Welcome to IAAI’s January 2010 CFITrainer.Net Podcast. During this month’s podcast, we’ll look at preliminary research on corrosion caused by Chinese drywall, a new database focused on fires in historic buildings, a warning on blown-in insulation, and the launch of the new firearson.com web site. Let’s get started.
Our main story this month is research into the potential corrosive effects of Chinese drywall. The devastating hurricanes of 2004 and 2005 were a main driver behind a construction boom in 2006 and 2007. Many of the homes built in this period, especially in the humid Southern United States, used Chinese drywall in their construction. The Consumer Product Safety Commission has received over 2,800 reports of a variety of poor health symptoms and the corrosion of metal components in homes that have Chinese drywall.
As a result of these complaints, the CPSC has undertaken an investigation of Chinese drywall to determine if it is the cause of these health complaints and metal corrosion. The research has three components: evaluation of the relationship between the drywall and the reported health symptoms; evaluation of the relationship between the drywall and electrical and fire safety issues in the home; and the tracing of the origin and distribution of the drywall. The concern is that moisture combined with the chemicals found in the Chinese drywall are corroding the metal parts of the home, causing electrical hazards and compromising the integrity of fire safety equipment.
In November 2009, the CPSC released preliminary findings on its research into the electrical and fire safety issues possibly created by Chinese drywall. The research into possible electrical issues has found a strong association between the problem drywall, the hydrogen sulfide levels in homes with that drywall, and corrosion in these homes. A preliminary visual inspection by CPSC Electrical Engineering staff on all of the harvested electrical components in the tested homes revealed substantial corrosion of copper wiring, but there were no indications of significant overheating of conductors or conductive parts due to the corrosion. Elemental analyses of both forms of corrosion indicated the presence of copper, sulfur, and small amounts of oxygen, which strongly suggested the presence of copper sulfide and copper oxide. A number of severely corroded receptacles were examined and the wires attached to these receptacles showed several morphologies of copper corrosion products including cauliflower-shaped nodules and spongiform texture. The corrosion nodules were readily found on the surface of the exposed copper wires, while the spongiform texture appeared in micro-cavities beneath the corrosion nodules. The overall thickness of the corrosion layer varied from almost zero to twenty micrometers. Corrosion of copper wiring is most extensive where bare copper was exposed. Intact electrical insulation on copper wiring appeared to protect the underlying copper conductor from corrosion.
In the fire safety components portion of the preliminary research findings, an initial examination of copper natural gas supply tubing and air conditioner heat exchanger coils found a thin black layer of copper sulfide on all of the copper samples examined. Corrosion products were also observed on other types of metals in the air conditioning coils in the areas where condensation would frequently make the metals wet. None of the samples examined were failed components and no evidence of an imminent failure was found on any of the samples. All of the corrosion damage observed was consistent with a general attack form of corrosion that progresses in a uniform manner. The sample size is currently too small to draw conclusions on whether or not this corrosion may cause a failure.
Ongoing laboratory tests continue to investigate the nexus between safety and the short and long-term effects of such corrosion. Updates can be found at cpsc.gov/info/drywall.
In other news, English Heritage has created FReD, or Fred, the Fire Research Database, on behalf of Great Britian’s Historic Buildings Fire Research Coordinating Committee to foster the sharing of unpublished knowledge about fires in historic buildings and to encourage the development of joint research to improve the protection of historic buildings from the effects of fire. The database includes buildings from many countries, not just Britain. The database of projects, research reports, and other documents covering many aspects of fire and fire investigations in historic buildings can be searched online at fred.english-heritage.org.uk.
A recent series of 55 fires in Melbourne, Australia has thrown a light on improper installation of blown-in insulation as a fire cause. Companies were inducing consumers to take advantage of a national rebate program using door-to-door sales techniques, but, unfortunately, installers provided by these companies were not properly trained in how to install the blown-in insulation. Like many home contracting services, when blown-insulation is not properly installed around electrical fixtures, overheating, fault, and fire can result. Fire investigators should remember to always consider whether improper installation could have been a fire’s cause.
Finally, we close with news from IAAI.
The IAAI Board of Directors of the International Association voted unanimously to formally endorse the Bomb Arson Tracking System or (BATS) as a vital tool for professionals who work in the field of fire, arson, and explosives investigation. BATS is a web-based repository of information on bombing, explosives and arson incidents. Fire investigators have 24/7 access to the database and the ability to share information with other fire investigators in the course of their investigations. BATS also facilitates trend analysis and incident comparison to identify potential perpetrators. IAAI is urging all professional fire and arson investigators and their agencies to use BATS as a tool to participate in providing incident information that will assist other investigators and agencies as they conduct the investigation of bombing, explosive, and arson incidents. BATS is available at bats.gov.
Also in IAAI news, the new firearson.com web site debuted this month. The site has been expanded considerably and features a new graphic look and easy navigation. Highlights of the new firearson.com site include:
- Easy online membership purchase and membership renewal
- A continuously updated news feed of fire-related articles
- A compendium of all IAAI’s professional development opportunities
- A simplified training calendar format with expanded course information
- A new section devoted to Chapter activities
- Complete corporate and staff information about IAAI
More features will be added to the site in the coming months, including merchandise for purchase, an archive of IAAI publications, a newsroom and press releases. Check back often as the new site grows.
That concludes this IAAI CFITrainer.Net podcast. We’ll see you again next month.