ASTM E1645-94

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
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Designation: E 1645 – 94 An American National Standard
Standard Practice for
the Preparation of Dried Paint Samples for Subsequent
Lead Analysis by Atomic Sprectrometry
This standard is issued under the fixed designation E 1645; 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 Cadmium, and Cobalt in Paint by Atomic Absorption
Spectroscopy
1.1 This practice covers the sample preparation procedures
E 1605 Terminology Relating to Abatement of Hazards
for paint samples that are collected during the assessment or
from Lead-Based Paint in Buildings and Related Struc-
abatement of lead hazards in and around buildings and related
tures
structures.
2.2 Other Documents:
1.2 This practice describes the digestion procedures for
Environmental Protection Agency, Standard Operating Pro-
paint samples that are to be analyzed for lead content.
cedures for Lead in Paint by Hotplate- or Microwave-
1.3 This practice covers the general considerations for
based Acid Digestions and Atomic Absorption or Induc-
quantitative sample extraction for total recoverable lead in
tively Coupled Plasma Emission Spectrometry; U.S. EPA,
dried paint samples (either bulk paint or paint powder) using
Research Triangle Park, NC (1991).
hot plate or microwave heating techniques, or both.
NIOSH Manual of Analytical Methods, P.M. Eller, Ed., 3rd
1.4 The values stated in SI units are to be regarded as the
ed., Methods 7082 and 7300; National Institute for Occu-
standard.
pational Safety & Health, Cincinnati, OH (1984).
1.5 This practice describes an alternative sample prepara-
tion procedure to that given in Test Method D 3335. The
3. Terminology
procedure described in this practice is a wet digestion method,
3.1 Definitions—For definitions of terms relating to the
while that described in Test Method D 3335 employs dry
preparation of dried paint samples that are not given here, refer
ashing. Also, unlike the procedure outlined in Test Method
to Terminology D 1129, Terminology E 1605, or Test Method
D 3335, this practice includes a microwave digestion proce-
D 3335.
dure for dried paint samples.
3.1.1 batch—a group of field or quality control samples that
1.6 This practice contains notes that are explanatory and not
are processed together using the same reagents and equipment.
part of the mandatory requirements of the standard.
3.1.2 digestate—an acidified aqueous solution that results
1.7 This practice is based on two NIOSH Methods, 7082
from digestion of the sample.
and 7105, and on EPA standard operating procedure for lead in
3.1.3 digestion—the sample preparation process that solu-
paint.
bilizes (extracts) targeted analytes present in the sample, and
1.8 This standard does not purport to address all of the
results in an acidified aqueous solution called the digestate.
safety concerns, if any, associated with its use. It is the
3.1.4 extraction—the dissolution of target analytes from a
responsibility of the user of this standard to establish appro-
solid source matrix into a liquid form. During sample diges-
priate safety and health practices and determine the applica-
tion, target analytes are extracted (solubilized) into an acid
bility of regulatory limitations prior to use. For specific
solution.
precautionary statements, see 6.2.4.4 and 7.2.1.1.
3.1.5 method blank—a sample, devoid of analyte, that is
2. Referenced Documents analyzed to determine its contribution to the total blank
(background) reading.
2.1 ASTM Standards:
3.1.6 non-spiked sample—a sample, devoid of analyte, that
D 1129 Terminology Relating to Water
2 is targeted for addition of analyte but is not fortified with all
D 1193 Specification for Reagent Water
target analytes prior to sample preparation.
D 3335 Test Method for Low Concentrations of Lead,
3.1.6.1 Discussion—Analysis results for this sample are
used to correct for background levels in the blank medium that
is used for spiked and spiked duplicate samples.
This practice is under the jurisdiction of ASTM Committee E-6 on Performance
of Buildings and is the direct responsibility of Subcommittee E06.23 on Lead Paint
Annual Book of ASTM Standards, Vol 06.01.
Abatement.
Annual Book of ASTM Standards, Vol 04.11.
Current edition approved Dec. 15, 1994. Published February 1995.
Available from National Technical Information Service, 5285 Port Royal Rd.,
Annual Book of ASTM Standards, Vol 11.01.
Springfield, VA 22161.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
E 1645
hot spots common to electric hot plates.
3.1.7 reagent blank—a digestate that reflects the maximum
treatment given any one sample within a batch of samples,
6.1.2 (Alternatively) Microwave Digestion System, nominal
except that it has no sample placed initially into the digestion
550 W power minimum, with turntable, 120-mL TFE-
vessel. (The same reagents and processing conditions that are
fluorocarbon-lined vessels and capping station. The power
applied to field samples within a batch are also applied to the
available for heating must be evaluated weekly in order to
reagent blank.)
ensure that the microwave unit has not degraded, and to
3.1.7.1 Discussion—Analysis results from this sample pro-
compare absolute power settings for different microwave
vide information on the level of potential contamination
digestion apparatuses. (See Annex A1 for information on
resulting from only laboratory sources that are experienced by
evaluation and calibration of microwave power level.)
samples processed within the batch.
6.2 Reagents, Glassware and Supplies:
3.1.8 reference material (standard reference material)
6.2.1 Apparatus-Hot Plate Digestion:
(SRM)—a material of known composition where the lead level
6.2.1.1 Borosilicate glass beakers, 125-mL or 50-mL with
is certified by the manufacturer.
watchglass covers,
3.1.9 sample set—a group of samples (one or more).
6.2.1.2 Class A borosilicate volumetric flasks, 100 mL and
3.1.10 spiked sample or spiked duplicate sample—a blank
200 mL,
medium that contains no purposely added analyte to which a
6.2.1.3 Class A borosilicate volumetric pipets, volume as
known amount of analyte is added before preparation.
needed,
3.1.10.1 Discussion—Analysis results for these samples are
6.2.1.4 Linear polyethylene bottles with caps, 100 mL,
used to provide information on the precision and accuracy of
6.2.1.5 Analytical balance, accurate to 60.0001 g,
the overall process.
6.2.1.6 Glass funnels, and
6.2.1.7 Filter paper.
4. Summary of Practice
6.2.2 Apparatus-Microwave Digestion:
4.1 Lead in dried paint samples (chips, powder, etc.) is
6.2.2.1 Centrifuge, with 30 mL polysulfone centrifuge tubes
solubilized (extracted) by digestion with nitric acid and hydro-
and polypropylene screw closure,
gen peroxide facilitated by heat, or by a mixture of nitric acid
6.2.2.2 Class A volumetric and graduated pipets,
and hydrochloric acid facilitated by microwave energy. The
6.2.2.3 Mechanical shaker, and
lead content of the digested sample is then in a form ready for
6.2.2.4 Analytical balance, accurate to 60.0001 g.
measurement by atomic spectrometric methods.
6.2.3 Reagents-Hot Plate Digestion:
6.2.3.1 Concentrated nitric acid, ACS reagent grade or
5. Significance and Use
spectrographic grade 16.0 M HNO ,
5.1 Paint in buildings and related structures needs to be
6.2.3.2 Nitric acid, 10 % (w/v): Add 100 mL concentrated
monitored for lead content in order to determine the potential
HNO to 500 mL ASTM Type I or Type II water (see
lead hazard. Hence, effective and efficient methods are required
Specification D 1193). Dilute to 1 L with ASTM Type I or Type
for the preparation of paint samples that may contain lead.
II water,
5.2 This practice is to be used for the digestion of paint
6.2.3.3 Hydrogen peroxide,30% H O (w/w); ACS reagent
2 2
samples that are collected during various construction and
grade, and
renovation activities associated with lead abatement in and
6.2.3.4 ASTM Type I or Type II water (see Specification
around buildings and related structures. This practice may be
D 1193).
used for the preparation of paint samples collected in other
6.2.4 Reagents-Microwave Digestion:
environments as well.
6.2.4.1 Concentrated nitric acid, ACS reagent grade or
5.3 This practice may be used to prepare samples that have
spectrographic grade 16.0 M HNO ,
been obtained in order to ensure compliance with federal laws
6.2.4.2 Concentrated hydrochloric acid, ACS reagent grade
that govern lead content in paints.
12.3 M HCl,
5.4 This practice may be used to prepare samples that have
6.2.4.3 ASTM Type I or Type II water (see Specification
been collected for risk assessment purposes.
D 1193), and
5.5 This practice is intended for use with paint samples that
6.2.4.4 Extraction Solution—In a 1-L volumetric flask,
are prepared for subsequent analysis by laboratory-based
combine the following in order and mix well: 500 mL ASTM
quantitative analytical methods.
Type I or Type II water, 60 mL concentrated HNO and 180 mL
concentrated HCl. Cool to room temperature and dilute to 1 L
6. Apparatus
with ASTM Type I or Type II water. Caution: Nitric and
6.1 Heating Equipment:
hydrochloric acid fumes are toxic. Prepare in a well-ventilated
6.1.1 Electric Hot Plate—suitable for operation at surface
fume hood.
temperatures up to at least 140°C. A temperature of at least
7. Sample Treatment
100°C, as measured by a thermometer placed inside a boro-
silicate glass container (on the hot plate) filled with digestion
7.1 Sample Preparation:
solution, should be attainable. (See Note 1.)
7.1.1 Sample Mass and Area—After analysis, report the
final results in area concentration (mg Pb/cm ) or mass
NOTE 1—Provided that the hot plate is capable of handling the extra
concentration (ppm Pb, percent Pb by mass, or alternative
heating required, use of a 12 to 25-mm (approximately 0.5 to 1-in.) thick
aluminum plate placed on the burner head can help reduce the presence of units). If area concentration is desired, sample areas must be
E 1645
provided (by the person submitting the samples) for each paint total (sample plus plastic bag) to the nearest 0.1 mg. This mass
sample (chip, powder, etc.). The mass of area concentration is the total container plus sample mass. This is performed while
samples must be determined and processed in total; mass wearing clean vinyl gloves prior to homogenization (grinding).
concentration samples may be subsampled (after grinding and (2) Transfer the collected paint sample into a clean, labeled
homogenization), depending on the sample mass.
container such as a beaker or plastic centrifuge tube. Transfer
as much of the paint sample as possible to the container by
7.1.2 Area Samples—For each field sample, homogenize the
dried paint sample (inside the original sample container, if carefully tapping or by using a clean spatula (or rubber
policeman). Any visible traces of paint left in the original
possible) as described in the following:
container may result in bias of final lead analysis results. In
7.1.2.1 Don a new clean pair of vinyl gloves to perform
general, most losses caused by fine powder remaining in the
sample handling.
original container will not result in any significant bias
7.1.2.2 Remove any large amounts of substrate present in
(particularly with respect to the large sampling variability that
the sample. Exercise care when removing substrate to avoid
normally accompanies the field collection practices). However,
any losses of paint. If required, use a clean safety razor blade
any visible material that can not be transferred should be
or equivalent tool to aid in substrate removal.
documented in sample preparation records.
7.1.2.3 Determination of Total Collected Sample Mass—
(3) Re-determine the mass of the empty plastic bag. This
This determination is most accurate when the sample has been
mass is the empty container mass.
collected in a rigid-walled sampling container. Determinations
(4) Determine the total sample mass by subtracting the
of total sample mass for samples collected in plastic bags are
empty container mass from the total container plus sample
less accurate due to difficulties with complete removal of the
mass.
sample from the container. However, procedures for this
7.1.2.4 Homogenization of Samples—Breakup the paint
determination for samples collected in both these types of
sample into small pieces using a clean sharp blade, or by
containers is presented because of limits in laboratory control
crushing with a clean plastic or glass rod. Sample should be
over field collection activities. Use the following procedure to
broken down to a fine powder. Use of a mortar and pestle or
determine total collected sample mass for samples collected in
other grinding device may be needed to achieve a fine powder.
rigid walled containers:
Other techniques, for example, the use of dry ice to assist in the
(1) Label the original sample container cap to match that of
breakup of the sample, may also be employed.
the container body using indelible ink and allow the ink to dry.
7.1.2.5 Hot Plate Digestions—Determine the mass, to the
This is performed to avoid errors in determing mass resulting
nearest 0.1 mg, of a 0.25 to 0.50 g subsample of the
from a mismatch of caps to container bodies.
homogenized sample into a clean, labeled 125-mL or 50-mL
(2) Determine the mass of the area concentration sample in
beaker.
total (sample plus original container with cap) to the nearest
7.1.2.6 Microwave Digestions—Determine the mass, to the
0.1 mg. This mass is the total container plus sample mass. This
nearest 0.1 mg, of a 0.1 to 0.2 g subsample of the homogenized
is performed while wearing clean vinyl gloves prior to homog-
sample into a clean, labeled 30-mL polysulfone centrifuge
enization (grinding).
tube.
(3) Transfer the collected paint sample into a clean, labeled
7.1.3 Mass Samples—For each field sample, perform the
container such as a beaker or plastic centrifuge tube. Transfer
homogenization and subsample mass determining steps using
as much of the paint sample as possible to the container by
the same general procedure described for the area samples
carefully tapping or by using a clean spatula (or rubber
(7.1.2.1, 7.1.2.2, 7.1.2.4, 7.1.2.5 and 7.1.2.6). If possible,
policeman). Any visible traces of paint left in the original
perform the homogenization in the original sample container. If
container may result in bias of final lead analysis results. In
not, include the performance of the transfer
...