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rator; Quantitative fit testing using ambient placed with a high efficiency particulate air
aerosol as the test agent and appropriate in- (HEPA) or P100 series filter supplied by the
strumentation (condensation nuclei counter) to same manufacturer.
quantify the respirator fit; Quantitative fit test-
ing using controlled negative pressure and ap- (4) The sampling instrument shall be selected
propriate instrumentation to measure the so that a computer record or strip chart record
volumetric leak rate of a facepiece to quantify may be made of the test showing the rise and
the respirator fit. fall of the test agent concentration with each
inspiration and expiration at fit factors of at
1. General least 2,000. Integrators or computers that inte-
grate the amount of test agent penetration
(a) The employer shall ensure that persons ad- leakage into the respirator for each exercise
ministering QNFT are able to calibrate equip- may be used provided a record of the read-
ment and perform tests properly, recognize ings is made.
invalid tests, calculate fit factors properly and
ensure that test equipment is in proper work- (5) The combination of substitute air-purifying
ing order. elements, test agent and test agent concentra-
tion shall be such that the test subject is not ex-
(b) The employer shall ensure that QNFT posed in excess of an established exposure
equipment is kept clean, and is maintained limit for the test agent at any time during the
and calibrated according to the manufacturer’s testing process, based upon the length of the
instructions so as to operate at the parameters exposure and the exposure limit duration.
for which it was designed.
(6) The sampling port on the test specimen res-
2. Generated Aerosol Quantitative Fit Testing pirator shall be placed and constructed so that
Protocol no leakage occurs around the port (e.g., where
the respirator is probed), a free air flow is al-
(a) Apparatus. lowed into the sampling line at all times, and
there is no interference with the fit or perfor-
(1) Instrumentation. Aerosol generation, dilu- mance of the respirator. The in-mask sampling
tion, and measurement systems using particu- device (probe) shall be designed and used so
lates (corn oil, polyethylene glycol 400 [PEG that the air sample is drawn from the breath-
400], di-2-ethyl hexyl sebacate [DEHS] or so- ing zone of the test subject, midway between
dium chloride) as test aerosols shall be used the nose and mouth and with the probe ex-
for quantitative fit testing. tending into the facepiece cavity at least 1/4
inch.
(2) Test chamber. The test chamber shall be
large enough to permit all test subjects to per- (7) The test setup shall permit the person ad-
form freely all required exercises without dis- ministering the test to observe the test subject
turbing the test agent concentration or the inside the chamber during the test.
measurement apparatus. The test chamber
shall be equipped and constructed so that the (8) The equipment generating the test atmo-
test agent is effectively isolated from the ambi- sphere shall maintain the concentration of test
ent air, yet uniform in concentration through- agent constant to within a 10 percent variation
out the chamber. for the duration of the test.
(3) When testing air-purifying respirators, the (9) The time lag (interval between an event
normal filter or cartridge element shall be re- and the recording of the event on the strip
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