Health and Safety of Spray Foam Insulation
Spray foam insulation, or SPF, has been used regularly in both residential and commercial buildings since the 1970s, so we now have more than thirty years of performance data and scientific testing to analyze when determining the health and safety of this material. As a result, experts agree spray foam is safe and chemically inert if it is:
- Properly applied
- Once fully cured
Proper Spray Foam Application
With spray foam—as with many engineered construction materials—it’s important to do your research, find a reputable manufacturer and products, and use only a qualified, trained, and certified applicator. An experienced professional knows how to take the right precautions so the installation process is safe, done properly, and the spray foam cures thoroughly before anyone without PPE inhabits the space.
Spray foam—more formally called spray polyurethane foam (SPF)—contains isocyanates, which are released during the exothermic reaction stage of application. Isocyanates have a low level of toxicity until the curing process is fully complete. Improper exposure to isocyanates can cause irritation to the eyes, gastrointestinal tract and respiratory tract. Direct skin contact can cause inflammation, and long-term exposure can cause asthma.
For these reasons, spray foam installers and other workers in the area during spray foam installation must wear the proper personalized protective equipment (PPE):
- NIOSH-approved full-mask, or air purifiying respiratory protection
- Chemical resistant disposable protective coverall with hood that ensures no skin is exposed
- If working with chemicals and there is a chance they may be splashed wear impermeable protective clothing (e.g., PVC, polyethylene)
- Fabric gloves fully coated with nitrile, neoprene, butyl, or PVC. Or cotton gloves over nitrile gloves may be used
- Disposable over-boots with skid-resistant soles
- Chemical resistant eye and skin protection
In addition, the workspace must be properly ventilated.
Choose Your Product Carefully
A high-quality spray foam brand will provide explicit technical instructions on how to apply and the curing time and process of their products. The curing process is unique to each specific brand, so the applicator should never deviate from the manufacturer’s specific recommendations and technical data. In addition, there can be deviations in the curing process in varying environments, depending on factors like humidity level and temperature. It is best to err on the side of too long instead of too short a time.
As a general estimate, the curing process usually takes from 24-72 hours, during which time SPF’s exothermic reaction is occurring, and proper ventilation, PPE, and safety precautions are mandatory. During this curing time, the space is uninhabitable.
It bears repeating that spray foam is not a D.I.Y. product. It should only be applied by qualified, trained, and certified applicators familiar with the brand they are applying. If application is done improperly or by an inexperienced applicator, too much SPF foam could result in uncured particles that linger beyond the normal curing time. In this situation, the uncured particles would continue to release gas and cause the space to be uninhabitable until remediated. Untrained applicators may also begin trimming/shaving before the foam is full cured gases will be released while exothermic reaction is still in process.
Trained applicators never vary the manufacturer’s suggested curing time. No human contact or habitation of the space is allowed before curing is complete. We strongly recommend choosing only trained and certified contractors to apply spray foam insulation.
SPF doesn’t contain ozone-depleting substances, and once it’s fully cured, it does not release toxic gases or leach harmful chemicals. With proper application by a qualified professional, spray foam is safe and can actually contribute to the “health” of a building by helping to prevent mold growth and contributing to the air quality of the building over its lifetime.