EndPoint personnel have been conducting 3-Year Re-inspections of schools in accordance with the Environmental Protection Agency (EPA) Asbestos Hazard Abatement Response Act (AHERA) on behalf of a number of municipalities in New Hampshire and Massachusetts.  As part of the re-inspections, EndPoint personnel review previous AHERA Inspection Reports, some of which contain suspect asbestos-containing building material (ACBM) sample results that used polarized light microscopy (PLM) analysis.

It has been documented that PLM analysis can produce false negative results for asbestos in vermiculite insulation.  During a recent AHERA building inspection, the 1988 initial AHERA inspection document was reviewed and vermiculite was identified as an analytical result for the PLM analysis of a cementitious material.  Bulk samples collected by EndPoint detected trace (less than one percent) asbestos in the material likely due to the vermiculite.  Although the material was not determined to be an ACBM, there are still regulatory requirements for materials that contain less than one percent asbestos that OSHA requires for worker safety for any renovation or demolition project.  As a result, there may be many of these initial AHERA reports within the various municipalities that have documented the detection of vermiculite during PLM analyses but no follow up has been taken to determine if the material contains asbestos.  A review of those initial AHERA documents is warranted to ensure that the amount of asbestos present in the school is not underestimated.  In addition, if vermiculite tested materials are not determined to be an ACBM, but do contain asbestos less than one percent, they need to be documented to as such for any potential future renovations or demolition projects.