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If friable asbestos-containing material (ACM) is accidentally left behind after an abatement project had passed air clearance by transmission electron microscopy (TEM) analysis, do I need to re-test the air?

Yes. Both the visual inspection and the abatement were not properly completed under 40 CFR part 763.90(i)(1). The loose debris should be removed and the area thoroughly re-cleaned. Air monitoring should be repeated using TEM analysis for the functional space where the original abatement occurred. (40 CFR part 763.90(f) and (i))