NYC 9/11 Public Portal Document
ASBESTOS and OTHER FIBERS by PCM: METHOD 7400, Issue 2, dated 15 August 1994 - Page 2 of 15
REAGENTS: EQUIPMENT:
1. Acetone,* reagent grade. 1. Sampler: field monitor, 25-mm, three-piece
2. Triacetin (glycerol triacetate), reagent grade. cassette with ca. 50-mm electrically
conductive extension cowl and cellulose ester
filter, 0.45- to 1.2-pm pore size, and backup
pad.
NOTE 1: Analyze representative filters for
* See SPECIAL PRECAUTIONS. fiber background before use to
check for clarity and background.
Discard the filter lot if mean is >5
fibers per 100 graticule fields.
These are defined as laboratory
blanks. Manufacturer-provided
quality assurance checks on filter
blanks are normally adequate as
long as field blanks are analyzed
as described below.
NOTE 2: The electrically conductive
extension cowl reduces
electrostatic effects. Ground the
cowl when possible during
sampling.
NOTE 3: Use 0.8-pm pore size filters for
personal sampling. The 0.45-pm
filters are recommended for
sampling when performing TEM
analysis on the same samples.
However, their higher pressure
drop precludes their use with
personal sampling pumps.
NOTE 4: Other cassettes have been
proposed that exhibit improved
uniformity of fiber deposit on the
filter surface, e.g., bellmouthed
sampler (Envirometrics,
Charleston, SC). These may be
used if shown to give measured
concentrations equivalent to
sampler indicated above for the
application.
2. Personal sampling pump, battery or line-
powered vacuum, of sufficient capacity to
meet flow-rate requirements (see step 4 for
flow rate), with flexible connecting tubing.
3. Wire, multi-stranded, 22-gauge; 1", hose
clamp to attach wire to cassette.
4. Tape, shrink- or adhesive-.
5. Slides, glass, frosted-end, pre-cleaned, 25 x
75-mm.
6. Cover slips, 22- x 22-mm, No. 1-1/2, unless
otherwise specified by microscope
manufacturer.
7. Lacquer or nail polish.
8. Knife, #10 surgical steel, curved blade.
9. Tweezers.
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94
NYC-WTC_000149406
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