ASTM D4532-22

Standard Test Method for Respirable Dust in Workplace Atmospheres Using Cyclone Samplers

SIGNIFICANCE AND USE
5.1 This test method covers the determination of respirable dust concentration in workplace atmospheres.  
5.2 Variations of the test method are in world-wide use for determining compliance relative to occupational exposure levels.  
5.3 The test method may be used to verify dust control measures.  
5.4 The test method may also be applied in research into health effects of dust in an occupational setting.
SCOPE
1.1 This test method provides details for the determination of respirable dust concentration defined in terms of international convention in a range from 0.5 mg/m3 to 10 mg/m3 in workplace atmospheres, depending on sampling time. Specifics are given for sampling and analysis using any one of a number of commercially available cyclone samplers.  
1.2 The limitations on the test method are a minimum weight of 0.1 mg of dust on the filter, and a maximum loading dependent on sampler type and time of sampling. The test method may be used at higher loadings if the flow rate can be maintained constant.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 This test method contains notes that are explanatory and are not part of the mandatory requirements of the method.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 14-Nov-2022
• ICS: 13.040.99 - Other standards related to air quality
• Technical Committee: D22 - Air Quality
• Drafting Committee: D22.04 - Workplace Air Quality

Relations

• Refers: ASTM D7440-23 - Standard Practice for Characterizing Uncertainty in Air Quality Measurements
• Effective Date: 01-Sep-2023
• Refers: ASTM D1356-20a - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 01-Sep-2020
• Refers: ASTM D1356-20 - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 15-Mar-2020
• Refers: ASTM D6062-19 - Standard Guide for Personal Samplers of Health-Related Aerosol Fractions
• Effective Date: 01-Apr-2019
• Refers: ASTM D1356-15a - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 15-Oct-2015
• Refers: ASTM D1356-15 - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 01-Jul-2015
• Refers: ASTM D7440-08(2015)e1 - Standard Practice for Characterizing Uncertainty in Air Quality Measurements
• Effective Date: 01-Jul-2015
• Refers: ASTM D1356-14b - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 01-Dec-2014
• Refers: ASTM D1356-14a - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 01-May-2014
• Refers: ASTM D1356-14 - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 15-Jan-2014
• Refers: ASTM E1-13 - Standard Specification for ASTM Liquid-in-Glass Thermometers
• Effective Date: 01-May-2013
• Refers: ASTM D6062-07(2012) - Standard Guide for Personal Samplers of Health-Related Aerosol Fractions
• Effective Date: 01-Apr-2012
• Refers: ASTM D5337-11 - Standard Practice for Flow Rate for Calibration of Personal Sampling Pumps
• Effective Date: 15-Nov-2011
• Refers: ASTM D6552-06(2011) - Standard Practice for Controlling and Characterizing Errors in Weighing Collected Aerosols
• Effective Date: 01-Oct-2011
• Refers: ASTM E2251-11 - Standard Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision Liquids
• Effective Date: 01-May-2011

Overview

ASTM D4532-22 is the internationally recognized standard test method for determining respirable dust concentrations in workplace atmospheres using cyclone samplers. Developed by ASTM International, this test method provides procedures for sampling and analysis of airborne respirable dust to ensure occupational health and safety. It addresses global demands for accurate workplace air quality monitoring, helping organizations assess compliance with occupational exposure limits and verify dust control effectiveness.

The standard covers use of a variety of commercially available cyclone samplers and defines the respirable dust fraction according to international conventions. It supports exposure assessment, regulatory compliance, and industrial hygiene practices across multiple industries concerned with respirable dust hazards.

Key Topics

• Scope and Application: Covers measurement of respirable dust within the range of 0.5 mg/m³ to 10 mg/m³, depending on sampling time. Applicable to a wide array of workplace environments.
• Cyclone Samplers: Details the requirements for high and medium flow rate cyclone sampling devices, emphasizing their role in separating the respirable fraction of airborne particles for analysis.
• Sampling Methodology: Describes the use of personal sampling pumps, filter cassettes, and the proper placement of devices in the worker’s breathing zone for valid data collection.
• Analytical Procedures: Specifies procedures for filter weighing, controlling sample contamination, and ensuring sample integrity during transport and handling.
• Quality Assurance and Uncertainty: Sets expectations for calibration, environmental controls, and calculation of uncertainty in measurement results, promoting traceability and reliable data for occupational exposure assessments.
• Data Reporting: Outlines requirements for comprehensive reporting, including sampling conditions, measured concentrations, uncertainty assessments, and procedural notes.

Applications

ASTM D4532-22 delivers practical value in several key areas:

• Occupational Health and Safety: Enables industrial hygienists and safety professionals to monitor airborne respirable dust and verify compliance with regulatory exposure limits.
• Dust Control Verification: Assists in the evaluation and validation of workplace dust reduction or mitigation strategies, contributing to improved worker protection.
• Exposure Assessment: Provides a standardized approach for exposure assessment in industries such as mining, construction, manufacturing, and other sectors where airborne particulate matter is a concern.
• Research and Epidemiology: Supports scientific investigations into the health effects of respirable dust exposure in occupational settings, facilitating robust and repeatable data collection.

By adhering to this standard, organizations can ensure the collection of reliable data for informed decision-making and compliance with international best practices.

Related Standards

The following standards complement or are referenced by ASTM D4532-22:

• ASTM D1356: Terminology relating to sampling and analysis of atmospheres.
• ASTM D3195: Practice for rotameter calibration.
• ASTM D5337: Practice for flow rate adjustment of personal sampling pumps.
• ASTM D6062: Guide for personal samplers of health-related aerosol fractions.
• ASTM D6552: Practice for controlling and characterizing errors in weighing collected aerosols.
• ASTM D7440: Practice for characterizing uncertainty in air quality measurements.
• ISO 7708 / EN 481: International standards defining particle size fractions for health-related workplace sampling.
• ISO 13137, ISO 15767, ISO 18158: Standards related to personal sampling pump requirements and aerosol measurement terminology.

Keywords: respirable dust, cyclone sampler, workplace atmospheres, occupational exposure, air monitoring, dust control, industrial hygiene, ASTM D4532-22.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D4532 − 22
Standard Test Method for
Respirable Dust in Workplace Atmospheres Using Cyclone
Samplers
This standard is issued under the fixed designation D4532; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope D1356 Terminology Relating to Sampling and Analysis of
Atmospheres
1.1 This test method provides details for the determination
D3195 Practice for Rotameter Calibration
of respirable dust concentration defined in terms of interna-
3 3 D5337 Practice for Flow RateAdjustment of Personal Sam-
tional convention in a range from 0.5 mg⁄m to 10 mg⁄m in
pling Pumps
workplaceatmospheres,dependingonsamplingtime.Specifics
D6062 GuideforPersonalSamplersofHealth-RelatedAero-
are given for sampling and analysis using any one of a number
sol Fractions
of commercially available cyclone samplers.
D6552 Practice for Controlling and Characterizing Errors in
1.2 The limitations on the test method are a minimum
Weighing Collected Aerosols
weight of 0.1 mg of dust on the filter, and a maximum loading
D7440 Practice for Characterizing Uncertainty in Air Qual-
dependent on sampler type and time of sampling. The test
ity Measurements
method may be used at higher loadings if the flow rate can be
E1 Specification for ASTM Liquid-in-Glass Thermometers
maintained constant.
E2251 Specification for Liquid-in-Glass ASTM Thermom-
eters with Low-Hazard Precision Liquids
1.3 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
2.2 Other International Standards:
standard. ISO GUM Guide to the Expression of Uncertainty in
Measurement, ISO Guide 98
1.4 This test method contains notes that are explanatory and
ISO 7708 Air Quality—Particle Size Fraction Definitions
are not part of the mandatory requirements of the method.
for Health-Related Sampling
1.5 This standard does not purport to address all of the
ISO 13137 Workplace Atmospheres – Pumps for Personal
safety concerns, if any, associated with its use. It is the
Sampling of Chemical and Biological Agents – Require-
responsibility of the user of this standard to establish appro-
ments and Test Methods
priate safety, health, and environmental practices and deter-
ISO 15767 WorkplaceAtmospheres—Controlling and Char-
mine the applicability of regulatory limitations prior to use.
acterizing Errors in Weighing Collected Aerosol
1.6 This international standard was developed in accor-
ISO 18158 Workplace Atmospheres - Terminology
dance with internationally recognized principles on standard-
EN 481 Workplace Atmospheres—Size Fraction Definitions
ization established in the Decision on Principles for the
for the Measurement of Airborne Particles in the Work-
Development of International Standards, Guides and Recom-
place
mendations issued by the World Trade Organization Technical
EN 13205 Workplace Atmospheres—Assessment of Perfor-
Barriers to Trade (TBT) Committee.
mance of Instruments for Measurement of Airborne Par-
ticle Concentrations
2. Referenced Documents
3. Terminology
2.1 ASTM Standards:
3.1 For definitions of terms used in this test method, refer to
Terminology D1356.
This test method is under the jurisdiction of ASTM Committee D22 on Air
3.2 Definitions of Terms Specific to This Standard:
Quality and is the direct responsibility of Subcommittee D22.04 on Workplace Air
Quality.
3.2.1 respirable fraction—mass fraction of total airborne
Current edition approved Nov. 15, 2022. Published January 2023. Originally
particles which penetrate to the unciliated airways. (ISO
approved in 1985. Last previous edition approved in 2015 as D4532 – 15. DOI:
18158)
10.1520/D4532-22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4532 − 22
3.2.2 respirable sampler—aerosol sampler that is used to 5.4 The test method may also be applied in research into
collect the fraction of airborne particles according to the health effects of dust in an occupational setting.
respirable convention (see Terminology D1356) from the
6. Apparatus
surrounding air. (modified from ISO 18158)
6.1 Sampling Unit—The sampling unit consists of a pump,
3.2.2.1 Discussion—Fig. 1 shows the collection efficiency
a sampling head, and tubing connecting the pump and outlet of
of an idealized sampler following the internationally-
the sampling head. The sampling head consists of a cyclone
harmonized sampling conventions of ISO 7708, EN 481,
4 and a filter assembly.
Guide D6062, and Ref. (1).
6.1.1 Respirable Dust Cyclone—Various types of respirable
NOTE 1—The definition of the respirable convention is a compromise
dust cyclones are commercially available. In general, these
between previous definitions, available samplers, and the fraction of dust
samplers can be categorized into two groups, high flow rate
that penetrates to (rather than deposits in) the alveolar region of the lung.
cyclone samplers (flow rate range 4.2 L⁄min – 10 L⁄min) and
Local legal definitions may differ from the definition adopted in this test
medium flow rate cyclone samplers (flow rate range 1.7 L⁄min
method.
– 2.75 L⁄min). High flow rate samplers should be considered
3.3 For terms and definitions related to characterizing
for workplaces where airborne particle concentrations are low
uncertainty, see ISO GUM (ISO Guide 98) and Practice
(for example, <0.05 mg/m ) or where it is desirable to take
D7440.
short-term exposure measurements (for example, <4 h) (2-4).
6.1.1.1 Bias relative to the international respirable dust
4. Summary of Test Method
criterion and the dust size distribution being sampled (2-13)
4.1 Air is drawn through a cyclone or equivalent sampler
must be controlled sufficiently (see 13.2.4) for the application
followed by a tared filter, which is then re-weighed to deter-
of intended use.
mine the mass of respirable dust. The air flow rate and time of
6.1.2 Filter Cassette Assembly—Filter, filter-support pad,
sampling provide the volume from which the dust mass was
and filter cassette holder with suitable caps. The filter shall be
sampled. A time-weighted average respirable dust concentra-
non-hygroscopic and provide a collection efficiency greater
tion is calculated by dividing the mass by the total air volume.
than 95 % for the dust of interest.
NOTE2—Samplersalternativetoacyclone(forexample,foam-basedor
6.1.2.1 As an example, most glass fiber and membrane
personal cascade impactors) are commercially available. Nevertheless,
filters with nominal pore size of 5 µm will fulfill this require-
this test method is limited to cyclone samplers.
ment (14). PVC filters are recommended for gravimetric
analysis. The equilibrated filter is preweighed by the user.
5. Significance and Use
6.1.2.2 It is preferable to use a conductive cassette because
5.1 This test method covers the determination of respirable
electrostatic charge on the dust and a non-conductive cassette
dust concentration in workplace atmospheres.
can result in a significant bias (15-20). For controlling dust
5.2 Variations of the test method are in world-wide use for
which may become attracted to the interior cassette walls,
determining compliance relative to occupational exposure
several filter holders equipped with a shielded respirable dust
levels.
filter and cassette are commercially available, which may be
weighed together with the filter.
5.3 The test method may be used to verify dust control
6.1.3 Personal Sampling Pump—With a flow rate uncer-
measures.
tainty (see 13.2.1) less than 5 %. The pump pulsation ampli-
tudemaynotexceed 610 %ofthemeanflowaccordingtoISO
The boldface numbers in parentheses refer to a list of references at the end of 13137 method (21) or 625 % of the mean flow if pump
this standard.
pulsation is measured at the inlet of the cyclones (22). The
nominal sampling flow rate for each cyclone type is adjusted
using Practice D5337.
NOTE 3—Cyclone samples collected with pulsating flow have been
shown to yield a negative bias as large as 70 % compared to samples
collected under steady flow (22).
6.2 Charger—Pumps shall be completely charged with an
appropriate charger or with replacement disposable batteries,
following manufacturer’s instructions.
6.3 Weighing Room—With temperature (20 °C 6 2 °C) and
humidity (50 % Relative Humidity (RH) 6 5 % (RH)) control
to allow weighing with an analytical balance to accuracy
required. See ISO 15767 and Practice D6552 for controlling
and characterizing errors in weighing collected aerosols.
6.3.1 If a weighing room is not available, a filter equilibra-
tion chamber can be used to equilibrate the filters in a
temperature (20 °C 6 2 °C) and humidity (50 % RH 6 5%
FIG. 1 Collection Efficiency of an Ideal Sampler Following the
International Sampling Conventions RH) controlled chamber.
D4532 − 22
6.4 Analytical Balance—Capable of weighing to 0.01 mg or 8. Sampling
better, depending on application. Particular care must be given
8.1 Remove the filter holder caps and connect the filter
to the proper zeroing of the balance.
holder to the cyclone as required by the manufacturer. Connect
6.5 Charge Neutralizer—To eliminate static charge in the
the outlet of the sampling head to the calibrated pump’s inlet
balance case and on the filters during weighing. Po-210
with a piece of flexible tubing. Make sure all connections are
neutralizers if used must be replaced within nine months of
free of leaks by closing off the filter inlet.
their production date.
8.2 Attach the sampling head to the worker so that it is
6.6 Plane-Parallel Press—Capable of giving a force of at
located in the breathing zone. The sampling head shall be
least 1000 N (may be required if plastic filter holders are used
placed in such a manner to prevent dust from falling into it and
that must be pressed together after insertion of the filter).
to avoid restricting the inlet. The pump can be attached to the
worker’s belt.
6.7 Flow Meter—Measuring volumetric flow with precision
equal to 2 % or better within the range of the flow rate used.
8.3 Initiate sampling by turning the pump on and record the
Various flow meters are introduced in Practice D5337. Flow
flow rate and the time. For long-term sampling, periodically
verification of rotameters can be performed using Practice
check the pump to determine whether the pump functions
D3195.
properly. If a noticeable change of the flow rate is visually
observed due to bending or blockage of tubing, turn off the
6.8 Thermometer—Capable of covering the temperature
pump and reset the flow rate. If unable to reset the flow rate to
rangeofinterestwithdivisionsevery0.1 °C(seeSpecifications
the original setting, terminate sampling and note the reason for
E1 and E2251).
termination.
6.9 Flexible Tube with Two Clips—One near the sampling
8.3.1 Depending on sample load, consecutive samples over
head, if the sampling head does not have a clip, and the other
the shift may be required. However, the sampling time should
midway between the sampling head and the pump. The length
not exceed the operating life of the batteries or the prevailing
of the tube is dependent on how the sampling unit is worn. A
“full shift.” The nominal sampling period is eight hours.
length of 0.7 m to 0.9 m is suitable if the pump is attached to
Sampling times shorter than a full shift are permitted if the
the worker’s belt.
following occurs:
6.10 Forceps—Preferably nylon.
The pressure drop across the filter exceeds the pump’s
capabilities; that is, the filter becomes clogged.
6.11 Rod or filter lifter.
Specific working operations of shorter duration (for
6.12 Petri Dishes or Filter Keepers—With diameter slightly
example, task-based exposures) are to be investigated.
greater than the filter.
Determinations of variations of the exposure during a shift
6.13 Tape—Adhesive (for example, plastic electrical), for
are made.
sealing samplers.
8.3.2 The sampler must be observed during sampling to the
extent possible in order to ensure that it is not inverted at any
7. Preparation of Samplers Prior to Sampling
time, otherwise re-deposition of particles from the cyclone
7.1 Inspect the interior of the cyclone and clean it to ensure body onto the filter may occur. Instances of inversion, whether
no re-entrainment of large particles. If the inside surfaces are observed directly or reported by the person being sampled
visibly scored, replace the cyclone since the dust separation should be included in the report.
characteristics of the sampler might be altered.
8.4 Attheendofthesamplingperiod,turnthepumpoffand
7.2 Equilibrate all the filters in an environmentally con-
record the final flow rate and time.
trolled weighing room or equilibration chamber for at least
8.5 Remove the sampling unit from the worker and care-
24 h.
fully take the sampling equipment to a clean, dust-free area.
7.3 Weigh the filters in the weighing room.
8.6 Measure the pump flow rate using the calibrated flow
7.3.1 Internally calibrate the balance (zero balance) before
meter(seePracticeD5337forthemeasurementandadjustment
use.
of flow rate). If the flow rates before and after sampling differ
7.3.2 Grasp the filter with forceps and pass the filter several
by more than 5 %, consider the sample to be invalid.
times through a charge neutralizer to eliminate static charge, if
8.7 Remove the filter holder from the sampling head and
necessary.
replace the filter holder caps.
7.3.3 Record the weight of filters.
8.8 For each set of ten or fewer samples, submit a field
7.4 Place the tared filter and filter support in the filter
blank sample.The filters and filter holders to be used as blanks
cassette holder, close firmly, and tape the circumference of the
arepreparedandtransportedinthesamemannerasthesamples
filter holder with adhesive tape. If necessary, use the press
exceptthatnoairisdrawnthroughthem.Labeltheseasblanks.
described in 6.6.
7.5 Place caps on the filter holder and suitably cover the 8.9 The filter assembly should be returned to the laboratory
assembly to avoid contamination if it is held for any time prior in a suitable container designed to prevent sample damage in
to use. transit.
D4532 − 22
8.9.1 The preferred procedure is to personally transport M 5 m 2 m 2 δm (1)
~ !
s 2 1 b
samples back to the laboratory such as by car or carry-on
where:
aircraft baggage. If collected samples need to be shipped by a
m = tare weight (mg) of the filter before sampling,
shipping service, place sample packages inside larger boxes
m = mass (mg) of the filter plus aerosol sample, and
and cushion with packing materials.
δm = average mass increase or decrease (mg) of the blank
b
filter.
9. Flow Rate Adjustment and Standardization
9.1 Air flow rate adjustment of the sampling unit should be 11.2 The sampled volume V (m ) is:
s
completed before each sampling session. Maintenance and
V 5 Qt / 1000 L/m (2)
~ ! ~ !
s
repairs, according to the manufacturer’s instructions, should be
where:
performed on a regular schedule and records kept for docu-
mentation. See Practice D5337 for guidance on flow rate Q = mean flow rate (L/min) of air sampled, and
adjustment. t = sampling time (min).
9.1.1 Make sure that the pump is connected to an appropri-
11.3 The concentration C (mg/m ) of the respirable dust in
atesamplingtrain,intheorderofpump,tubing,inletofsample
the sampled air is:
media holder, and the cyclone connected to the sample media
C 5 M /V (3)
s s
holder.
9.1.2
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D4532 − 15 D4532 − 22
Standard Test Method for
Respirable Dust in Workplace Atmospheres Using Cyclone
Samplers
This standard is issued under the fixed designation D4532; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method provides details for the determination of respirable dust concentration defined in terms of international
3 3
convention in a range from 0.50.5 mg ⁄m to 10 10 mg mg/m⁄m in workplace atmospheres. atmospheres, depending on sampling
time. Specifics are given for sampling and analysis using any one of a number of commercially available cyclone samplers.
1.2 The limitations on the test method are a minimum weight of 0.1 mg of dust on the filter, and a maximum loading of 0.3
mg/mdependent on the filter. sampler type and time of sampling. The test method may be used at higher loadings if the flow rate
can be maintained constant.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 This test method contains notes that are explanatory and are not part of the mandatory requirements of the method.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to consult and establish appropriate safety safety, health, and healthenvironmental practices and
determine the applicability of regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D1356 Terminology Relating to Sampling and Analysis of Atmospheres
D3195 Practice for Rotameter Calibration
D5337 Practice for Flow Rate Adjustment of Personal Sampling Pumps
D6062 Guide for Personal Samplers of Health-Related Aerosol Fractions
D6552 Practice for Controlling and Characterizing Errors in Weighing Collected Aerosols
D7440 Practice for Characterizing Uncertainty in Air Quality Measurements
E1 Specification for ASTM Liquid-in-Glass Thermometers
E2251 Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision Liquids
This test method is under the jurisdiction of ASTM Committee D22 on Air Quality and is the direct responsibility of Subcommittee D22.04 on Workplace Air Quality.
Current edition approved Oct. 1, 2015Nov. 15, 2022. Published October 2015January 2023. Originally approved in 1985. Last previous edition approved in 20102015 as
D4532 – 10.D4532 – 15. DOI: 10.1520/D4532-15.10.1520/D4532-22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4532 − 22
2.2 Other International Standards:
ISO GUM Guide to the Expression of Uncertainty in Measurement, ISO Guide 98
ISO 7708 Air Quality—Particle Size Fraction Definitions for Health-Related Sampling
ISO 13137 Workplace Atmospheres – Pumps for Personal Sampling of Chemical and Biological Agents – Requirements and
Test Methods
ISO 15767 Workplace Atmospheres—Controlling and Characterizing Errors in Weighing Collected Aerosol
ISO 18158 Workplace Atmospheres - Terminology
EN 481 Workplace Atmospheres—Size Fraction Definitions for the Measurement of Airborne Particles in the Workplace
EN 13205 Workplace Atmospheres—Assessment of Performance of Instruments for Measurement of Airborne Particle
Concentrations
3. Terminology
3.1 For definitions of terms used in this test method, refer to Terminology D1356.
3.2 Definitions of Terms Specific to This Standard—Standard:(otherwise, consult Terminology D1356):
3.1.1 respirable convention—target specification for sampling instruments when the respirable fraction is the fraction of interest.
3.2.1 respirable fraction—mass fraction of total airborne particles which penetrate to the unciliated airways. (ISO 18158)
3.2.2 respirable sampler—aerosol sampler that is used to collect the respirable fraction of airborne particles according to the
respirable convention (see Terminology D1356) from the surrounding air. (modified from ISO 18158)
3.2.2.1 Discussion—
Fig. 1 shows the collection efficiency of an idealized sampler following the internationally-harmonized sampling conventions of
ISO 7708, EN 481, Guide D6062, and Ref. (1).
NOTE 1—The definition of the respirable fractionconvention is a compromise between previous definitions, available samplers, and the fraction of dust
that penetrates to (rather than deposits in) the alveolar region of the lung. Local legal definitions may differ from the definition adopted in this test method.
3.3 For the terms and definitions related to characterizing uncertainty, see ISO GUM (ISO Guide 98) and Practice D7440.
4. Summary of Test Method
4.1 Air is drawn through a cyclone or equivalent sampler followed by a tared filter, which is then re-weighed to determine the mass
of respirable dust. The air flow rate and time of sampling provide the volume from which the dust mass was sampled. A
time-weighted average respirable dust concentration is calculated by dividing the mass by the total air volume.
FIG. 1 Collection Efficiency of an Ideal Sampler Following the International Sampling Conventions
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
The boldface numbers in parentheses refer to a list of references at the end of this standard.
D4532 − 22
NOTE 2—Samplers alternative to a cyclone (for example, foam-based or personal cascade impactors) may be used if they have desirable properties (for
example, ease of use or uncertainty control) for intended application. are commercially available. Nevertheless, this test method is limited to cyclone
samplers.
5. Significance and Use
5.1 This test method covers the determination of respirable dust concentration in workplace atmospheres.
5.2 Variations of the test method are in world-wide use for determining compliance relative to occupational exposure levels.
5.3 The test method may be used to verify dust control measures.
5.4 The test method may also be applied in research into health effects of dust in an occupational setting.
6. Apparatus
6.1 Sampling Unit—The sampling unit consists of a pump, a sampling head, and tubing connecting the pump and outlet of the
sampling head. The sampling head consists of a cyclone and a filter assembly.
6.1.1 Respirable Dust Cyclone—Various types of respirable dust cyclones are commercially available. In general, these samplers
can be categorized into two groups, high flow rate cyclone samplers (flow rate range 4.24.2 L ⁄min – 1010 L L/min) ⁄min) and
medium flow rate cyclone samplers (flow rate range 1.71.7 L ⁄min – 2.752.75 L L/min). ⁄min). High flow rate samplers should be
considered for workplaces where airborne particle concentrations are low (for example, <0.05 mg/m ) or where it is desirable to
take short-term exposure measurements (for example, <4 hours)h) (2-4).
NOTE 3—Bias relative to the international respirable dust criterion and the dust size distribution being sampled (2-13) must be controlled sufficiently (see
13.2.4) for the application of intended use.
6.1.1.1 Bias relative to the international respirable dust criterion and the dust size distribution being sampled (2-13) must be
controlled sufficiently (see 13.2.4) for the application of intended use.
6.1.2 Filter Cassette Assembly—Filter, filter-support pad, and filter cassette holder with suitable caps. The filter shall be
non-hygroscopic and provide a collection efficiency greater than 95 % for the dust of interest.
NOTE 4—As an example, most glass fiber and membrane filters with nominal pore size of 5 μm will fulfill this requirement (14). PVC is recommended
for gravimetric analysis. The equilibrated filter is preweighed by the user.
6.1.2.1 As an example, most glass fiber and membrane filters with nominal pore size of 5 μm will fulfill this requirement (14).
PVC filters are recommended for gravimetric analysis. The equilibrated filter is preweighed by the user.
NOTE 5—It is preferable to use a conductive cassette because electrostatic charge on the dust and a non-conductive cassette can result in a significant bias
(15-20). For controlling dust which may become attracted to the interior cassette walls, several filter holders equipped with a shielded respirable dust filter
and cassette are commercially available, which may be weighed together with the filter.
6.1.2.2 It is preferable to use a conductive cassette because electrostatic charge on the dust and a non-conductive cassette can result
in a significant bias (15-20). For controlling dust which may become attracted to the interior cassette walls, several filter holders
equipped with a shielded respirable dust filter and cassette are commercially available, which may be weighed together with the
filter.
6.1.3 Personal Sampling Pump—With a flow rate uncertainty (see 13.2.1) less than 5 %. The pump pulsation amplitude may not
exceed 610 % of the mean flow according to ISO 13137 method (21) or 625 % of the mean flow if pump pulsation is measured
at the inlet of the cyclones (22). The nominal sampling flow rate for each cyclone type is adjusted using Practice D5337.
NOTE 3—Cyclone samples collected with pulsating flow have been shown to yield a negative bias as large as 70 % compared to samples collected under
steady flow (22).
D4532 − 22
6.2 Charger—Pump batteries Pumps shall be completely charged with an appropriate charger following the manufacturer’s
instructions or disposable batteries may be used.or with replacement disposable batteries, following manufacturer’s instructions.
6.3 Weighing Room—With temperature (20(20 °C 6 2°C)2 °C) and humidity (50 6 5 % (50 % Relative Humidity (RH) 6 5 %
(RH)) control to allow weighing with an analytical balance to accuracy required. See ISO 15767 and Practice D6552 for
controlling and characterizing errors in weighing collected aerosols.
NOTE 7—If a weighing room is not available, a filter equilibration chamber can be used to equilibrate the filters in a temperature (20 6 2°C) and humidity
(50 6 5 % RH) controlled chamber.
6.3.1 If a weighing room is not available, a filter equilibration chamber can be used to equilibrate the filters in a temperature (20 °C
6 2 °C) and humidity (50 % RH 6 5 % RH) controlled chamber.
6.4 Analytical Balance—Capable of weighing to 0.01 mg or better, depending on application. Particular care must be given to the
proper zeroing of the balance.
6.5 Charge Neutralizer—To eliminate static charge in the balance case and on the filters during weighing. Po-210 neutralizers if
used must be replaced within nine months of their production date.
6.6 Plane-Parallel Press—Capable of giving a force of at least 1000 N (may be required if plastic filter holders are used that must
be pressed together after insertion of the filter).
6.7 Flow Meter—With Measuring volumetric flow with precision equal to 2 % or better within the range of the flow rate used.
Various flow meters are introduced in Practice D5337. Calibration Flow verification of rotameterrotameters can be performed using
Practice D3195.
6.8 Thermometer—Capable of covering the temperature range of interest with divisions every 0.1°C0.1 °C (see Specifications E1
and E2251).
6.9 Flexible Tube with Two Clips—One near the sampling head, if the sampling head does not have a clip, and the other midway
between the sampling head and the pump. The length of the tube is dependent on how the sampling unit is worn. A length of
0.70.7 m to 0.9 m is suitable if the pump is attached to the worker’s belt.
6.10 Forceps—Preferably nylon.
6.11 Rod or filter lifter.
6.12 Petri Dishes or Filter Keepers—With diameter slightly greater than the filter.
6.13 Tape—Adhesive (for example, plastic electrical), for sealing samplers.
7. Preparation of Samplers Prior to Sampling
7.1 Inspect the interior of the cyclone and clean it to keep away from reentrainment ensure no re-entrainment of large particles.
If the inside surfaces are visibly scored, replace the cyclone since the dust separation characteristics of the sampler might be
altered.
7.2 Equilibrate all the filters in an environmentally controlled weighing room or equilibration chamber for at least 24 hours.24 h.
7.3 Weigh the filters in the weighing room.
7.3.1 Internally calibrate the balance (zero balance) before use.
D4532 − 22
7.3.2 Grasp the filter with forceps and pass the filter several times through a charge neutralizer to eliminate static charge, if
necessary.
7.3.3 Record the weight of filters.
7.4 Place the tared filter and filter support in the filter cassette holder, close firmly, and tape the circumference of the filter holder.
holder with adhesive tape. If necessary, use the press described in 6.6.
7.5 Place caps toon the filter holder and suitably cover the assembly to avoid contamination if it is held for any time prior to use.
8. Sampling
8.1 Remove the filter holder caps and connect the filter holder to the cyclone as required by the manufacturer. Connect the outlet
of the sampling head to the calibrated pump’s inlet with a piece of flexible tubing. Make sure all connections are free of leaks by
closing off the filter inlet.
8.2 Attach the sampling head to the worker so that it is located in the breathing zone. The worker’s breathing zone consists of a
hemisphere 30-cm radius extending in front of the face, and measured from a line bisecting the ears. The sampling head shall be
placed in such a manner to prevent dust from falling into it and to avoid restricting the inlet. The pump can be attached to the
worker’s belt.
8.3 Initiate sampling by turning the pump on and record the flow rate and the time. For long-term sampling, periodically check
the pump to determine whether the pump functions properly. If a noticeable change of the flow rate is visually observed due to
bending or blockage of tubing, turn off the pump and reset the flow rate. If unable to reset the flow rate to the original setting,
terminate sampling and note the reason for termination.
NOTE 8—Depending on sample load, consecutive samples over the shift may be required. However, the sampling time should not exceed the operating
life of the batteries or the prevailing “full shift.” The nominal sampling period is eight hours. Sampling times shorter than a full shift are permitted if
the following occurs:
The pressure drop across the filter exceeds the pump’s capabilities; that is, the filter becomes clogged.
Specific working operations of shorter duration are to be investigated.
Determinations of variations of the exposure during a shift are made.
8.3.1 Depending on sample load, consecutive samples over the shift may be required. However, the sampling time should not
exceed the operating life of the batteries or the prevailing “full shift.” The nominal sampling period is eight hours. Sampling times
shorter than a full shift are permitted if the following occurs:
The pressure drop across the filter exceeds the pump’s capabilities; that is, the filter becomes clogged.
Specific working operations of shorter duration (for example, task-based exposures) are to be investigated.
Determinations of variations of the exposure during a shift are made.
8.3.2 The sampler must be observed during sampling to the extent possible in order to ensure that it is not inverted at any time,
otherwise re-deposition of particles from the cyclone body onto the filter may occur. Instances of inversion, whether observed
directly or reported by the person being sampled should be included in the report.
8.4 At the end of the sampling period, turn the pump off and record the final flow rate and time.
8.5 Remove the sampling unit from the worker and carefully take the sampling equipment to a clean, dust-free area.
8.6 Measure the pump flow rate using the calibrated flow meter (see Practice D5337 for the measurement and adjustment of flow
rate). If the flow rates before and after sampling differ by more than 5 %, consider the sample to be invalid.
8.7 Remove the filter holder from the sampling head and replace the filter holder caps.
8.8 For each set of ten or fewer samples, submit a field blank sample. The filters and filter holders to be used as blanks are prepared
and transported in the same manner as the samples except that no air is drawn through them. Label these as blanks.
D4532 − 22
8.9 The filter assembly should be returned to the laboratory in a suitable container designed to prevent sample damage in transit.
NOTE 9—The sampler must not be inverted at any time or else re-deposition of particles from the cyclone body onto the filter may occur.
8.9.1 The preferred procedure is to personally transport samples back to the laboratory such as by car or carry-on aircraft baggage.
If collected samples need to be shipped by a shipping service, place sample packages inside larger boxes and cushion with packing
materials.
NOTE 10—The preferred procedure is to personally transport samples back to the laboratory such as by car or carry-on aircraft baggage. If collected
samples need to be shipped by a shipping service, place sample packages inside larger boxes and cushion with packing materials.
9. Flow Rate Adjustment and Standardization
9.1 Air flow rate adjustment of the sampling unit should be completed before each sampling session. Maint
...