Environmental sampling data dictionary or schema documentation

NYC 9/11 Public Portal Document

STEL Short term exposure limit. Averaged over 15 minute period or 30 minutes period; STEL is peak exposure. Otherwise, do a duration sampling to get a TWA

TWA; time weighted average

DUST For measure dust by personal air monitoring, use a MEE portable data RAM dust monitor. In our spreadsheet call the Analyte; TOTAL DUST, <10 microns (ConEd data specified that it’s <10 microns)

PCM Phase contrast microscopy. 0.1 fibers per cc by PCM method is the US-OSHA permissible exposure limit for 8 hour time weighted average (TWA). Take a filter, suck in air through it. Counts how many fibers per filter area; can then translate that into a concentration depending on the volume of air that was sucked in. The detection limit can change depending on the volume of air that was sucked in (e.g., lower air volume, lower detection limit). PCM is not able to distinguish btw asbestos, or fiberglass, or other fibers.

TCM Transmission electron microscopy (electron microscope). Characterizes the fibers and specifically identifies asbestos fibers by zapping it with an electron beam; if the fiber melts then it is not asbestos.

Do TEM analysis and compare the S/mm2 per filter paper to the number 70. If at least 1200 liters in a sample, then can compare to clearance level of below 70. (sample is not considered reliable if there are fewer than 500 (?) liters.) Though TEM is most commonly expressed in S/mm2, it can be expressed in fibers per cc b/c know how many cubic cc air went through (pulled in a known volume of air and know the surface area, then know how many fibers per cc were in the sample). 0.01 fee by TEM method is approximately equivalent to indoor clearance level for residences or schools.

PLM Plorized light microscopy. The analysis method for bulk sampling. The percent of asbestos in a sample.

PEL Personal exposure limit - the threshold for occupational exposure like the personal air monitoring

PM2.5 Threshold is 65 ug/m3

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