,699.11. In addition, the Court finds that Plaintiff intervenors Jerry and Inez Baldwin have suffered loss of use and enjoyment damages in the amount of $100,000.00. The Court awards Plaintiff intervenors Jerry and Inez Baldwin total damages, caused by Taishan, in the amount of $441,699.11.

c. Plaintiff intervenors Joseph and Cathy Leach have suffered property damages, personal property damages, and other forms of compensable damages in the amount of $59,676.86. In addition, the Court finds that Plaintiff intervenors Joseph and Cathy Leach have suffered loss of use and enjoyment damages in the amount of $30,000.00. The Court awards Plaintiff intervenors Joseph and Cathy Leach total damages, caused by Taishan, in the amount of $89,676.86.

d. Plaintiff intervenors Bob and Lisa Orlando have suffered property damages, personal property damages, and other forms of compensable damages in the amount of $307,905.44. In addition, the Court finds that Plaintiff intervenors Bob and Lisa Orlando have suffered loss of use and enjoyment damages in the amount of $100,000.00. The Court awards Plaintiff intervenors Bob and Lisa Orlando total damages, caused by Taishan, in the amount of $407,905.44.

e. Plaintiff intervenors J. Frederick and Vannessa Michaux have suffered property damages, personal property damages, and other forms of compensable damages in the amount of $255,607.80. In addition, the Court finds that Plaintiff intervenors J. Frederick and Vannessa Michaux have suffered loss of use and enjoyment damages in the amount of $100,000.00. The Court awards Plaintiff intervenors J. Frederick and Vanessa Michaux total damages, caused by Taishan, in the amount of $355,607.80.

f. Plaintiff intervenors Preston and Rachel McKeller have suffered property damages, personal property damages, and other forms of compensable damages in the amount of $251,741.22. In addition, the Court finds that Plaintiff intervenors Preston and Rachel McKeller have suffered loss of use and enjoyment damages in the amount of $100,000.00. The Court awards Plaintiff-intervenors Preston and Rachel McKellar total caused by Taishan, in the amount of $351,741.22.

g. Plaintiff intervenors Steven and Elizabeth Heischober have suffered property damages, personal property damages, and other forms of compensable damages in the amount of $380,886.27. In addition, the Court finds that Plaintiff intervenors Steven and Elizabeth Heischober have suffered loss of use and enjoyment damages in the amount of $100,00.00. The Court awards Plaintiff intervenors Steven and Elizabeth Heischober's total damages, caused by Taishan, in the amount of $480,886.27. In sum, the Court awards all seven Plaintiff intervenor families monetary damages for their losses caused by the defendant Taishan in the total amount of $2,609,129.99. New Orleans, Louisiana, this 8th day of April 2010.

ELDON E. FALLON UNITED STATES DISTRICT JUDGE

Additional Court Documents in re Chinese Manufactured Drywall Litigation in the U.S.

A 10 April 2008 court document reporting findings of fact and conclusions of law in GERMANO, ET AL. V. TAISHAN GYPSUM CO. LTD., ET AL., CASE NO. 09-668 [108 page PDF] specifies general scientific findings on Chinese drywall which distinguish it from typical, benign drywall as the following:

Case 2:09-md-02047-EEF-JCW Document 5011-1, Filed 08/09/10, Plaintiff's Steering Committee's Memorandum of Law in Support of its Motion to Enjoin Conflicting State Court Proceedings in Muscogee County, Georgia that interfere with this court's continuing jurisdiction over this litigation.

Case 2:09-md-02047-EEF-JCW Document 1090 Filed 09/17/10 Daubert Order motions filed by the Plaintiffs' Steering Committee and Intervenor Knauf Plasterboard Tianjin Co., Ltd., ("Knauf") to exclude specific aspects of expert witness testimony.

See: U. S. District Court, Eastern District of Louisiana (New Orleans), CIVIL DOCKET FOR CASE #: 2:09-md-02047-EEF-JCW, -EEF-JCW In Re: Chinese-Manufactured Drywall Products Liability Litigation, that collects the pertinent court documents, hosted at http://www.freecourtdockets.com/

How is Chinese drywall (the problematic product) Recognized in Homes

The U.S. CPSC and the U.S. HUD in January 2010 issued recommended interim guidance for identifying problem Chinese drywall in buildings: PROCEDURES FOR IDENTIFICATION OF HOMES WITH CORROSION FROM PROBLEM [CHINESE] DRYWALL [PDF].

The CPSC-HUD recommendations involve two basic steps in identifying Chinese drywall that may be causing or contributing to a safety, mechanical, or air quality problem in homes: [From the Executive Summary of the CPSC HUD document cited above.]

Step 1: Threshold Inspection [for Outgassing Chinese Drywall]:

Visual inspection must show:

(a) Blackening of copper electrical wiring and/or air conditioning evaporator coils; and

(b) The installation of new drywall (for new construction or renovations) between 2001 and 2008.

A positive result for this step (including both criteria) is a prerequisite to any further consideration.\

Step 2: Corroborating Evidence[for Outgassing Chinese Drywall]:

Because it is possible that corrosion of metal in homes can occur for other reasons, it is important to obtain additional corroborating evidence of problem drywall. Homes with the characteristic metal corrosion problems must also have at least 2 of these corroborating conditions if the new drywall was installed between 2005 and 2008. For installations between 2001 and 2004, at least 4 of the following conditions must be met. Collecting evidence of these corroborating conditions will in some cases require professional assessors and/or testing by analytical laboratories.

(a) Corrosive conditions in the home, demonstrated by the formation of copper sulfide on copper coupons (test strips of metal) placed in the home for a period of 2 weeks to 30 days or confirmation of the presence of sulfur in the blackening of the grounding wires and/or air conditioning coils;

(b) Confirmed markings of Chinese3 origin for drywall in the home;

(c) Strontium levels in samples of drywall core found in the home (i.e. excluding the exterior paper
surfaces) exceeding 1200 parts per million (ppm);

(d) Elemental sulfur levels in samples of drywall core found in the home exceeding 10 ppm;

(e) Elevated levels of hydrogen sulfide, carbonyl sulfide and/or carbon disulfide emitted from
samples of drywall from the home when placed in test chambers using ASTM Standard Test Method
D5504-08 or similar chamber or headspace testing4;

(f) Corrosion of copper metal to form copper sulfide when copper is placed in test chambers with
drywall samples taken from the home.

Watch out: there are many other sulphur smell sources in buildings, and some of them may be quite dangerous. We provide a detailed list of sewer and sulphur gas odor sources later in this article at SOURCES OF SULPHUR ODORS IN BUILDINGS.

Additional information is in the document PROCEDURES FOR] IDENTIFICATION OF HOMES WITH CORROSION FROM PROBLEM [CHINESE] DRYWALL [PDF] from the CPSC and HUD.

The Florida Department of Health has also provided lists and photos of components in homes likely to be affected by sulphur and other outgassing products emitted by Chinese drywall in homes. That state's DOH also provides a case definition that "... enables the user to rank homes as a possible, probable, or confirmed case. Homes that exhibit the sentinel indicators of drywall associated corrosion are defined as possible cases.  All three sentinel indicators of Criteria 1 must be met for the home to be considered as a possible case.  Criteria that define a probable or confirmed case are described in later sections." - Florida DOH

The Florida DOH describes a similar three-criteria procedure for identifying problem Chinese drywall, summarized and commented-on just below:

Criteria 1 for Possible Chinese Drywall Case Identification

  1. The home was built or renovated with drywall since 2001
  2. Observed corrosion of air conditioner evaporator coil ...
    Watch out: blackening and corrosion on copper HVAC components such as refrigerant tubing may be found in both homes with Chinese drywall and homes that did not use that material - DF.
  1. Observed metal corrosion, indicated by blackening of one or more of copper electrical wiring, exposed copper Corrosion of electrical components will presumably pertain to copper wiring and other copper electrical components exposed to air and to Chinese drywall outgassing, such as copper electrical wiring from which insulation has been stripped back - at electrical receptacles,switches, splices, and in an electrical panel; our OPINION is that depending on the level, location, and duration of corrosive gases in a building, there may be hidden damage as well, such as corrosion of internal copper parts in some circuit breakers or switches.

    Corrosion on mirrors may be recognized by loss of reflective coating on mirrors, especially at the edges and corners

The Florida DOH Criteria 2 and 3 for confirming a Chinese drywall problem case are intended for use by trained building inspection experts. We summarize below material that is provided in detail at the FL DOH Chinese drywall information web article.

Examples of Drywall Identification Stamps that are NOT Chinese Drywall

US Gypsum drywall stamp (C) Daniel Friedman US Gypsum drywall stamp (C) Daniel Friedman

Our photos (above and below) show modern identification stamps or lables that may be found drywall products used for interior walls and ceilings. Also see additional drywall identifying number stamps found at DRYWALL GYPSUM BOARD USED FOR EXTERIOR WALL SHEATHING.

US Gypsum drywall stamp (C) Daniel Friedman US Gypsum drywall stamp (C) Daniel Friedman

Criteria 2: for Probable Chinese Drywall Case Identification

  1. Observed markings on the back of drywall indicating the country of origin is China.
    Watch out: not all drywall bears identification markings; if there are no stamps on the back of drywall, also look for possible remainders of drywall top or bottom edge tapes as often that paper contains the manufacturer's identification.
    Watch out: don't assume that if you find U.S. marked drywall that no Chinese drywall is present. Some buildings were constructed or remodeled using drywall from both sources.
    Demolition, or test cuts may be necessary to expose the back or hidden side of drywall.
  1. Objective analysis of drywall in home finds Strontium levels exceed 2,000 mg/kg (ppm)
    [Details & references are provided by the Florida DOH]

If a home meets Criteria 1 for possible Chinese drywall presence, and significantly if you have ruled out other sources of hydrogen sulfide in the building, such as these sulphur or sewer gas odor sources ...

and where a number of items in Criteria 2 are confirmed, then the FL DOH considers the home a probable Chinese drywall case and investigation continues with Criteria No. 3 to attempt to identify the presence of Chinese drywall by product markings. We summarize the criteria just below:

Criteria 3: for Confirmed Chinese Drywall Case Identification

  1. Elemental sulfur presence confirmed by tests
  1. Laboratory analysis of suspect drywall headspace for reduced sulfur gas emissions
  1. Qualitative analysis of suspect drywall for its ability to cause corrosion/blackening of copper

If the results of a Chinese drywall investigation have met the criteria for “possible case”, ruled out other sources of hydrogen sulfide as significant contributors to copper corrosion in the home (we listed possible sulphur gas and odor sources just above), and receive positive results on a sufficient number of samples from one or more of the above evaluations in Criteria 3, then according to the Florida DOH, the home meets the criteria for a “confirmed case”.

Sources of Sulphur Odors in buildings Include Smells Associated with Chinese Drywall & Other Causes in buildings

Before blaming drywall for building odors, be sure that the smells are not from another detectable source such as sewer gases or a failing hot water tank anode - see ODORS, SMELLS, GASES IN BUILDINGS-DIAGNOSIS & CURE for details and see SMELL PATCH TEST to FIND ODOR SOURCE. The FL DOH suggests that reports of sulphur odors indoors are not a reliable indicator that Chinese drywall is present, because of a variety of reasons.

Below we list common sources of sulphur gases and odors in buildings as well as a few warnings about trying to confirm a Chinese drywall problem based on smell alone.

Common Sources of Sulphur Gases & Odors in buildings

In sum, before blaming drywall for building odors, be sure that the smells are not from another detectable source such as sewer gases or a failing hot water tank anode - see ODORS, SMELLS, GASES IN BUILDINGS-DIAGNOSIS & CURE for details and see SMELL PATCH TEST to FIND ODOR SOURCE. - DF

What Tests are Performed to Evaluate the Hazard from Chinese Drywall in buildings?

The following tests are commonly used to evaluate the level of indoor contamination from Chinese drywall:

EMS lab provides a range of tests for the level of outgassing and probable hazard or building damage from Chinese Drywall, as do some other U.S. environmental testing laboratories.

Remedies for Corrosive Hazardous Chinese Drywall in buildings

Unfortunately the effective remedies for the presence of problematic outgassing Chinese Drywall in buildings are likely to be extensive and costly:

Advice from AIHA, the American Industrial Hygiene Association for Dealing with Corrosive Drywall, References & Citations

Contaminated drywall imported from China has been f ound to emit sulfide vapors, impacting the air quality in tens of thousands of h omes as well as in larger buildings. In this White Paper, AIHA summarizes the available sci ence and identifies critical gaps in the current understanding of the problem that must be addressed.

The presence of corrosive drywall (CDW) can general ly be recognized based on visual inspection and the building’s construction h istory. Blackening of certain metal surfaces provides a consistent marker for the poten tial presence of CDW. Corrosion damage to electrical and mechanical systems has occ urred, and property values can be significantly diminished.

The one available medical study evaluating occupant s of homes with CDW identified short-term irritation effects possibly a ssociated with CDW emissions in subjects predisposed to irritation of the mucous me mbranes based on their medical history (e.g., asthma, dry eyes).

Federal and state response guidance and commercially available remediation services have proceeded ahead of a complete understanding of critical issues. Since emissions from CDW represent a complex, variable mix of sulfides in the parts per billion levels, setting chemical air quality standa rds is not feasible. Available air quality monitoring methods are generally not sufficiently s ensitive for either assessing exposure to CDW emissions or verifying remediation efforts.

CDW can be identified in a bulk sample analysis by a positive laboratory test for elemental sulfur. Elevated strontium content is als o a marker for potential emissions. Both elemental sulfur and strontium can be measured by laboratory analysis of drywall samples. A hand-held X-ray fluorescence meter (XRF) can be used as a field tool for identifying potential CDW locations within a struct ure.

Several attempts to control emissions while leaving CDW in place have not been successful. Air cleaning and moisture reduction, however, may reduce indoor air contaminants and corrosive effects pending removal of CDW.

To effectively control emissions from CDW, remediat ion should (a) remove all corrosive drywall; (b) eliminate visible demolition dust; (c) eliminate residual CDW odors from remaining surfaces; and (d) restore elec trical and mechanical systems to a safe, reliable, and code-compliant condition. Vario us remedial approaches have been attempted, ranging from removal of all drywall (bot h CDW and non-CDW) and all electrical and mechanical systems to selective remo val of only CDW and affected components. However, none of these strategies has b een demonstrated conclusively to eliminate emissions on a permanent basis.

Residual odors emitted by remaining surfaces have been addressed by airing the structure and its contents up to several months. Various treatments are in use to expedite this process, although none has been scientifically validated. Remediation strategies that ensure cost-effective restoration of CDW-impacted structures to pre-existing condition are needed. This is especially critical for homes where mitigation budgets are limited.

Competencies necessary for individuals assessing and remediating CDW are also discussed.

Additional work is needed to resolve CDW issues: (a ) research on underlying chemistry, emission dynamics, health risks and corr osion damage; (b) development of protocols for air quality monitoring, assessment, a nd remediation; and (c) issuance of guidance for worker protection. AIHA’s findings and recommendations will be updated as new information becomes available.

[Disclosure: the author, Daniel Friedman, is a professional member of AIHA. He does not offer field or laboratory services for CDW.]

Watch out for Bogus Chinese Drywall Remedies

Watch out:  the indoor air "purifiers" and "deodorizers" sold by some vendors who specifically advertise regarding Chinese drywall odors are not the proper approach to dealing with this problem, treating the symptom rather than the cause, and ignoring corrosion and other damage caused by this product.

Also see FTC Consumer Alert, FTC NOTICE: Defective Imported Drywall: Don’t Get Nailed by Bogus Tests and Treatments December 2009.

Reporting Chinese Drywall Complaints or "Incidents" to the US CPSC

Consumers are encouraged to report problems with their drywall, especially apparent or confirmed damage from Chinese drywall outgassing to the U.S. Consumer Product Safety Commission.

From the US CPSC / HUD 28 January 2010 HUD AND CPSC ISSUE GUIDANCE ON IDENTIFYING PROBLEM DRYWALL IN HOMES

FHA-insured families experiencing problems associated with problem drywall may be eligible for assistance to help them rehabilitate their properties. HUD’S COMMUNITY DEVELOPMENT BLOCK GRANT (CDBG) Program may also be a resource to help local communities combat the problem.

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/cgibin/drywall.aspx. Hearing- or speech-challenged individuals may access the phone number through TTY by calling the toll-free Federal Relay Service at 800-877-8339.

The US CPSC also provides a FORM for registering information about a drywall incident.

Chinese Drywall Court Cases, Litigation, Court Rulings - List of

*This Document Relates to Germano, et al. v. Taishan Gypsum Co. Ltd., et al., case no. 09-6687.*

From 2004 through 2006, the housing boom and rebuilding efforts necessitated by various hurricanes led to a shortage of construction materials, including drywall. As a result, drywall manufactured in China was brought into the United States and used in the construction and refurbishing of homes in coastal areas of the country, notably the Gulf Coast and East Coast.

Sometime after the installation of the Chinese drywall, homeowners began to complain of emissions of smelly gasses, the corrosion and blackening of metal wiring, surfaces, and objects, and the breaking down of appliances and electrical devices in their homes.

Many of these homeowners also began to complain of various physical afflictions believed to be caused by the Chinese drywall. Accordingly, these homeowners began to file suit in various state and federal courts against homebuilders, developers, installers, realtors, brokers, suppliers, importers, exporters, distributors, and manufacturers who were involved with the Chinese drywall. Because of the commonality of facts in the various cases, this litigation was designated as multidistrict litigation pursuant to 28 U.S.C. =A7 1407.

United States District Judge Fallon, of the Eastern District Court of Louisiana ruled on April 8, 2010 awarding all seven Plaintiff intervenor families monetary damages for their losses caused by the defendant Taishan in the total amount of $2,609,129.99.

Based upon the Findings of Fact and Conclusions of Law, the Court found that scientific, economic, and practicality concerns dictate that the proper remediation for the Plaintiff-intervenors is to remove all drywall in their homes, all items which have suffered corrosion as a result of the Chinese drywall, and all items which will be materially damaged in the process of removal.

The court document specifies general scientific findings on Chinese drywall which distinguish it from typical, benign drywall as the following:

  1. Chinese drywall has a significantly higher average concentration of strontium and significantly more detectable levels of elemental sulfur.
  2. Chinese drywall releases reduced sulfur gases.
  3. The sulfur gases released by Chinese drywall are irritating to the human body. Exposed individuals reported irritation of the eyes, respiratory system, and skin, among other things.
  4. The sulfur gases released by Chinese drywall cause offending odors in homes, making them hard if not impossible to live in.
  5. The sulfur gases released by Chinese drywall are corrosive to metals, particularly copper and silver.
  6. The corrosion on metals caused by the sulfur gases emitted by Chinese drywall causes premature failure of electrical & mechanical devices.
  7. The corrosion on metals caused by the sulfur gases emitted by Chinese drywall poses a fire risk

History & Properties of Gypsum & Drywall Wallboard

Drywall is a widely used construction material that is also known as gypsum board, wallboard, plasterboard, sheetrock, and gyproc. P2.0006-0003 (Cozen O’Connor, Chinese Drywall Litigation: Subrogation Whitepaper (2009)). A drywall panel is composed of a layer of hardened gypsum plaster sandwiched between two layers of paper liner. Id. Gypsum is a hydrated calcium sulfate, composed of two molecules of water (H2O) and one of calcium sulfate (CaSO4). Id.

The gypsum used to make drywall can be created both naturally and synthetically. Id. Naturally occurring gypsum is a deposit largely the result of the evaporation of water in ancient inland seas which contains large amounts of dissolved gypsum. P2.0051-001 (Treatment and Disposal of Gypsum Board Waste, Construction Dimension, February 1992 at 5).

Synthetic gypsum is chemically identical to mineral gypsum, but the amount and types of trace materials and unreacted sorbents found in the source material can vary among power plants and among mines from which it originates.
P2.0006-0003 (Cozen O’Connor, Chinese Drywall Litigation: Subrogation Whitepaper (2009)).

Synthetic gypsum is generally obtained in the final stage of industrial processes, where sulfuric acid is neutralized by a calcium salt; for example it is produced as a byproduct of coal combustion power plants. Id.; P2.0240.0014 (ASTM International report).

To make drywall from gypsum, first gypsum is crushed or ground up and heated to about 350 degrees Fahrenheit to remove approximately seventy-five percent (75%) of its water content in a process called calcining, thereafter becoming a fine white powder. P2.0006-0003 (Cozen O’Connor, Chinese Drywall Litigation: Subrogation Whitepaper (2009)); P2.0051-0001 (Treatment and Disposal of Gypsum Board Waste, Construction Dimensions, February 1992 at 5).

Second, the calcined gypsum is mixed with water, foam, and other additives to form a slurry which is fed between continuous sheets of paper on a continuous belt line. Id.

Third, as the board moves down the belt line, the calcined gypsum recrystalizes or rehydrates, reverting to its original gypsum state, and the paper sheets become firmly bonded to the rehydrated core. Id. Finally, the board is cut to length and conveyed through dryers to remove free moisture. Id.

Historically, gypsum was used as far back as 3700 B.C. by the Egyptians as a base to preserve the wall murals in the pyramids. P2.0051-0001(Treatment and Disposal of Gypsum Board Waste, Construction Dimension, February 1992 at 6); P2.0240-0022 to -0023 (ASTM International, Oct. 2009 at 9-10).

The Roman Empire used gypsum for interior purposes, such as the interior walls of Pompeii. Id.

There is little information of the use of gypsum plaster during the Middle Ages. Id. The modern science of gypsum began with the discoveries by Antoine Lavoisier outlined in his two papers on gypsum presented to the French Academy of Sciences in 1765 and 1766. P2.0240-0022 to -0023 (ASTM International, Oct. 2009 at 11). In the United States, the use of gypsum board started in the early 1950s and was driven by the following issues,

(1) avoiding the drying time of plaster which allowed earlier occupancy of buildings, and

(2) the lack of skilled plasterers in many locations. P2.0240-0026(ASTM International, Oct. 2009, pg. 13). Gypsum is fire resistant, thus making it a preferable material for drywall. P2.0051-0001 (Treatment and Disposal of Gypsum Board Waste, Construction Dimensions, February 1992 at 6).

Supporting Research on Chinese Drywall Hazards

We are aware of complaints and lawsuits related to certain wallboard manufactured in China that was imported into Florida in the 2005-2006 timeframe. All of United States Gypsum Company’s wallboard is produced in North America and does not have the problems associated with Chinese made drywall.

U.S. Gypsum also provides information about its use of synethetic gypsum as follows:

Synthetic gypsum has been used to make wallboard in the U.S. for more than 20 years: Since 2000 alone, the U.S. gypsum wallboard manufacturing industry has produced the equivalent of 72,000,000,000 square feet of wallboard made with synthetic gypsum – enough to finish the interior of more than 7,000,000 American homes. Today, all USG SHEETROCK™ brand gypsum wallboard is manufactured using either synthetic gypsum, gypsum mined in North America, or a combination of both.

Synthetic gypsum is identical to mined gypsum: Synthetic gypsum is an environmentally‐friendly product made through a controlled process by which limestone and water are used to “scrub” the emissions from coal‐fired power plants to create the end product calcium sulfate. Calcium sulfate is a high purity mineral identical in chemical composition to mined gypsum. 1 This “scrubbing” process is also called “flue gas desulfurization” (FGD).

The U.S. Environmental Protection Agency encourages the use of synthetic gypsum in making wallboard: In 1993 and again in 2000, the EPA classified synthetic, or FGD, gypsum as a non‐hazardous waste. The EPA encouraged U.S industry to use FGD gypsum to make wallboard, stating that the use is beneficial to “conserve natural resources, reduce disposal costs, and reduce the total amount of waste destined for disposal.”2 The EPA stated, “[w]e support increases in these beneficial uses, such as . . . use in construction products such as wallboard.”3 As recently as 2008, the EPA highlighted on its website a new wallboard plant that was built near a coal‐fired power plant and would use synthetic gypsum made from scrubbing the power plant’s emissions. ...

- web search 08/03/2010, original source http://www.usg.com/documents/corpcom/synthetic-gyp.pdf

  • Chinese Drywall information from the Florida state department of Environmental Protection -
    http://www.doh.state.fl.us/environment/community/indoor-air/casedefinition.html#presence - help with visual identification of Chinese drywall products.
  • Chinese Drywall References (from the FL DOH article, these documents can be obtained at www.drywallsymposium.com)
    • 1. Alessandroni, M. What's the (Elemental S)tory?). Poster Presentation at Technical Symposium on Corrosive Imported Drywall Nov 5-6, 2009.
    • 2. Demott, R., Alessandroni, M., Hayes, H., Freeman, G., Gauthier, T. - Elemental Sulfur and Trace Metal Content in Chinese and Domestic Brands). Poster Presentation at Technical Symposium on Corrosive Imported Drywall Nov 5-6, 2009.
    • 3. Salazar, R., Krause, D., Eldredge, C. - Comparison of Methods Utilized by Commercial Laboratories for Analyses of Bulk Drywall Samples. Poster Presentation at Technical Symposium on Corrosive Imported Drywall Nov 5-6, 2009.
    • 4. Singhvi, R, Lin, Y., Admassu, G., Syslo, J. Field Analysis of Elemental Sulfur in Drywall by GC/ECD. Poster Presentation at Technical Symposium on Corrosive Imported Drywall Nov 5-6, 2009.
    • 5. Spates, W., Rinicker, T., Toburen, T. - Evolution of Chinese Drywall Inspections and Findings Based on Laboratory Data and FDOH Guidelines and the Need to Incorporate New and Productive Inspection Techniques Poster Presentation at Technical Symposium on Corrosive Imported Drywall Nov 5-6, 2009.
    • 6. Tuday, M., Chen, K, Cherazaie, H., Fortune, A., Henton, W., Parnell, C, Dangazyan, M., Cornett, C. Measurement of Corrosive, Odorous and Potentially Harmful Gases from Imported and Domestic Wallboard . Oral Presentation at Technical Symposium on Corrosive Imported Drywall Nov 5-6, 2009.
    • 7. Tedder, R. Disposal Options for Imported Drywall. Oral Presentation at Technical Symposium on Corrosive Imported Drywall Nov 5-6, 2009.
    • 8. Layne, A. EPA’s Activities on Chinese Drywall. Oral Presentation at Technical Symposium on Corrosive Imported Drywall Nov 5-6, 2009.
  • Reference (Available at http://www.epa.gov/oswer/docs/chinesedrywall.pdf) (Back to top)
    • 9. US EPA Environmental Response Team Report on Drywall Sample Analysis. May 7, 2009.
  • References (Available at http://www.cpsc.gov/info/drywall) (Back to top)
    • 10. Garland, S.E., and Greene, M.A. Statistical Analysis of the Chemical Screening of a Small Sample of Unused Chinese and non-Chinese Drywall – Tab A. Oct 28, 2009.
    • 11. Interagency Task Force on Chinese Drywall October 29, 2009 Release of Initial Chinese Drywall Studies – Indoor Air Studies. Tab C. Oct 28, 2009
    • 12. EH&E Report 16512 for the CPSC. Draft Final Report on an Indoor Environmental Quality Assessment of Residences Containing Chinese Drywall – 51 home study. Nov 18, 2009.

 

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Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2019-01-14 - by (mod) -

Hi Paul, I didn't know that we shared another common interest in bikes.

D

On 2019-01-14 by Paul Probett - Incodo NZ

Hi Daniel
Hope this finds you well and like me, growing old disgracefully :) ( That's the motto of the Ulysses Motorcycle club in NZ)
We've finally run into a Chinese drywall problem on a large complex. Attached are a little collection of refs that might be of use
Regards
Paul Probett Incodo Forensic Building Pathology, New Zealand

On 2019-01-13 - by (mod) -

PCL

Ventilation with fresh air will indeed help reduce H2S levels in a building, and an air-to-air heat exchange ventilator would be a way to reduce the energy cost of the ventilation program.

However some warnings are worth keeping in mind:

1. The H2S offgassing of this drywall can cause costly, even dangerous, hidden damage to mechanical systems, such as corrosion on circuit boards or controls, as well as the better known corrosion on copper pipes etc.

2. While in an absolute sense I agree that "nothing outgasses forever" since nothing lasts literally forever, some offgassing products such as some formaldehyde flooring or wood products and some vinyl product off gassing has shown that it can continue for many years.

On 2019-01-13 by PCL

Nothing outgasses forever. For those who don't have settlement money, is it an option to simply ventilate the house enough to keep the levels of hydrogen sulfide down, and keep ventilating until they taper off? This might not be very pleasant for those in FL, but it might be more pleasant than living in a homeless shelter.

On 2016-11-19 - by (mod) -

Sewer gas, dead animal, spilled food, piping leaks. The two detectors you cite will not detect sewer gases nor other odors.

Please search InspectApedia.com for DRAIN ODORS or for SEWER GAS ODORS or for ODOR DIAGNOSIS to see how to track down and fix the trouble.

On 2016-11-19 by Barb

I am noticing a smell in my house especially under my bathroom sink but not just there. It smells almost like food? It is a somewhat heavy odor.
what could this be? We have a carbon monoxide detector and a radon gas eliminator.

On 2015-05-13 - by (mod) -

Interesting question, Rudy. I don't know an authoritative answer nor could I find one but here's an informed answer based on what we do know about Chinese Drywall hazards.

Electrical or other metallic components can be damaged by corrosive outgassing from Chinese Drywall. So electrical wiring, presumably covered with intact insulation, should not have had its copper wire cores exposed to gases and thus should be OK. But that might not be true for exposed copper wire components such as wire ends at splices or at connecting terminals of receptacles or light switches. It seems to me that an onsite inspection of such metal components is in order.

Effects of the Chinese drywall outgassing on non-metallic building components have not shown up in documents that we could find by researching the question.

On 2015-05-13 by Rudy Qualls

After removing all CDW and related dust should I remove all electrical wiring and junction and receptacle boxes, connectors? Same for ductwork for HVAC system? what about compressor setting outside and copper lead line from compressor to HVAC unit? Effects on plastic parts? Do I treat studs after pulling out CDW? Get rid of appliances? What about roof and insulation in walls and ceilings?

Question:

(Oct 16, 2012) William Tracy said:
Im a drywall installer I've been hanging sheetrock for 27 yrs I was working on Guam 90 to 95 there was this pabco sheet rock that glittered when you cut it and made us itch, and i get tiny blisters all over my right hand to mid forarm it dry's up all the skin peals off leaving raw spots on my hand it started when hanging this sheetrock and twenty yrs later it still does this once a month or so, ive asked hoards of doctors they dont know,in 97 had spots on lungs took meds for a year what was it?

doctors dont know, I know its the pabco drywall and shaftwall liner, I think it had Asbestos in it, thats just on Guam in the states I worked all over the country,and ive seen most of those id stamps you rember it because each brand of sheetrock acts differant,when you see one with a certain stamp it like not this love again,I've tryed to contact lawyers but I live in SAIPAN CNMI USA, Its hard to get things done on a tiny tiny Island in the pacific, so thats the first comment SMILE WORLD

I never knew what the smell was, never thought of if, but i know that smell as if it were cookie's baking in the oven, i had to start using a inhaler in 2001 and ive never had aszma ,ok i just checked the sheetrock i have in my house still had 8 sheets and its,Universal Gypsum Board Green Label Singapore, the reason im on this page is because of my septic tank and found this about drywall, i think this is a building code violation andwant to ck, have 2 nieghbors we all have septic tanks all 3 tanks are within 15 feet of each other know sewage comes up thru the ground,the building inspector had to pass that right?

Reply:

Thanks for the comments, Mr. Tracy.


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