spray polyurethane foam

The Dangers of
spray polyurethane foam

Spray polyurethane foam (SPF) insulation has become increasingly popular in both residential and commercial applications in an effort to reduce heating costs and decrease consumption of fossil fuels. Not only is SPF said to be more energy efficient than traditional fiberglass insulation, it is typically cheaper to purchase and install. Most SPF manufacturers claim that their product is “environmentally friendly” or “green”; however, there are no regulatory authorities that have evaluated and substantiated these claims.

The Basics

When professional applicators follow appropriate safety measures, the potential hazards associated with SPF chemicals can be effectively managed. However, if risks are improperly managed, workers and building occupants could be exposed to potential hazards present in aerosol mists and vapors. In addition to the release of airborne SPF chemicals during spray application, certain components may emit from newly installed SPF insulation products for a period of time following installation.

Applying spray polyurethane foam

Improper installation is often the cause for symptomatic reactions to SPF although some people have had adverse reactions with very limited exposure to the chemicals commonly found in SPF. Manufacturers assert that the chemicals used in spray foam are supposed to lose toxicity once it is sprayed inside homes, but other research indicates that the foam releases formaldehyde gas and other toxic substances even after it is installed.

Workman’s comp claims have also been on the rise from spray foam installers who have become ill as a result of repeated exposure to the chemicals in the foam. William Swietlik, co-chair of the EPA’s workshop on spray foam dangers, has asserted that the chemicals used in the insulation are “a leading cause of workplace asthma and are a well-known sensitizing toxicant to humans.”

The bottom line: be sure to research your installer, their safety protocols, and reviews. SPF has been effective for reducing heating and cooling costs; however the risks with improper installation and exposure to the compounds at any time during the process may outweigh the benefits.


“Curing” of SPF means that the chemicals in the product are reacting to produce polyurethane foam. SPF material is highly adhesive and will stick to most surfaces. SPF may appear hardened or “tack-free” within a range of a few seconds to a few minutes after application.  However, at this stage, the foam is still curing and still contains unreacted SPF chemicals.

Some manufacturers recommend 24 hours after application for the two-component high pressure “professional” SPF system for worker re-entry without the use of PPE and for re-occupancy by residents and other building occupants, but the recommended time may vary.

Contact your manufacturer or supplier for specific guidance on ventilation time, re-entry time, and re-occupancy time for your specific product and scenario.

Residential applications:
  • air barrier
  • attics
  • exterior subgrade
  • perimeter walls
  • interior Insulation
Spray Polyurethane Foam Insulation
Symptoms of exposure:
  • wheezing
  • shortness of breath
  • coughing
  • irritation of the eyes and lungs
  • fever
  • stuffy nose
  • sore throat
  • tightness in the chest
  • headaches
  • joint pain


The potential for off-gassing of volatile chemicals from spray polyurethane foam is not fully understood and is an area where more research is needed. Standardized methods are needed to assess the potential impacts of SPF insulation products on indoor air quality and to establish re-entry or re-occupancy times after product installation in a building and to better understand post-occupancy ventilation needs, such as through HVAC considerations during the planning phases before SPF or other insulation is installed. Remember, insulation is intended to seal a residence and can significantly decrease air exchanges, emissions from SPF and other products, including combustion sources, can build up in a building.

Need help?


The well-being of our employees, our customers, our communities, and our environment is at the heart of our business here at Prism Analytical Technologies (Home Air Check's Laboratory). Now, more than ever, we must come together as we adjust to the challenges resulting from the coronavirus disease (COVID-19). I am reaching out to let you know that we at Prism Analytical are committed to operating in a safe and responsible manner while maintaining the highest standards of quality in these troubled times.   

Prism Analytical continues to follow the direction of federal, state, and local governments regarding our operations, and we are closely monitoring the latest reports from the CDC and WHO.  We have instituted recommended cleaning and disinfection procedures of all our sampling equipment as well as the work spaces of all our personnel. We have also enabled staff to work from home where possible, delayed or cancelled upcoming travel plans, and are restricting access to our work spaces.

Our business will continue to operate as usual; from shipping equipment to laboratory operations to reporting. As always, we are here to help you be successful and are available via phone and email to help you plan projects, review data and answer questions.  

This is a constantly evolving situation and we will continue to closely monitor conditions and evaluate additional measures to support our customers, team members, and communities as needed. We will provide prompt updates regarding any adjustments to our procedures or operations.

We sincerely appreciate your patience during this time and are committed to maintaining transparent and open communication with you. Please reach out to me or any of our staff if you have any questions or concerns.

As a reminder, as more people spend time at home it’s more important than ever that they maintain good indoor air quality to help keep everyone healthy and facilitate successful remote learning and working.

Privacy Preferences
When you visit our website, it may store information through your browser from specific services, usually in form of cookies. Here you can change your privacy preferences. Please note that blocking some types of cookies may impact your experience on our website and the services we offer.