NYC-WTC_000209427

NYC 9/11 Public Portal Document

Even if the air v as tested using large volumes of air in order to increase the sensitivity, compared to the AHERA TEM clearance test, it may not be practical. This is because of the long time required (8 hours for a 4800 liter sample) houis, and the expense (around $400 for the lab fee if 32 “grids” of the; filter are read by the analyst). There would need to be people present dining the 8 hours not only to insure that no one sabotaged the test by cutting the pump off or spread asbestos during pumping, but also because the test would need to represent air conditions during normal human activities. If the air was tested with no people present, the results would be umealistically low, since normal human activities stir up asbestos and cause it to become airborne.

The ultrasonicati on method is not likely to result in an over-count of asbestos fibers due to the separation of bundles of fibers during the sonication procedure. This is particularly true for WTC fallout, which is already finely divided.® High impacts, such as foot traffic or children playing with toys on carpets, would certainly result in the breakdown of asbestos fibers that are bundled together into individual asbestos, resulting in an increase in the number of fibers, and also an increase in the hazard.

Finding a iab and submitting samples

First, locate a laboratory who will perform ultrasonication tests of carpet, upholstery, and draperies. There is a list of accredited asbestos laboratories maintained by the National Institute for Standards and Technology (NIST) on the internet, or call the NIST at the number in the reference section..’'

Then call the lab and ask if they can perform “EPA’s ultrasonication extraction asbestos method for carpet, the Millette method.”® Use this phi'ase to describe the test when talking to the lab. The EPA method number is EPA-600/J-93/167, but most lab receptionists will not recognize the method by just this number. Because this is a less common method, you may need to speak to the lab director.

Ask which partic;ular one of their labs does this test, and where to send the sample. This test is usually done at only one of their lab locations. Ask the lab for instructions for sending the sample. Labs will refuse your samples if you do not follow their instructions exactly. Carpet and fabric samples should be enclosed in double Ziplock® sealed baggies.

Laboratories will require that you fill out their Chain of Custody form. Often you can download the chain of custody form from their web site, or they will fax it to you. You must indicate on

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