Icynene's open-cell spray polyurethane foam (SPF) insulation is among the SPF industry products under scrutiny by EPA and others.
The U.S. Environmental Protection Agency (EPA) has released a new action plan for chemicals used in spray polyurethane foam (SPF) insulation. Isocyanates, such as MDI (methylene diphenyl diisocyanate), are highly reactive chemicals that can cause skin, eye, and lung irritation, asthma, and chemical sensitization when absorbed through the skin or inhaled.
When SPF is applied on a job site, both the ingredients and the byproducts of the process involve potentially toxic emissions that require protective measures for workers as well as any occupants. This is not news: worker protection protocols and quality assurance programs for SPF installation were developed by the SPF industry decades ago. Why the fuss now?
“There has been an increase in recent years in promoting the use of foams and sealants by do-it-yourself energy-conscious homeowners, and many people may now be unknowingly exposed to risks from these chemicals,” Steve Owens, assistant administrator for EPA’s Office of Chemical Safety and Pollution Prevention, told EBN. You can add to that a growing number of complaints about adverse health effects from homeowners and occupants of office buildings where SPF has been applied during energy retrofits.
EPA’s SPF action plan for MDI is being developed within its Design for the Environment (DfE) program under jurisdiction from the Toxic Substances Control Act (TSCA), which requires U.S. chemical manufacturers, importers, processors, and distributors to report to EPA any information suggesting that one of their chemicals “presents a substantial risk of injury to health or the environment.”
While the reported data is technically public information, penetrating it is very difficult, in some measure because manufacturers often claim confidentiality for proprietary components in their chemical formulations. But the cumulative evidence to date has moved EPA to take real action on this issue. The plan calls for the agency to:
issue a data call-in from manufacturers of reports they have received of significant adverse health effects (TSCA requires EPA notification but not submission of all data);
consider issuing a test rule requiring exposure monitoring studies for MDI;
consider initial rulemaking for both consumer-applied and professionally applied SPF products;
and consider identifying additional chemical substances that may be present in uncured form in consumer products.
The action plan leaves open questions about how far EPA will go to clamp down on these products, but it’s safe to think of this as a shot across the bow from EPA for the SPF industry.
In addition to the presence of MDI in the product, the chemical reaction and curing of SPF can produce other chemicals of concern: excess isocyanates, aldehydes, amine catalysts, and other volatile organic compounds. We don’t know much about the nature and quantities of offgassing of these substances, the curing rates of SPF, or how health risks can change with improper environmental conditions or mixing ratios during the SPF process. To that end, there is a new ASTM standard under development. John Sebrowski, a senior associate scientist with Bayer MaterialScience and chair of the task group working on this ASTM standard, is helping develop a standard practice to establish re-occupancy times after onsite SPF application. “We are currently getting ready to conduct research using micro-scale chambers and thermal desorption techniques to measure emissions,” he told EBN.
When asked what relationship the current ASTM draft standard and research might have to the existing protocol offered by Bayer MaterialScience (which recommends re-occupancy times of 12 hours and 24 hours for workers and occupants, respectively), Sebrowski responded that the protocol would be used as a starting point, but “we are also investigating other approaches to measuring the emissions.”
According to EPA, safe re-entry times put forward by manufacturers vary between 8–24 hours for one-component SPF and 23–72 hours for two-component SPF. But more research and standardized testing is clearly needed. EPA is not working alone on this issue; several other federal agencies—including the National Institute for Occupational Safety and Health, the Occupational Safety and Health Administration, and the Consumer Product Safety Commission—are part of the team. Each is concerned about protecting workers or consumers from health effects from the increasingly prevalent site-applied SPF.
“I think you have to be careful when you discuss the toxicity of spray foam,” says David Price, environmental scientist in the indoor environment division of EPA’s Office of Air and Radiation. “I have not seen any information at this point that there is any hazard to occupants.” While Price supports EPA’s decision to gather data on possible post-occupancy issues with SPF, he doesn’t want the public to “find the accused guilty before you hear the case.” Price has seen some of the anecdotal evidence as well as some of the scientific findings, and says that no cause-effect relationship has yet been found between SPF installation and post-occupancy illnesses. “It’s appropriate for EPA to look at this stuff; that’s what we do,” Price told EBN. “But I’m very sensitive about tagging a product as ‘of concern’ or ‘may be toxic’” before the data has been gathered and reviewed.
EBN contacted several builders and foam industry professionals, and found that most were unwilling to be quoted on an issue they deemed sensitive and still-unfolding. One leading green remodeler offered this perspective: “I have stopped using SPF in any of my projects at this point. I simply can’t and won’t jeopardize my clients’ health and the reputation of my company by using building materials with the emissions profile of SPF.”
SPF has unique advantages that can be difficult to replace. If you decide to continue using it while EPA continues its work, here are some recommendations.
Make sure that your SPF contractor installs SPF correctly, employing quality control/assurance protocols such as the following the Spray Foam Quality Control – Canadian Installation Requirements, or the ABAA Quality Assurance program.
Follow current EPA recommendations on a safe approach to installation, from the publication Quick Safety Tips for SPF Users.
If you are a homeowner or building manager or employee in a building in which SPF will be installed, follow EPA’s Steps to Control Exposure.
Also, stay tuned to
; the SPF industry is working on a new class of
polyurethanes (HPINUs)—that may pose much less serious occupant and worker health issues than our current slate of SPF building products.