ERI Analytical Services

Analytical Services

ERI was among the very first analytical laboratories licensed by the Texas Department of Health (now Texas Department of State Health Services), in 1992. The laboratory, which already held National Voluntary Laboratory Accreditation Program, holds the highest accreditations for the analysis of asbestos in:

Polarized Light Microscopy (PLM)

PLM is the preferred method of analyzing for asbestos content in bulk materials. The majority of bulk materials analyzed in our lab by PLM are building materials collected from public buildings, commercial structures, industrial facilities, and residential dwelling units.

The methods (lnterim Method for the Determination of Asbestos in Bulk Insulation Samples, 40 CFR Part 763, Subpart E, Appendix E & ISO/1EC 17025:2017 revised 2020) call for the separation and quantification of the fibrous component of the material under l00X magnification. The fibers are then treated and viewed under polarized light to evaluate the unique characteristics of asbestos fibers.

Phase Contrast Microscopy (PCM) for Asbestos

PCM is the most widely accepted method of determining airborne fiber concentrations. Air samples are typically collected on 25mm non-conductive cassettes with 0.8 multiple cellulose ester filters using air pumps at flow rates between 2-20 liters per minute.

The filters are removed from the cassettes at the lab, placed on glass slides, prepared, and analyzed at 400X magnification. Samples are analyzed using the National Institute of Occupational Safety & Health (NIOSH) 7400 method. This method counts fibers 5 microns or larger, and which have a 3:1 length to width ratio. The 7400 method does not differentiate between fiber type - all fibers are counted.

Phase Contrast Microscopy (PCM) for Mold

PCM is also the most widely accepted method of determining airborne mold spore concentrations. Air samples are typically collected on 37 mm cassettes with an adhesive cover slip, using air pumps at approximately 15 liters per minute. The adhesive cover slips are removed from the cassettes at the lab, placed on glass slides, covered with a cover slip, and analyzed at l000X magnification. Identification of spores to the genus is then performed.

All ERI lab staff, and field technicians operating field labs, participate in an extensive Quality Assurance/Quality Control program, including the American Industrial Hygiene Association (AIHA) Proficiency Analytical Testing (PAT) Program.

PCM for Mold & Asbestos