What We Do
Alliance Analytical Laboratories analyzes “fibers in air”, using National Institute of Occupational Safety and Health (NIOSH) Method 7400, entitled “Asbestos and Other Fibers by PCM“. At the project site, a 25 mm cassette, loaded with a mixed cellulose ester filter with .8 micron pores is placed inline on a small battery powered or 110 volt vacuum pump. Once the flow rate is calibrated and recorded, air is drawn over the filter membrane for a period of time.
The cassette is received here at the laboratory via Chain-of-Custody and the analysis is performed by first removing the filter membrane from the cassette housing and “clearing” the cellulose using vaporized acetone. Once cleared, any contaminates caught on the filter can be viewed under a specially equipped 400x microscope. Any fiber longer than 5 microns with a 3/1 aspect ratio is counted. When either 100 fibers, or 100 locations on the microscope slide are counted, a calculation is made and results are reported in “fibers/cc”.
Additionally, through our affiliated company, Envision Environmental Solutions. LLC (www.envenvsol.com) we are able to go “on-site” and collect the air samples and\or bulk material samples for you, whether it be a pre-demolition\renovation building materials inspection, OSHA personnel sample collection, daily work area samples or final visual clearance and air sample collection\analysis.
What We Do Really Well
Alliance Analytical Laboratories has an advantage over other laboratories that analyze for fibers using NIOSH method. Many laboratories can accurately count fibers and provide written reports. Our experience in Industrial Hygiene helps us to realize that while accuracy and reporting are important, when it comes to OSHA Personnel Samples, it’s important to take the extra step, and report the TIME WEIGHTED AVERAGE (TWA) results. By employing our OSHA SAMPLE DATA CHAIN OF CUSTODY data input form, removal contractors can provide the information necessary to receive their PERSONNEL SAMPLE RESULTS with the TWA already calculated. Additionally, information provided by the removal contractor can be incorporated into the SAMPLE DATA REPORT COVER PAGE, and used to develop OSHA required INITIAL EXPOSURE ASSESSMENTS and NEGATIVE EXPOSURE ASSESSMENTS.
A Bit About Asbestos
Asbestos is a “generic” name for six naturally occurring minerals. The “mineral” names are Chrysotile, Grunerite (Amosite), Tremolite, Actinolite, Anthopholite and Crocidolite. Asbestos is mined in “Open Pit” mines primarily in Canada, United States, Africa, and Australia.
Asbestos, once mined is milled can then be added to many products. The Environmental Protection Agency (EPA) has estimated that asbestos has been incorporated into approximately 3000 building products. Many of these building products have found their way into homes, schools, college campuses, sports auditoriums and manufacturing processes. In short, it has been used in all the places we live, work and play.
Determining Asbestos Content in Building Materials
To determine whether a material contains asbestos, a small sample of the material (Bulk Sample) is obtained. In a public or commercial building, public or private school, grades K-12 the sample collector must be accredited as a Building Inspector as defined in the Asbestos Hazard Emergency Response Act , Part 763.85. Once received by the laboratory, the sampled material may be subjected to “ashing”, or acid treatments to remove organic content that may block the analyst from seeing the asbestos content.
Any asbestos material present can then be viewed and identified using a Polarized Light Microscope (PLM). The asbestos type is determined using dispersion staining (objective on microscope to determine a materials refractive index) confirmation of refractive index, (extinction angle under polarized light), and birefringence (Polarized Light across or through the material). Materials reported to contain less than 10% may be required to be “Point Counted”, a mathematical method to determine per cent of asbestos fiber in a material. Transmission Electron Microscopy (TEM) is recommended to determine asbestos content in building materials where there are high levels of materials that may block the PLM analyst from seeing the asbestos.
Asbestos in Air
There are two popular methods to determine asbestos content in Air.
The least inexpensive is commonly known as Phase Contrast Microscopy (PCM). The method is titled NIOSH 7400- Asbestos and Other Fibers by PCM. PCM is rather limited and actually can only determine “Fibers in Air”. All fibers longer than 5 microns with a length to width ratio of 3/1 are counted. PCM is comparatively inexpensive and easily accomplished. Sample analysis can run anywhere from $ 7.00 to $ 20.00 dependent upon turn-around time. Analysis by PCM is the only method recognized by OSHA for daily worker Time Weighted Average (TWA) samples.
PCM is also used as the preferred method to determine whether “Release Levels” have been achieved upon completion of a Response Action (Removal, Enclosure, Encapsulation) in a Public or Commercial Building, regardless of how much material has been impacted, or in a School when less than 160 sq. ft. or 260 lin. ft. of asbestos materials has been impacted.
The other analytical method for determining asbestos in air is Transmission Electron Microscopy, (TEM) mentioned earlier. TEM is a definitive method, meaning that the actual asbestos content can be determined. The method can actually differentiate between an asbestos fiber (structure) and other non-asbestos fibers or structures. Where PCM analysis magnifies the material by 400x, TEM magnifies the material by 10,000x. TEM is required as the required method for analysis prior to completion of a Response Action in a Public or Private School when greater than 160 sq. ft. or 260 lin. ft. of material has been impacted. Costs for TEM analysis varies from approximately $ 75.00 to $175.00, dependent upon turn-around time.