What analysis method should be used for asbestos content analysis by PLM under AHERA?

The correct method for asbestos content analysis by Polarized Light Microscopy (PLM) under the Asbestos Hazard Emergency Response Act (AHERA) is the interim method for the determination of asbestos in bulk insulation samples. This method is specified within AHERA regulations and is designed to ensure accuracy and consistency when analyzing bulk samples suspected of containing asbestos.

PLM is particularly effective for identifying and quantifying asbestos fibers in materials, and the interim method provides a structured approach for handling these samples, including preparation, mounting, and the actual microscopy analysis. This ensures that laboratories can produce reliable results, which are critical for assessing the presence of asbestos in insulation and other building materials.

The other methods mentioned, such as the standard method for bulk analysis from the EPA and field analysis techniques, may not align specifically with AHERA's requirement for analysis in bulk insulation samples. Similarly, visual inspection techniques are useful for identifying potential asbestos-containing materials but do not provide the quantitative analysis required for compliance with AHERA regulations.