Hygeia Laboratories Inc.

 
Polarized Light Microscopy (PLM)
The Environmental Protection Agency (EPA) defines Asbestos Containing Materials (ACM) as any material containing asbestos in quantities greater than one percent.  Hygeia uses PLM analysis to identify and quantify the percentage of asbestos in bulk materials.  Typically, PLM is performed in accordance with procedures established in December, 1982 by the EPA Interim Method for the Determination of Asbestos in Bulk Insulation Samples (EPA-600/M4-82-020) as outlined in 40 CFR 763.109 Appendix A, Subpart F.  Hygeia also follows the modifications and improvements made to this method in the EPA Method (EPA/600/R-93/116) "Method for the Determination of Asbestos in Bulk Building Materials."  These methods are intended to quantify asbestos in amounts ranging from less than one percent to one hundred percent.

Phase Contrast Microscopy (PCM)
It is the policy of Hygeia to measure the concentration of airborne fibers using PCM in accordance with the NIOSH 7400 Method.  When this procedure is used for assessing personal exposures, the methodology for analyzing air samples complies with OSHA's ORM in Appendix A of 29 CFR 1910.1001. 

Transmission Electron Microscopy
TEM analysis of asbestos abatement clearance samples is conducted to comply with the Asbestos Hazard Emergency Response Act (AHERA).  Air sample preparation and analysis is performed as specified in the EPA Final Rule and Notice of October 30, 1987, 40 CFR Part 763 - Appendix A to Subpart E.  Asbestos Structures are identified using morphology, Selected Area Electron Diffraction (SAED) and Energy Dispersive Spectroscopy (EDS) X-Ray microanalysis.

TEM analysis of air samples for screening purposes is performed using EPA Method 68-02-3266, Level I.  Fibrous structures (fibers, bundles, clusters and matrices) are counted, sized, and identified as to asbestos type (chrysotile, amphibole, ambiguous, or no identity) by morphology and by visual SAED pattern recognition.

TEM analysis of air samples for regulatory action is performed using EPA Method 68-02-3266, Level II.  Fibrous structures are counted, sized, and identified as to asbestos type by morphology, visual SAED pattern recognition, and elemental analysis using EDS X-Ray microanalysis.

TEM analysis of air samples for confirmatory analysis of controversial samples is performed using EPA Method 68-02-3266, Level III. Fibrous structures are counted, sized, and identified as to asbestos type by morphology, applying quantitative SAED to a selected number of micrographs, and elemental analysis using EDS X-Ray microanalysis.

TEM analysis of bulk materials is conducted by one of the following in-house methods:

Qualitative analysis is performed to confirm the presence of asbestos (drop-mount technique).

Semi-quantitative analysis is performed using an in-house method based on the Chatfield Method (SOP-1988-02 Rev.1 as presented to the American Society for Testing and Materials [ASTM] Committee).  This method, which is best suited for organically-bound construction materials such resilient floor tiles, allows the estimation of the concentration of asbestos expressed as weight percent of the original sample.  The concentration of asbestos is estimated and the type of asbestos present is identified from the residual material left after the reduction of the sample matrix using gravimetric sample preparation techniques, mainly, ashing and acid dissolution.  Depending on the efficacy of the gravimetric sample reduction, the limit of detection for this method is typically around 1 percent.

Full-quantitative analysis is performed using an in-house method based on EPA/600/R-92/116 July 1993, Section 2.5.5.2, Analytical Electron Microscopy.  This method is used to quantify weight percent of asbestos in bulk materials including soil and sludge samples.  Fibrous structures are counted, sized and identified as to asbestos type by morphology, visual SAED pattern recognition and elemental analysis using EDS X-ray microanalysis.  The concentration of asbestos is calculated from total mass of asbestos structures, volume of aliquot filtered, weight of the bulk sample used, and the area analyzed.  The limit of detection for this method is typically less than 0.1%.

TEM analysis of vacuum, or dust samples, is performed in accordance with the ASTM Standard Test Method for Microvacuum Sampling and Indirect Analysis of Dust by Transmission Electron Microscopy for Asbestos Structures Number Concentrations (D5755).  Fibrous structures are identified by morphology, visual SAED pattern recognition, and elemental analysis using EDS X-Ray microanalysis.

TEM analysis of non-potable water samples is conducted in accordance with EPA/600/4-83-043 (Method 100.1), Analytical Method for Determination of Asbestos Fibers in Water.  Fibrous structures are counted, sized and identified as to asbestos type by morphology, by visual SAED pattern recognition, and by elemental analysis using EDS X-ray microanalysis.

TEM analysis of drinking (potable) water samples is conducted in accordance with EPA/600/R-94/134 (Method 100.2) Determination of Asbestos Structures over 10 micrometer in length in Drinking water.  Fibrous structures over 10 micrometers in length are counted, sized and identified as to asbestos type by morphology, by visual SAED pattern recognition and by elemental analysis using EDS X-ray microanalysis.