24 Oct Winter Warm-Ups Update
A word of warning about spray polyurethane foam insulation
Winter is coming again, and so are all of the e-newsletters about insulation, weatherization tips and and energy savings. Spray polyurethane foam (SPF) is big this year because it stops air flow — around that water pipe or that vent through the roof — when other insulations don’t.
But the companies pushing their SPFs aren’t really talking about what the chemicals in these products can do if not handled properly. And if you’re chemically sensitive, you might not want to use them at all.
SPFs are a very effective insulation product, and they are on our standing weatherization tip list. But, whether open- or closed-cell, SPFs contain diisocyanates, amine catalysts, flame retardants, polyol oils and blowing agents. Without getting into all of these, diisocyanates cause asthma, lung damage and can sensitize humans, triggering ongoing reactions to chemicals.
The primary hazard exists when the products are being applied, and unsafe levels of the chemicals are released into the indoor air. The label on your product might not say it, but NIOSH and OSHA would tell you to wear full protective equipment, including a fresh-air- supplied respirator. In the array of information available online, you will also see that unprotected workers and building occupants should leave the building while spraying is underway, and they should not come back until all dust and vapor are ventilated out of the building, and just when that is can be difficult to determine.
Although the Environmental Protection Agency (EPA) is relatively certain that chemical off-gassing at unsafe levels is unlikely after the product is dry and enclosed, this remains a source of study and investigation.
— Nancy Kibbee is editor at naturalinteriors.com