ASTM D6061-96

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
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Designation: D 6061 – 96
Standard Practice for
Evaluating the Performance of Respirable Aerosol
Samplers
This standard is issued under the fixed designation D 6061; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
1.1 This practice covers the evaluation of the performance
of personal samplers of non-fibrous respirable aerosol. The
2. Referenced Documents
samplers are assessed relative to a specific respirable sampling
2.1 ASTM Standards:
convention. The convention is one of several that identify
D 1356 Terminology Relating to Atmospheric Sampling
specific particle size fractions for assessing health effects of
and Analysis
airborne particles and in the setting of and testing for compli-
D 4532 Test Method for Respirable Dust in Workplace
ance with permissible exposure limits in the workplace and
Atmospheres
ambient environment. The conventions, which define inhal-
D 6062M Performance Specifications for Samplers of
able, thoracic, and respirable aerosol sampler ideals, have now
Health-Related Aerosol Fractions
been adopted by the International Standards Organization
2.2 International Standards:
(Technical Report ISO TR 7708), the Comité Européen de
ISO TR 7708 Technical Report on Air Quality—Particle
Normalisation (CEN Standard EN 481), and the American
Size Fraction Definitions for Health-Related Sampling,
Conference of Governmental Industrial Hygienists (ACGIH,
2 Brussels, 1993
Ref (1)), developed (2) in part from health-effects studies
CEN EN 481 Standard on Workplace Atmospheres. Size
reviewed in Ref (3) and in part as a compromise between
Fraction Definitions for the Measurement of Airborne
definitions proposed in Refs (3,4). This practice is specific to
Particles in the Workplace, Brussels, 1993
respirable aerosol sampler evaluation because of simplifying
CEN prEN 1232 Pre-Standard on Workplace Atmospheres.
characteristics particular to this fraction.
Requirements and Test Methods for Pumps used for
1.2 This practice is complimentary to Test Method D 4532,
,
3 4 Personal Sampling of Chemical Agents in the Workplace,
which specifies a particular instrument, the 10-mm cyclone.
Brussels, 1993
The sampler evaluation procedures presented in this practice
2.3 NIOSH Standards:
have been applied in the testing of the 10-mm cyclone as well
4,5
NIOSH Manual of Analytical Methods, 4th ed., Eller, P. M.,
as the Higgins-Dewell cyclone. Details on the evaluation
ed.: Dept. of Health and Human Services, 1994
have been recently published (5-7) and can be incorporated
Criteria for a Recommended Standard, Occupational Expo-
into revisions of Test Method D 4532.
sure to Respirable Coal Mine Dust, NIOSH, 1995
1.3 Units of the International System of Units (SI) are used
throughout this practice and should be regarded as standard.
3. Terminology
1.4 This standard does not purport to address all of the
3.1 Definitions:
safety concerns, if any, associated with its use. It is the
3.1.1 For definitions of terms used in this practice, refer to
responsibility of the user of this standard to establish appro-
Terminology D 1356.
3.1.2 Aerosol fraction sampling conventions have been
presented in Performance Specifications D 6062M. The rel-
This practice is under the jurisdiction of ASTM Committee D-22 on Sampling
evant definitions are repeated here for convenience.
and Analysis of Atmospheres and is the direct responsibility of Subcommittee
D22.04 on Analysis of Workplace Atmospheres. 3.2 Definitions of Terms Specific to This Standard:
Current edition approved Dec. 10, 1996. Published February 1997.
The boldface numbers in parentheses refer to a list of references at the end of
this practice.
Annual Book of ASTM Standards, Vol 11.03.
The sole source of supply of the 10-mm cyclone known to the committee at this
Available from International Organization for Standardization, Caisse Postale
time is Mine Safety Appliances Co., Instrument Div., P.O. Box 427, Pittsburgh, PA
56, CH-1211, Geneva 20, Switzerland.
15230.
Available from CEN Central Secretariat: rue de Stassart 36, B-1050 Brussels,
If you are aware of alternative suppliers, please provide this information to Belgium.
ASTM Headquarters. Your comments will receive careful consideration at a meeting Available from Superintendent of Documents, U.S. Government Printing
of the responsible technical committee, which you may attend. Office, Stock No. 917-011-00000-1, Washington DC 20402.
5 10
The sole source of supply of the Higgins-Dewell cyclone known to the Available from NIOSH Publications, 4676 Columbia Parkway, Cincinnati, OH
committee at this time is BGI Inc., 58 Guinan Street, Waltham, MA 02154. 45226.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
D 6061
3.2.1 aerodynamic diameter, D (μm)—the diameter of a 3.2.5 sampler number s = 1, ., S— a number identifying a
sphere of density, 10 kg/m, with the same stopping time as a particular sampler under evaluation.
particle of interest.
3.2.6 sampling effıciency E (D, Q)—the modeled sampling
S
3.2.2 respirable sampling convention, E —at aerodynamic efficiency of sampler s as a function of aerodynamic diameter
R
diameter D, defined explicitly as a fraction of total airborne
D and flow rate Q (9.1).
aerosol in terms of the cumulative normal function (8) F as 3.2.6.1 model parameters u , where j = 1, ., J—parameters
j
follows:
that specify the function E (D, Q).
S
3.2.7 sampled concentration c —the concentration that
E 5 0.50 ~1 1 exp@20.06 D#! F @ln@D /D#/s # (1) s
R R R
sampler s would give in sampling aerosol of size-distribution
where the indicated constants are D = 4.25 μm and s
R
dC/dD and is given as follows:
R = ln[1.5]. The function F may be approximated using the
‘
algorithm presented in Appendix X1.
c 5 dD E dC / dD (4)
s * s
3.2.2.1 Discussion—The respirable sampling convention,
3.2.8 mean concentration c—the average of c over the
together with earlier definitions, is shown in Fig. 1. This
s
samplers tested.
convention has been adopted by the International Standards
3.2.9 mean bias D—relative to a conventional sampler,
Organization (Technical Report ISO TR 7708), the Comité
defined as follows:
Européen de Normalisation (CEN Standard EN 481), and the
American Conference of Governmental and Industrial Hygien-
D[ ~c 2 c !c (5)
R R
ists (ACGIH, Ref (1)). The definition of respirable aerosol is
3.2.10 The imprecision or relative standard deviation RSD
the basis for the recommended exposure level (REL) of
is defined here in terms of independent analytical, intra-
respirable coal mine dust as promulgated by NIOSH (Criteria
sampler, and inter-sampler components:
for a Recommended Standard, Occupational Exposure to
3.2.10.1 analytical relative standard deviation
Respirable Coal Mine Dust) and also forms the basis of the
RSD —the precision relative to the true respirable con-
analytical
NIOSH sampling method for particulates not otherwise regu-
centration c associated with analysis, for example, the weigh-
R
lated, respirable (NIOSH Manual of Analytical Methods).
ing of filters, analysis of a-quartz, and so forth.
3.2.3 size-distribution dC/dD (mg/m /μm)—of a given air-
3.2.10.2 pump-induced relative standard deviation
borne aerosol, the mass concentration of aerosol per unit
RSD —the intra-sampler imprecision relative to the true
pump
aerodynamic diameter range.
respirable concentration c associated with both drift and
R
3.2.3.1 log-normal size distribution dC /dD—an idealized
ln
variability in the setting of the pump.
distribution characterized by two parameters: the geometric
3.2.10.3 inter-sampler relative standard deviation
standard deviation (GSD) and mass median diameter (MMD).
RSD —the inter-sampler imprecision relative to the true
inter
dC /dD is given explicitly as follows:
ln
respirable concentration c and taken as primarily associated
R
1 C 1
2 2
with physical variations in sampler dimensions.
dC /dD 5 exp 2 ln@D / MMD# /ln@GSD#
F G
ln
D ln@GSD# 2
2p
=
3.2.10.4 The total imprecision RSD is then given as follows:
(2)
2 2 2
RSD 5 RSD 1 RSD 1 RSD (6)
=
analytical pump inter
where C is the total mass concentration.
3.2.4 true respirable concentration c (mg/m )—the con-
R 3.2.11 flow rate Q (L/min)—the flow rate sampled by a
centration measured by a conventional (that is, ideal) respirable
given sampler.
sampler and given in terms of the size distribution dC/dD as
3.2.12 flow number F—the number (for example, 4) of
follows:
sampler flow rates Q tested.
‘
3.2.13 replication number n (for example, 4)— the number
c 5 dD E dC / dD (3)
R * R
of replicate measurements for evaluating a given sampler at
specific flow rate and aerodynamic diameter.
3.2.14 parameter number p = 1, ., P (for example, 4)—a
number identifying parameters u in modeled sampling effi-
p
ciency data as in Section 9.
3.2.15 Accuracy A, Busch probabilistic—the fractional
range, symmetric about the true concentration c , within which
R
95 % of sampler measurements are to be found (9-12 and the
NIOSH Manual of Analytical Methods).
3.2.15.1 Discussion—The function A depends only on the
bias D and total imprecision RSD in the event that these
quantities are independent of c . A is defined implicitly as
R
follows:
F@D1 A!/RSD#2F@~D2 A!/RSD# 5 95 % (7)
where F is the cumulative normal function. The function A
(D, RSD) may be computed numerically and is depicted in Fig.
FIG. 1 Respirable Aerosol Collection Efficiencies 2. Alternatively, Eq 7 has an approximate solution (13) for A[D,
D 6061
RSD —imprecision induced by imprecision in the sam-
pump
pling pump.
ˆ
RSD —estimated inter-sampler imprecision RSD .
inter inter
ˆ
RSD —estimated pump-induced imprecision RSD .
pump pump
s—sampler number.
S—number of samplers evaluated.
t—sampling time.
v (m/s)—wind speed.
D—bias relative to an ideal sampler following the respirable
sampling convention.
D—estimated bias D.
e —random variable contribution to evaluation experi-
eval s
mental error in a concentration estimate.
e —random variable contribution to inter-sampler error in a
s
concentration estimate.
FIG. 2 Contours Showing Accuracy A at 95 % Confidence Level
u—sampling efficiency model parameter.
in Terms of Bias and Relative Standard Deviation (RSD )
s —sampling efficiency model parameter.
s —evaluation experimental standard deviation in a con-
eval
centration estimate.
RSD] given as follows:
s —inter-sampler standard deviation in a concentration
21 21
inter
A@D, RSD#5F ~0.95! 3 RSD 1 Sqrt@~F ~1.95/2!
estimate.
21 2 2 2
2F ~0.95!! RSD 1D # (8)
s —estimate for s .
eval eval
This expression is easily evaluated using a calculator, noting
s —estimate for s .
inter inter
−1 −1
that F (0.95) = 1.645, and F (1.95/2) = 1.960.
s —respirable sampling convention parameter equal to
R
3.3 Symbols and Abbreviations:
ln[1.5].
A—(Busch probabilistic) accuracy as defined in terms of
s —weighing imprecision in mass collected on a filter.
weight
bias and precision (see 3.2.15).
F[x]—cumulative normal function defined, given argument
—estimated accuracy A.
x.
A—95 % confidence level on the (Busch probabilistic)
95 %
4. Summary of Practice
accuracy A.
C (mg/m )—total mass concentration. 4.1 Calm-air Evaluation—The sampling efficiency from
cov —covariance matrix for sampler s and efficiency pa-
D = 0 to 10 μm and its variability are measured in calm air
s ij
rameters u and u . (<0.5 m/s) for several candidate samplers operated at a variety
i j
c (mg/m )—concentration measured by a conventional (that of flow rates. This information is then used to compute
R
is, ideal) respirable sampler. concentration estimates expected in sampling representative
cˆ—sampler-averaged concentration estimate. log-normal aerosol size distributions. Precision and bias (4.1.1
cˆ —concentration estimate from sampler s. and 4.1.2) are therefrom determined relative to a conventional
s
D (μm)—aerosol aerodynamic diameter. sampler. Overall performance in calm air can then be assessed
D —sampling efficiency model parameter. by computing a confidence limit on the Busch probabilistic
D (μm)—respirable sampling convention parameter equal to accuracy, accounting for uncertainty in the evaluation experi-
R
4.25 μm in the case of healthy adults, or 2.5 μm for the sick or ment, given measured bias and imprecision at each log-normal
infirm or children. aerosol size distribution of interest. This test has evolved from
E—sampling convention in general. work described in Refs (14-21).
E —respirable sampling convention. 4.1.1 Precision—In the sampling of aerosol, several com-
R
E —sampling efficiency of sampler s. ponents of precision have been found (5) significant. These
s
F—number of flow rates evaluated. include inter-sampler variability, caused by physical variations
GSD—geometric standard deviation of a representative in the samplers; intra-sampler variability, from inaccuracy in
log-normal aerosol size distribution. the setting and maintenance of required airflow; and analytical
MMD—mass median diameter of a representative log-
error, for example, in the weighing of filters, or, as another
normal aerosol size distribution. example, in the measurement of a-quartz.
n—number of replicate measurements.
4.1.2 Bias—As no real sampler follows the aerosol fraction
P—number of sampling efficiency parameters. conventions exactly, bias always exists between true and
Q (L/min)—sampler flow rate. conventional (ideal) samplers. This bias depends on the par-
RSD—relative standard deviation (relative to true concen- ticle size-distribution of the aerosol sampled. The worst-case
tration as estimated by an ideal sampler following the respi- situation is in the sampling of monodisperse aerosol. However,
rable sampling convention). in most workplaces, aerosol is present in a broad distribution of
RSD —analytical imprecision component. sizes. The cancellation of positive and negative components of
analytical
RSD —uncertainty in the pump flow rate. bias at different particle sizes reduces the overall bias in this
flow
RSD —inter-sampler imprecision. case.
inter
D 6061
5. Significance and Use 7.1.2 Standard Polystyrene Latex Spheres for calibrating
APS (6.2).
5.1 This practice is significant in providing the experimental
7.2 Materials:
means for replacing instrument or sampler specification by
7.2.1 Five-micrometre PVC Membrane Filters and Conduc-
p
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