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Asbestos Fiber Analysis LAP


The image shows a 1866 Standard Heated Crocidolite to 498 degrees C between 1866 Standard Amosite in 1.68 Crossed Polars with Red Plate 530 nm (z). 

Credit: ALSF

The NVLAP Asbestos Fiber Analysis program provides assurance that laboratories are competent to analyze asbestos samples using polarized light microscopy (PLM) and/or transmission electron microscopy (TEM). The Asbestos Hazard Emergency Response Act (AHERA), enacted in 1986, requires that laboratories that analyze asbestos samples taken from public, or private, elementary or secondary schools, to be accredited by the National Institute of Standards and Technology (NIST) National Voluntary Laboratory Accreditation Program (NVLAP).

Requirements Documents

Overall Program: 

Bulk (PLM):

Airborne (TEM):


Proficiency Testing Requirements

The Asbestos Fiber Analysis LAP requires laboratory participation in a NVLAP-mandated proficiency testing program provided by RTI International (RTI), The requirements for laboratory participation in NVLAP-mandated proficiency testing are given in NIST Handbooks 150-3 and 150-13. Proficiency testing is conducted biannually (twice a year) for PLM and annually (once a year) for TEM testing laboratories. For applicant labs, proficiency testing must be completed before the initial assessment.

The proficiency testing contacts at RTI are J. Todd Ennis (jte [at] (jte[at]rti[dot]org)) for PLM and Sara Harrison (seharrison [at] (seharrison[at]rti[dot]org)) for TEM.


References and Information

Bulk (PLM):

Airborne (TEM):

Related Links:




Created July 24, 2013, Updated April 23, 2024