Document 9nyVQ1DMZROrk64y7N1zd7mq
22740:
Kederak Register / Vol. 5t, No. i!9 / Friday. June 20,. 1986 / Rules and; Regulations
2. Interiaboratory.progrant Each laboratory analyzing asbestos, tremolite, anthophyllite, andactino)ite;sajnple8.for.compliance. determinatlonshall implemenlan interlaboratory quality assurance program-
that as a minimum includesiparticipationof. at least twotother independent laboratories. Each laboratory shall.participate imround. robin tesUng;eUea8t once.every, e.months,
withiat,least aU.the other.laboratories in its . interlaboratory/quafity assurance group. Each':
laboratory. sKallisubmit slides. typical of its own work load for use instKls program. THe
round robin.sHair.be designed and results analyzed'using appropriate statistical
methodology.. 3. AH! individuals performingasbegtos.
tremolite, anthophyllite, arid'actinolite analysis must'have taken the NIOSH course for sampling and evaluating.airborne asbestos; tremolite, anthophyllite;.and. actinolite dust or an equallvalent course.
4. When the use of different microscopes
contributes.to differences between counters and laboratories, the effect of the different microscope shall be evaluated and the microscope shall be replaced; as necessary:
5. Current results of these-quality assurance programs shalVba poatedln each
laboratory to keep the-mlcroscopists informed.
Appendlx. B to ;1910.1001--Detailed' Procedure for.Asbostos-Tremolite,. Anthophyllite, and Actinolite Sampling and ' Analysis---Noo-Mandatory;-
This-appendlx<.cantains.a.detailed ' procedure- forsampling and analysisandr includes those critical elements-specified-inAppendix A..Bmployers are-notrequired.lo use thfsprocedure, buttheyare.requiredto use Appendix'A..The purposeof Appendix B is to provide a detailed step-by-step sampling, and analysisiprocedure that conforms to the elements specified in Appendix.A..Since.this, procedure may.also-standardize the analysis and reduce-variability, OSHA encourages employers to use this appendix.
Asbestos, Tremolite,AntHppfiyllite, and Actinolite Sampling and'Ahalysis Method-
Technique:.Microscopy, Phase Contrast
Analyte: Fibers (manual count)-
Sample-Preparation:.Acetone/triacetin.
method Calibration:. Phase-shift detection limit,
about 3-degreesRange:-i00 toil300fibers/mm,2 filter,
areaEstimated limit of detection: 7 fibers/
mm.2 filter. area ' Sampler Filter (0.8-1.2 um.mixed;
cellulose ester membrane, 25-mm
diameter)
. Flow rate:.0:5 l/min to 2.5 l/min:(25-mm cassette} 1.0 l/min to 2.5'l/min (37-
mm cassette)'
Sample volume:-Adjust to obtain 100 to. 1300 fibers/mm 2
Shipmenb.Roiitine-
.
Sample stability: Indefinite
Blanks: 10% of samples (imninuim.2)
Standard-analytical,error 0.25..
Applicability: The working range is-0:02 f/ cc (1920-L air sample) to:1.25 f/cc (40fr-L air
sample). The method gives an< index of airborne asbeBtoB: tremolHe.amhophyHite. endactinolitefibere but.may be used for othermaterialbisuch-as fibrous glass.by Inserting suitable parameters into the countingttules. The method-does not. differenUate-between asbestos,tremolite,. anthophy)lite,-.and*acUnolite'and other-fibers.. Asbestos..tremolite. anthophyllite,,and actinolite.fibereless than oa..O;25umdiameter wlh not^be.detected.by this.method..
Interferences:-Any other airborne fiber may. interfere sinceall particles.meeting.the
counting criteria are counted. Chainlike. particles may appear fibrous. High levels of nonfibrous dust particles may. obscure fibers in the field of view and raise the detection limit.
Reagents:.]:.Acetone: 2-Triacetin.{glycerol triacetate), reagentgrade
Special precautions:.Acetone is an extremely flammable liquld and precautions
must be taken not to ignite It;.Heating.of acetone roust.be;done ina ventilated laboratory fumethood using a.flameless;. epark-freeheat source
Equipment: l. CoI!ection device: 254mm
cassette with 50-mm extension-cowhwith; ceUulbse;ester.fiIter,.0J:tD.1.2:mm pore sizeend backup pad.
Note: Analyze representative filters-for fiber background before use and discard.the filter lot if morethan 5 fibers/lOO fields are) found.
2. Personal samplingipumpt.greater than or. equal to 0.5L/min. with flexible connecting tubing.
3.. Microscope*,phase contrast, with greenor blue filter, Bto 10X eyepiece,. and 40;to 45X phase ob(ective (total magnificatiorvcav400X;. numerical.aperture 0.65.to 0.75.
4; Slides. glass, single-fro9ted,.pre?cleaned,25 x 75 mm.
5. Cover slips, 25 x 25 mm, no. unless otherwise specified by microscope, manufacturer.. . .
6. Knife, No:.1 surgical steel, curved blade; 7.Tweezer8. 6;.Flask,.Guth-type, insulated-neck,.250. to 500 mL.fwith single-holed rubber stopper, and elbow-jointed glas9.tubing.16 to. 22 cm long).. 0. Hotplate, spark-free, stirring type:, heating mantle:.or infrared lamp and magnetic stirrer.: 10..5yringe, hypodermic, with 22rgauge needle. 11.-Graticule. Walton-Beckett type with 100 umi diameler.circular. field at the specimen plane(area = 0.Q07B5.mm 8). (Type G-22).
Note.--the graticule is custom?made for each, microscope..
12. HSE/NPL.phase contrast test slide,. M'arklL - 13. Telescope, ocular phase-ring centering.
14. Stage micrometer (0.01 mm divisions).
Sampling.
-1. Calibrate each personahsamp.ltrig pump with a representative sampler in line.
2; Fasten the-sampler to-the worker's lapel as.close as possible to the worker's mouth. Remove the lop cover from Oie-end of the cowl extension (open face)'andorient face down. Wrap the-joint betweenthe extender and the monitor's body with shrink tape to
prevent air leaks. 3. Submit at leost^two blanks (or l0% ofthe
total samples, whichever is greater) for each
set of samples..Remove the.caps from the
field btank;cas9eUes and! store the caps.and cassettes.in a clean area (bag or box) during the sampling period: Replace the capslrathe cassettes when sampling-is completed. -
4. Sample at 0.5 L/min or greater. Do notexceed 1-rog-total dust loading on-the filter;. . Adjust sampling flow rat'e,.Q,(L/min); and. limettbiprodiica a. fiberdensity..E (fibers/' mma),,of l00 to l300 flbers/.tn* |3;85xl04 to 5x10? fibere per 25-mm filter with effective^ collection area (A=385 mma)) for.optimum counting precision!(seestep.21.below).
Calculate, the. minimum sampling time, tminimum.(min)a( the action level (one-half of the current standard), L (f/cc) of the fibrous aerosol being sampled:
(Ac)(E)
tnlo ='
(Q)(L)10ai
5. Remove-the field monitor at the end of sampling*, replace the plasticdop cover and smalhend caps;.and store.the.monitor..
6; Ship the9amples in.a.rigidtcontainer
with sufficient'packing material to-prevent fosllingior damage.
Note.--Do not use polystyrene, foam In the shipping container because of electrostatic, forces which may cause fiber loss from the sampler, filter.
Sample.Preparation
Note^-The object is to produce samples,
with a smooth (non-grainy) background in.a
medium with-a refractiveindex.equal to or-
less than 1.4B. The.method below collapses
the filter, for, easier focusing.and produces .
permanent mounts which are.useful for
quality control'and interlaboratory
comparison. Other mounting techniques
meeting the above criteria may also-be-used,
e g., the nonpermanent field mounting
technique used in P & CAM 239.
7. Ensure that the glass slides and cover
slips are free of dust.and'-fibers.
8: Place 40;to 60 ml.of aceloneintoa-Gufh-
type flask. Stopper the flask with a single-
hole rubber stopper, through which a glass
tube extends 5 to 8 cm into the flask..The
portion.oLtheglass tube that exits the top.of
the stopper (8*to 10 cm):is bent downward in.
an elbow that makes an angje of 20`to 30'
degrees with.the horizontal:
9: Place the flask.in a stimng:hbtplatedr.
wrap ln:a-heating mantle: Heat theocetone
gradually to its boiling temperature-.(ca: 58
`C).
Caution.---1The acetone vapor must be
generated in a.ventilated fume hood.away.
from all open flames and spark sources.
Alternate heating methods can be used,
providing no open flame or sparks are
present.
.
10: Mount either tKe.-whole'Sampfe filter or
a wedge cut from the sample filter on a clean
glass-slide.
a. Cut wedges of ca. 25 percent of. the filter
area with-a curved-blade steel surgical knife
using a.rocking motion.to prevent tearing..
GLEASON-000988