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If vermiculite insulation bulk samples analyzed by standard polarized-light microscopy (PLM) analysis is found to be less than 1% asbestos is it still considered an asbestos-containing material under the Asbestos Hazard Emergency Response Act (AHERA)?

Vermiculite insulation containing less than 1 percent asbestos does not qualify as asbestos containing material (ACM) under AHERA and the asbestos-containing materials in schools rule. If standard PLM analysis, ensuring that bulk samples comply with sampling requirements as laid out in 40 CFR part 763.86 and that subsequent analysis of such samples complies with analysis requirements set forth in 40 CFR part 763.87, concludes that a material contains less than 1 percent asbestos, then it is not ACM. As the Environmental Protection Agency (EPA) has recommended in its guidance to homeowners the school may wish to treat the vermiculite insulation as containing asbestos before taking any actions that might disturb it.