- (a) Clearance air samples shall be submitted for analysis to a laboratory that uses phase contrast microscopy (PCM) for the analysis of air samples for asbestos content unless accredited by the NIST for TEM, in which case the laboratory may analyze air samples using TEM.
- (b) Analytical procedures for PCM shall be in accordance with NIOSH Method 7400, Issue 3, entitled “Fibers” published in the NIOSH Manual of Analytical Methods, 5th Edition, June 14, 2019, available as noted in Appendix B. Air volumes sampled shall be sufficient to accurately determine, to a 95 percent probability, fiber concentrations of 0.01 fibers/cubic centimeters of air (f/cc).
- (c) Analytical procedures for TEM shall be as stated in 40 CFR Part 763, subpart E, appendix A: “Mandatory and Non-Mandatory” or as defined and accepted by the NIST for TEM accreditation.
- (d) Analytical procedures for PLM shall be as stated in 40 CFR Part 763, subpart E, appendix E: “Interim Method of the Determination of Asbestos in Bulk Insulation Samples” or as defined and accepted by the NIST for PLM accreditation.
Source. (See Revision Note #1, Revision Note #2, and Revision Note #3 at chapter heading for Env-A 1800) #14104, eff 11-1-24, EXPIRES: 11-1-34