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The Occupational Safety and Health Administration (OSHA) recently issued its Final Rule on confined spaces – 29 C.F.R. Part 1926 Subpart AA. “Confined spaces” include any space large enough for a worker to enter it. The scope of the regulation, therefore, includes crawl spaces and attics.
OSHA has issued a fact sheet specifically on crawl spaces and attics. In that fact sheet, OSHA specifically cautions about installation of spray foam insulation:
“Crawl spaces and attics can be both confined spaces and permit-required confined spaces under the new standard. For instance, working in an attic and applying a large amount of spray foam (or another chemical) in a short period of time can expose a worker to low oxygen levels or a hazardous atmosphere.”
The fact sheet also notes that inadequate attic ventilation resulted in a flash fire, killing a spray foam installer.
Your choice of insulation has health and safety implications. To learn more, check out our health and safety page.