ASTM D7200-12

Standard Practice for Sampling and Counting Airborne Fibers, Including Asbestos Fibers, in Mines and Quarries, by Phase Contrast Microscopy and Transmission Electron Microscopy (Withdrawn 2021)

SIGNIFICANCE AND USE
5.1 Users of this practice must determine for themselves whether the practices described meet the requirements of local or national authorities regulating asbestos or other fibrous hazards.  
5.2 Variations of this practice have been described by the Asbestos Research Council in Great Britain (8), the Asbestos International Association (AIA) (RTM 1) (9), NIOSH 7400, OSHA (Reference Method ID 160), and ISO 8672. Where the counting rules of these methods differ, this is noted in the text.  
5.3 Advantages  
5.3.1 The technique is specific for fibers. PCM is a fiber counting technique that excludes non-fibrous particles from the analysis.  
5.3.2 The technique is inexpensive, but requires specialized knowledge to carry out the analysis for total fiber counts, at least in so far as the analyst is often required under regulations to have taken a specific training course (for example, NIOSH 582, or equivalent).  
5.3.3 The analysis is quick and can be performed on-site for rapid determination of the concentrations of airborne fibers.  
5.3.4 The procedure provides for a discriminate counting technique that can be used to estimate the percentage of counted fibers that may be asbestos.  
5.4 Limitations  
5.4.1 The main limitation of PCM is that fibers are not identified. All fibers within the specified dimensional range are counted. Differential fiber counting may sometimes be used to discriminate between asbestos fibers and fibers of obviously different morphology, such as cellulose and glass fiber. In most situations, differential fiber counting cannot be used to adequately differentiate asbestos from non-asbestos fibers for purposes of compliance with regulations without additional positive identification. If positive identification of asbestos is required, this must be performed by polarized light or electron microscopy techniques, using a different portion of the filter.  
5.4.2 A further limitation is that the smallest fibers visible by PCM are about 0.2 µ...
SCOPE
1.1 This practice2 describes the determination of the concentration of fibers, expressed as the number of such fibers per millilitre of air, using phase contrast microscopy and optionally transmission electron microscopy to evaluate particulate material collected on a membrane filter in the breathing zone of an individual or by area sampling in a specific location. This practice is based on the core procedures provided in the International Organization for Standardization (ISO) Standard ISO 8672(1)3, the National Institute for Occupational and Health (NIOSH) Manual of Analytical Methods, NIOSH 7400 (2), and the Occupational Safety and Health Administration (OSHA) Method ID 160 (3). This practice indicates the important points where these methods differ, and provides information regarding the differences. However, selecting portions of procedures from different published methods generally requires a user to report that they have used a modification to a method rather than claim they have used the method as written. This practice further gives guidance on how differential counting techniques may be used to indicate where a population of fibers may be asbestos.  
1.2 The practice is used for routine determination of an index of occupational exposure to airborne fibers in mines, quarries, or other locations where ore may be processed or handled. The method gives an index of airborne fiber concentration. The method provides an estimate of the fraction of counted fibers that may be asbestos. This practice should be used in conjunction with electron microscopy (See Appendix X1) for assistance in identification of fibers.  
1.3 This practice specifies the equipment and procedures for sampling the atmosphere in the breathing zone of an individual and for determining the number of fibers accumulated on a filter membrane during the course of an appropriately-selected sampling period. The method may also be used to sample the atmo...

General Information

• Status: Withdrawn
• Publication Date: 14-Oct-2012
• Withdrawal Date: 20-Jan-2021
• ICS: 13.040.30 - Workplace atmospheres
• Technical Committee: D22 - Air Quality
• Drafting Committee: D22.07 - Sampling, Analysis, Management of Asbestos, and Other Microscopic Particles

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D7200 − 12
Standard Practice for
Sampling and Counting Airborne Fibers, Including Asbestos
Fibers, in Mines and Quarries, by Phase Contrast
1
Microscopy and Transmission Electron Microscopy
This standard is issued under the fixed designation D7200; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.3 Thispracticespecifiestheequipmentandproceduresfor
2 samplingtheatmosphereinthebreathingzoneofanindividual
1.1 This practice describes the determination of the con-
and for determining the number of fibers accumulated on a
centration of fibers, expressed as the number of such fibers per
filter membrane during the course of an appropriately-selected
millilitreofair,usingphasecontrastmicroscopyandoptionally
sampling period. The method may also be used to sample the
transmission electron microscopy to evaluate particulate mate-
atmosphere in a specific location in a mine or in a room of a
rial collected on a membrane filter in the breathing zone of an
building (area sampling).
individual or by area sampling in a specific location. This
practice is based on the core procedures provided in the
1.4 The ideal working range of this practice extends from
2 2
International Organization for Standardization (ISO) Standard 100 fibers/mm to 1300 fibers/mm of filter area. For a 1000-L
3
ISO8672(1) , the National Institute for Occupational and
air sample, this corresponds to a concentration range from
3
Health (NIOSH) Manual of Analytical Methods, NIOSH approximately 0.04 to 0.5 fiber/mL (or fiber/cm ). Lower and
7400(2), and the Occupational Safety and Health Administra-
higher ranges of fiber concentration can be measured by
tion (OSHA) Method ID160 (3). This practice indicates the reducing or increasing the volume of air collected. However,
important points where these methods differ, and provides
whenthispracticeisappliedtopersonalsamplinginminesand
information regarding the differences. However, selecting por- quarries,theleveloftotalsuspendedparticulatemayimposean
tionsofproceduresfromdifferentpublishedmethodsgenerally upperlimittothevolumeofairthatcanbesampledifthefilters
requires a user to report that they have used a modification to produced are to be of appropriate particulate loading for fiber
a method rather than claim they have used the method as counting.
written. This practice further gives guidance on how differen-
1.5 Users should determine their own limit of detection
tial counting techniques may be used to indicate where a
using the procedure in Practice D6620. For reference, the
population of fibers may be asbestos.
NIOSH 7400 method gives the limit of detection as 7 fibers/
2
1.2 The practice is used for routine determination of an
mm offilterarea.Fora1000-Lairsample,thiscorrespondsto
3
index of occupational exposure to airborne fibers in mines,
a limit of detection of 0.0027 fiber/mL (or fiber/cm ). For
2
quarries, or other locations where ore may be processed or
OSHAID160 the limit of detection is given as 5.5 fibers/mm
handled. The method gives an index of airborne fiber concen-
of filter area. For a 1000-L air sample, this corresponds to a
3
tration. The method provides an estimate of the fraction of
limit of detection of 0.0022 fiber/mL (or fiber/cm ).
counted fibers that may be asbestos. This practice should be
1.6 If this practice yields a fiber concentration that does not
used in conjunction with electron microscopy (see Appendix
exceed one-half the permissible exposure limit or threshold
X1) for assistance in identification of fibers.
limit value for the particular regulated fiber variety, no further
action may be necessary. If the fiber concentration exceeds
one-half of the regulated permissible exposure limit or thresh-
1
ThispracticeisunderthejurisdictionofASTMCommitteeD22onAirQuality
old limit value for the particular regulated fiber variety, it is
and is the direct responsibility of Subcommittee D22.07 on Sampling andAnalysis
necessary to examine the data to determine if more than 50 %
of Asbestos.
of the counted fibers are thinner than 1.0 µm, or thicker but
Current edition approved Oct. 15, 2012. Published November 2012. Originally
approved in 2006. Last previous edition approved in 2006 as D7200 – 06.
withanappearanceofasbestos(curvature,splayedends,orthe
DOI:10.1520/D7200-12.
appearance of a bundle).
2
This test method is based on NIOSH 7400, OSHA Method ID60, and
ISO8672. Users of this ASTM standard are cautioned that if they wish to comply
1.7 The mounting medium used in this practice has a
with one of these specific procedures exactly they should follow that procedure,
refractive index of approxi
...