ASTM E1979-12(2016)
(Practice)Standard Practice for Ultrasonic Extraction of Paint, Dust, Soil, and Air Samples for Subsequent Determination of Lead
Standard Practice for Ultrasonic Extraction of Paint, Dust, Soil, and Air Samples for Subsequent Determination of Lead
SIGNIFICANCE AND USE
5.1 Ultrasonic extraction using dilute nitric acid is a simpler and easier method for extracting lead from environmental samples than are traditional digestion methods that employ hot plate or microwave digestion with concentrated acids (1), (3), (5), (6). Hence, ultrasonic extraction may be used in lieu of the more rigorous strong acid/high temperature digestion methods (for example, see Ref (1) and Test Method E1613), provided that the performance is demonstrated using accepted criteria as delineated in Guide E1775.
5.2 In contrast with hot plate or microwave digestion techniques, ultrasonic extraction is field-portable, which allows for on-site sample analysis.
SCOPE
1.1 This practice covers an ultrasonic extraction procedure for the extraction of lead from environmental samples of interest in lead abatement and renovation (or related) work, for analytical purposes.
1.2 Environmental matrices of concern include dry paint films, settled dusts, soils, and air particulates.
1.3 Samples subjected to ultrasonic extraction are prepared for subsequent determination of lead by laboratory analytical methods.
1.4 This practice includes, where applicable, descriptions of procedures for sample homogenization and weighing prior to ultrasonic extraction.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 This practice 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 practice to establish appropriate safety and health practices and determine the applicability of regulatory limitation prior to use.
General Information
Relations
Buy Standard
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: E1979 − 12 (Reapproved 2016)
Standard Practice for
Ultrasonic Extraction of Paint, Dust, Soil, and Air Samples
for Subsequent Determination of Lead
This standard is issued under the fixed designation E1979; 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 vacuum Sampling for Subsequent Metals Determination
E631 Terminology of Building Constructions
1.1 This practice covers an ultrasonic extraction procedure
E1605 Terminology Relating to Lead in Buildings
for the extraction of lead from environmental samples of
E1613 Test Method for Determination of Lead by Induc-
interest in lead abatement and renovation (or related) work, for
tively Coupled Plasma Atomic Emission Spectrometry
analytical purposes.
(ICP-AES), Flame Atomic Absorption Spectrometry
1.2 Environmental matrices of concern include dry paint
(FAAS), or Graphite Furnace Atomic Absorption Spec-
films, settled dusts, soils, and air particulates.
trometry (GFAAS) Techniques
1.3 Samples subjected to ultrasonic extraction are prepared E1726 Practice for Preparation of Soil Samples by Hotplate
Digestion for Subsequent Lead Analysis
for subsequent determination of lead by laboratory analytical
methods. E1727 Practice for Field Collection of Soil Samples for
Subsequent Lead Determination
1.4 This practice includes, where applicable, descriptions of
E1728 PracticeforCollectionofSettledDustSamplesUsing
procedures for sample homogenization and weighing prior to
Wipe Sampling Methods for Subsequent Lead Determi-
ultrasonic extraction.
nation
1.5 The values stated in SI units are to be regarded as
E1729 Practice for Field Collection of Dried Paint Samples
standard. No other units of measurement are included in this
for Subsequent Lead Determination
standard.
E1775 Guide for Evaluating Performance of On-Site Extrac-
1.6 This practice does not purport to address all of the tion and Field-Portable Electrochemical or Spectrophoto-
safety concerns, if any, associated with its use. It is the metric Analysis for Lead
responsibility of the user of this practice to establish appro- E1792 Specification for Wipe Sampling Materials for Lead
priate safety and health practices and determine the applica- in Surface Dust
bility of regulatory limitation prior to use.
3. Terminology
2. Referenced Documents
3.1 Definitions: For definitions of terms relating to this
2 practice that do not appear in this section, refer to Terminolo-
2.1 ASTM Standards:
gies E631 and E1605.
D1193 Specification for Reagent Water
3.1.1 extraction—the dissolution of target analytes from a
D5438 Practice for Collection of Floor Dust for Chemical
solid matrix into a liquid form.
Analysis
3.1.1.1 Discussion—During sample digestion or extraction,
D6785 Test Method for Determination of Lead inWorkplace
target analytes are extracted (solubilized) into solution to
Air Using Flame or Graphite Furnace Atomic Absorption
enable subsequent determination by analytical techniques (for
Spectrometry
example, see Test Method E1613).
D7144 Practice for Collection of Surface Dust by Micro-
3.1.2 ultrasonic extraction—the use of ultrasonic energy
and acidic or basic solution to extract targeted analytes from
This practice is under the jurisdiction of ASTM Committee E06 on Perfor-
samples.
manceofBuildingsandisthedirectresponsibilityofSubcommitteeE06.23onLead
3.1.2.1 Discussion—The extract solution is subsequently
Hazards Associated with Buildings.
analyzed for the determination of targeted analytes.
Current edition approved Oct. 1, 2016. Published October 2016. Formerly PS
87–97. Originally adopted by Committee E06 in 1998. Last previous edition
4. Summary of Practice
approved in 2012 as E1979-12. DOI: 10.1520/E1979-12R16.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
4.1 Samples of paint, settled dust (wipe or vacuum), soil, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
airborne particles, obtained byASTM sample collection meth-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. ods (see Practice E1729; Practice E1728, Practice D5438 and
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1979 − 12 (2016)
NOTE 1—Precision digital mechanical pipettors using replaceable tips
Practice D7144; Practice E1727, respectively), are subjected to
meet Class A requirements.
ultrasonic extraction in dilute nitric acid for a delineated time
period. 6.11 Laboratory Wipes, wet or dry, or both.
4.2 Paint samples are ground, homogenized and weighed, if 6.12 Power Source for Sonicator.
necessary, prior to ultrasonic extraction.
6.13 Sieves, Number 10 (1.9 mm) and 250 µm.
4.3 Soil and bulk dust vacuum samples are sieved,
6.14 Collection Tray.
homogenized, and weighed prior to ultrasonic extraction.
6.15 Rubber Mallet.
4.4 If applicable, dust filter samples are weighed prior to
6.16 Nylon Brush.
ultrasonic extraction.
6.17 Aluminum Pie Tins.
4.5 Sample extracts are diluted with ASTM Type I water
(see Specification D1193) in preparation for subsequent deter-
6.18 Dust Mask.
mination of lead by analytical techniques (for example Test
6.19 Glass or Plastic Stirring Rods.
Method E1613, Guide E1775, and NIOSH methods 7082,
6.20 Aluminum Foil (conventional thickness for household
7105, and 7300 (1) ).
use, that is, not heavy duty).
4.6 This practice was developed based on an EPA standard
6.21 Graphite Pencil.
operating procedure (ultrasonic extraction followed by colori-
metric lead analysis (2)) and published protocols (ultrasonic
7. Reagents
extraction followed by anodic stripping voltammetric determi-
nation of lead) (3)(4).
7.1 ASTM Type I Water, in accordance with Specification
D1193.
5. Significance and Use
NOTE 2—Commercially available distilled or deionized water meets
5.1 Ultrasonic extraction using dilute nitric acid is a simpler
ASTM Type I water specifications.
and easier method for extracting lead from environmental
7.2 Extraction Solution, 10 % or 25 % v/v HNO /H O;
3 2
samples than are traditional digestion methods that employ hot
prepared from reagent grade concentrated nitric acid (70 to
plate or microwave digestion with concentrated acids (1), (3),
71 % HNO ) and ASTM Type I water.
(5), (6). Hence, ultrasonic extraction may be used in lieu of the
more rigorous strong acid/high temperature digestion methods
NOTE 3—Air filter samples require 10 % nitric acid (v/v) for extraction,
while all other sample matrices require 25 % v/v HNO /H O.
(for example, see Ref (1) and Test Method E1613), provided
3 2
that the performance is demonstrated using accepted criteria as
8. Procedure
delineated in Guide E1775.
8.1 Testing of Sonicator:
5.2 In contrast with hot plate or microwave digestion
8.1.1 Before use, ensure proper operation of the sonicator
techniques,ultrasonicextractionisfield-portable,whichallows
by employing the following diagnostic test.
for on-site sample analysis.
8.1.1.1 Turn on the sonicator and allow for a reasonable
6. Apparatus and Materials
warm-up period, as recommended by the instrument manufac-
turer.
6.1 Sonicator, 50 W minimum power; proper operation of
the sonicator shall be confirmed prior to initial use and 8.1.1.2 Insert the tip of a graphite pencil into the bath.
8.1.1.3 If the sonication device is operating properly, graph-
periodically thereafter.
ite in solution will be observed streaming off the tip of the
6.2 Plastic Centrifuge Tubes, 50 mL, with screw caps.
pencil.
6.3 Analytical Balance, accuracy better than or equal to
8.1.2 Alternatively, demonstrate proper operation of the
60.002 g.
sonicator according to the following procedure:
8.1.2.1 Fillthesonicatorbathwithwarmwater(ca.45°C)to
6.4 Mortar and Pestle, pug mill, or wigglebug.
a level about half-full, and add a small amount (for example,
6.5 Dry Ice (CO (s)).
three drops) of surfactant
6.6 Cooler, for storage of dry ice.
8.1.2.2 Turn on the sonicator for a minimum of 5 min to
degas the solution. Turn off the sonicator.
6.7 Plastic or Glass Rods, 0.6 to 1.0 cm diameter,
8.1.2.3 Place aluminum foil (that is cut to a size conforming
15 to 20 cm length; tapered at one end to conform to the shape
1 3
to ⁄2 to ⁄4 of the area of the bottom of the sonicator bath) on
of the bottoms of the 50 mL centrifuge tubes.
the bottom of the sonicator bath. Lower the foil at an angle to
6.8 Powderless Plastic Gloves.
prevent the trapping of air beneath the foil. Ensure that a
6.9 Tweezers.
narrow layer of solution remains between the foil and the
bottom of the sonicator bath. The foil shall be parallel and
6.10 Class A Pipets, 5 or 10 mL or both, and other volumes
centered to the bottom of the sonicator.
as needed.
8.1.2.4 Turn on the sonicator for a period of 45 s.
8.1.2.5 Examinethealuminumfoilaftersonication.Thefoil
The boldface numbers given in parentheses refer to a list of references at the
end of the text. should be observed to contain a myriad of small holes and
E1979 − 12 (2016)
bumps, and may be torn apart. Also, the perforation observed be weighed. However, the entire ground and homogenized
should be uniform; that is, all portions of the foil should be sample must be placed in the tube for extraction as described
observed to have a high density of holes and perhaps tears. If below.
the foil is not affected in this manner, then the sonicator 8.2.5 Place the sample in a clean, dry, labeled 50 mL
performance is inadequate for the purposes of this practice.
polypropylene centrifuge tube. To ensure quantitative sample
transfer, rinse materials used for transferring samples with a
8.2 Dry Paint Film Samples:
minimum of dilute (5 %) nitric acid, and direct the rinsate into
NOTE 4—This practice assumes paint samples collected in accordance the centrifuge tube.
with Practice E1729.
8.2.6 Using a class A pipet, introduce 5 mL of 25 % HNO
to the centrifuge tube containing the ground and homogenized
8.2.1 Don a pair of gloves.
paint sample. Shake the centrifuge tube briefly to ensure that
8.2.1.1 Ifthedesiredreportedleadconcentrationunitsareto
no solid paint material remains stuck to the bottom of the tube.
be in terms of lead mass per unit area of sample, and the
Rinse the inside of the centrifuge tube with a minimum
estimated sample mass is greater than or equal to 0.25 g, then
quantity of 5 % HNO in order to ensure immersion of all solid
quantitatively transfer the entire sample to an analytical bal- 3
material.
ance and weigh to the nearest 60.002 g. Under these
8.2.7 Cap the centrifuge tube, and place in an upright
circumstances, do quantitative transfer and sample weighing
position in the sonicator bath.
prior to grinding and homogenization as described later in this
8.2.8 Ensure that the bath of the sonicator contains enough
practice.
water so that the water level is at least 2.5 cm above the level
8.2.1.2 If the desired reporting units of lead concentration
of liquid within the centrifuge tube.
are to be in terms of lead mass per unit mass of sample, or if
8.2.9 Repeat steps 8.2.1 – 8.2.8 as needed, depending on the
the desired reporting units are to be in terms of lead mass per
size of the ultrasonic bath and the number of samples.
unit area and the estimated mass of the sample is less than 0.25
g, then quantitatively transfer the sample to a mortar and pestle
NOTE 7—Depending on the size of the sonicator, many centrifuge tubes
or a labeled 50 mL centrifuge tube. Use tweezers if necessary
may be immersed in the bath at one time.Acustom rack for the centrifuge
for quantitative sample transfer. Clean tweezers before and tubesmaybepurchasedorconstructedtoallowfortheregularandorderly
placement of multiple tubes in the sonicator bath.
after use with laboratory wipes.
8.2.2 Sample Grinding and Homogenization:
8.2.10 Apply ultrasonic energy to the crushed and acidified
samples within the immersed centrifuge tubes for at least
8.2.2.1 Grind and homogenize paint film sample to a fine
30 min.
powder using a mortar and pestle, pug mill, or wigglebug.
Quantitatively transfer the ground and homogenized a paint 8.2.11 Remove centrifuge tubes from the bath. Keep tubes
sample to a weighing vessel or weighing paper (see below). in upright position.
Thoroughly clean mortar and pestle, wigglebug, or pug mill 8.2.12 Remove caps from centrifuge tubes that contain
with moistened laboratory wipes prior to and following
samples that were subjected to ultrasonic agitation, and dilute
grinding, and then dry. acidified extracts to the 50 mL mark withASTM Type I water.
8.2.13 Re-cap and then shake the tubes for 5 to 10 s, and
8.2.2.2 Alternatively, place paint film sample in a clean, dry
50 mL centrifuge tube, and place the tube in dry ice. Using a allow the contents to settle. The samples are now ready for
plastic or metal rod, grind and homogenize the super-cooled, analysis for lead content.
brittle paint sample to a fine powder. Thoroughly clean rod
NOTE 8—The sample solutions may require filtration or centrifugation
with laboratory wipes prior to and following grinding proce-
prior to analysis.
dure. Avoid condensation of water onto the sample by sealing
8.3 Settled Dust Wipe Samples:
the sample and allowing it to warm to ambient temperature
before weighing.
NOTE 9—This procedure assumes dust wipe samples were collected in
accordance with Practice E1728 using wipes that conform to Specification
NOTE 5—The use of dry ice as described assists greatly in the grinding
E1792.
and homogenization of dry paint film samples.
8.3.1 Don a pair of gloves.
8.2.3 If the total sample mass is greater than or equal to
8.3.2 If not already placed in a labeled 50 mL centrifuge
0.25 g, or if the total sample mass is less than 0.25 g and the
tube, remove the wipe sample from the sample container with
desired reported lead concentration is to be in units of mass of
a pair of clean tweezers, and place it in a labeled clean and dry
lead per unit mass of sample, weigh 0.05 to 0.25 g of ground
50 mL centrifuge tube. Shove the wipe to the bottom of the
and homogenized paint sample to the nearest 60.002 g, and
tube with a clean glass or plastic rod. Rinse the original sample
record the sample mass.
container (if applicable), tweezers and rod with a minimum of
dilute (5 %) nitric acid to ensure quantitative sample transfer;
NOTE 6—If the desired reporting units are to be in terms of mass of lead
per unit area of sample, and the sample mass is estimated to be less than make sure that the rinsate falls into the centri
...
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: E1979 − 12 E1979 − 12 (Reapproved 2016)
Standard Practice for
Ultrasonic Extraction of Paint, Dust, Soil, and Air Samples
for Subsequent Determination of Lead
This standard is issued under the fixed designation E1979; 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 practice covers an ultrasonic extraction procedure for the extraction of lead from environmental samples of interest in
lead abatement and renovation (or related) work, for analytical purposes.
1.2 Environmental matrices of concern include dry paint films, settled dusts, soils, and air particulates.
1.3 Samples subjected to ultrasonic extraction are prepared for subsequent determination of lead by laboratory analytical
methods.
1.4 This practice includes, where applicable, descriptions of procedures for sample homogenization and weighing prior to
ultrasonic extraction.
1.5 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.
1.6 This practice 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 practice to establish appropriate safety and health practices and determine the applicability of regulatory
limitation prior to use.
2. Referenced Documents
2.1 ASTM Standards:
D1193 Specification for Reagent Water
D5438 Practice for Collection of Floor Dust for Chemical Analysis
D6785 Test Method for Determination of Lead in Workplace Air Using Flame or Graphite Furnace Atomic Absorption
Spectrometry
D7144 Practice for Collection of Surface Dust by Micro-vacuum Sampling for Subsequent Metals Determination
E631 Terminology of Building Constructions
E1605 Terminology Relating to Lead in Buildings
E1613 Test Method for Determination of Lead by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES),
Flame Atomic Absorption Spectrometry (FAAS), or Graphite Furnace Atomic Absorption Spectrometry (GFAAS) Techniques
E1726 Practice for Preparation of Soil Samples by Hotplate Digestion for Subsequent Lead Analysis
E1727 Practice for Field Collection of Soil Samples for Subsequent Lead Determination
E1728 Practice for Collection of Settled Dust Samples Using Wipe Sampling Methods for Subsequent Lead Determination
E1729 Practice for Field Collection of Dried Paint Samples for Subsequent Lead Determination
E1775 Guide for Evaluating Performance of On-Site Extraction and Field-Portable Electrochemical or Spectrophotometric
Analysis for Lead
E1792 Specification for Wipe Sampling Materials for Lead in Surface Dust
3. Terminology
3.1 Definitions: For definitions of terms relating to this practice that do not appear in this section, refer to Terminologies E631
and E1605.
This practice is under the jurisdiction of ASTM Committee E06 on Performance of Buildings and is the direct responsibility of Subcommittee E06.23 on Lead Hazards
Associated with Buildings.
Current edition approved July 15, 2012Oct. 1, 2016. Published August 2012October 2016. Formerly PS 87–97. Originally adopted by Committee E06 in 1998. Last
previous edition approved in 20042012 as E1979 – 04.E1979-12. DOI: 10.1520/E1979-12.10.1520/E1979-12R16.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. 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
E1979 − 12 (2016)
3.1.1 extraction—the dissolution of target analytes from a solid matrix into a liquid form.
3.1.1.1 Discussion—
During sample digestion or extraction, target analytes are extracted (solubilized) into solution to enable subsequent determination
by analytical techniques (for example, see Test Method E1613).
3.1.2 ultrasonic extraction—the use of ultrasonic energy and acidic or basic solution to extract targeted analytes from samples.
3.1.2.1 Discussion—
The extract solution is subsequently analyzed for the determination of targeted analytes.
4. Summary of Practice
4.1 Samples of paint, settled dust (wipe or vacuum), soil, or airborne particles, obtained by ASTM sample collection methods
(see SpecificationPractice E1729; Practice E1728, Practice D5438 and Practice D7144; Practice E1727, respectively), are subjected
to ultrasonic extraction in dilute nitric acid for a delineated time period.
4.2 Paint samples are ground, homogenized and weighed, if necessary, prior to ultrasonic extraction.
4.3 Soil and bulk dust vacuum samples are sieved, homogenized, and weighed prior to ultrasonic extraction.
4.4 If applicable, dust filter samples are weighed prior to ultrasonic extraction.
4.5 Sample extracts are diluted with ASTM Type I water (see Specification D1193) in preparation for subsequent determination
of lead by analytical techniques (for example Test Method E1613, Guide E1775, and NIOSH methods 7082, 7105, and 7300 (1) ).
4.6 This practice was developed based on an EPA standard operating procedure (ultrasonic extraction followed by colorimetric
lead analysis (2)) and published protocols (ultrasonic extraction followed by anodic stripping voltammetric determination of lead)
(3) (4).
5. Significance and Use
5.1 Ultrasonic extraction using dilute nitric acid is a simpler and easier method for extracting lead from environmental samples
than are traditional digestion methods that employ hot plate or microwave digestion with concentrated acids (1), (3), (5), (6).
Hence, ultrasonic extraction may be used in lieu of the more rigorous strong acid/high temperature digestion methods (for example,
see Ref (1) and Test Method E1613), provided that the performance is demonstrated using accepted criteria as delineated in Guide
E1775.
5.2 In contrast with hot plate or microwave digestion techniques, ultrasonic extraction is field-portable, which allows for on-site
sample analysis.
6. Apparatus and Materials
6.1 Sonicator, 50 W minimum power; proper operation of the sonicator shall be confirmed prior to initial use and periodically
thereafter.
6.2 Plastic Centrifuge Tubes, 50 mL, with screw caps.
6.3 Analytical Balance, accuracy better than or equal to
60.002 g.
6.4 Mortar and Pestle, pug mill, or wigglebug.
6.5 Dry Ice (CO (s)).
6.6 Cooler, for storage of dry ice.
6.7 Plastic or Glass Rods, 0.6 to 1.0 cm diameter,
15 to 20 cm length; tapered at one end to conform to the shape of the bottoms of the 50 mL centrifuge tubes.
6.8 Powderless Plastic Gloves. Powderless Plastic Gloves.
6.9 Tweezers. Tweezers.
6.10 Class A Pipets, 5 or 10 mL or both, and other volumes as needed.
NOTE 1—Precision digital mechanical pipettors using replaceable tips meet Class A requirements.
The boldface numbers given in parentheses refer to a list of references at the end of the text.
E1979 − 12 (2016)
6.11 Laboratory Wipes, wet or dry, or both.
6.12 Power Source for Sonicator. Power Source for Sonicator.
6.13 Sieves, Number 10 (1.9 mm) and 250 μm.
6.14 Collection Tray. Collection Tray.
6.15 Rubber Mallet. Rubber Mallet.
6.16 Nylon Brush. Nylon Brush.
6.17 Aluminum Pie Tins. Aluminum Pie Tins.
6.18 Dust Mask. Dust Mask.
6.19 Glass or Plastic Stirring Rods. Glass or Plastic Stirring Rods.
6.20 Aluminum Foil (conventional thickness for household use, that is, not heavy duty).
6.21 Graphite Pencil Graphite Pencil.
7. Reagents
7.1 ASTM Type I Water, in accordance with Specification D1193.
NOTE 2—Commercially available distilled or deionized water meets ASTM Type I water specifications.
7.2 Extraction Solution, 10 % or 25 % v/v HNO /H O; prepared from reagent grade concentrated nitric acid (70 to 71 % HNO )
3 2 3
and ASTM Type I water.
NOTE 3—Air filter samples require 10 % nitric acid (v/v) for extraction, while all other sample matrices require 25 % v/v HNO /H O.
3 2
8. Procedure
8.1 Testing of Sonicator:
8.1.1 Before use, ensure proper operation of the sonicator by employing the following diagnostic test.
8.1.1.1 Turn on the sonicator and allow for a reasonable warm-up period, as recommended by the instrument manufacturer.
8.1.1.2 Insert the tip of a graphite pencil into the bath.
8.1.1.3 If the sonication device is operating properly, graphite in solution will be observed streaming off the tip of the pencil.
8.1.2 Alternatively, demonstrate proper operation of the sonicator according to the following procedure:
8.1.2.1 Fill the sonicator bath with warm water (ca. 45°C) to a level about half-full, and add a small amount (for example, three
drops) of surfactant
8.1.2.2 Turn on the sonicator for a minimum of 5 min to degas the solution. Turn off the sonicator.
1 3
8.1.2.3 Place aluminum foil (that is cut to a size conforming to ⁄2 to ⁄4 of the area of the bottom of the sonicator bath) on the
bottom of the sonicator bath. Lower the foil at an angle to prevent the trapping of air beneath the foil. Ensure that a narrow layer
of solution remains between the foil and the bottom of the sonicator bath. The foil shall be parallel and centered to the bottom of
the sonicator.
8.1.2.4 Turn on the sonicator for a period of 45 s.
8.1.2.5 Examine the aluminum foil after sonication. The foil should be observed to contain a myriad of small holes and bumps,
and may be torn apart. Also, the perforation observed should be uniform; that is, all portions of the foil should be observed to have
a high density of holes and perhaps tears. If the foil is not affected in this manner, then the sonicator performance is inadequate
for the purposes of this practice.
8.2 Dry Paint Film Samples:
NOTE 4—This practice assumes paint samples collected in accordance with Practice E1729.
8.2.1 Don a pair of gloves.
8.2.1.1 If the desired reported lead concentration units are to be in terms of lead mass per unit area of sample, and the estimated
sample mass is greater than or equal to 0.25 g, then quantitatively transfer the entire sample to an analytical balance and weigh
to the nearest 60.002 g. Under these circumstances, do quantitative transfer and sample weighing prior to grinding and
homogenization as described later in this practice.
8.2.1.2 If the desired reporting units of lead concentration are to be in terms of lead mass per unit mass of sample, or if the
desired reporting units are to be in terms of lead mass per unit area and the estimated mass of the sample is less than 0.25 g, then
quantitatively transfer the sample to a mortar and pestle or a labeled 50 mL centrifuge tube. Use tweezers if necessary for
quantitative sample transfer. Clean tweezers before and after use with laboratory wipes.
8.2.2 Sample Grinding and Homogenization:
E1979 − 12 (2016)
8.2.2.1 Grind and homogenize paint film sample to a fine powder using a mortar and pestle, pug mill, or wigglebug.
Quantitatively transfer the ground and homogenized a paint sample to a weighing vessel or weighing paper (see below).
Thoroughly clean mortar and pestle, wigglebug, or pug mill with moistened laboratory wipes prior to and following grinding, and
then dry.
8.2.2.2 Alternatively, place paint film sample in a clean, dry 50 mL centrifuge tube, and place the tube in dry ice. Using a plastic
or metal rod, grind and homogenize the super-cooled, brittle paint sample to a fine powder. Thoroughly clean rod with laboratory
wipes prior to and following grinding procedure. Avoid condensation of water onto the sample by sealing the sample and allowing
it to warm to ambient temperature before weighing.
NOTE 5—The use of dry ice as described assists greatly in the grinding and homogenization of dry paint film samples.
8.2.3 If the total sample mass is greater than or equal to 0.25 g, 0.25 g, or if the total sample mass is less than 0.25 g and the
desired reported lead concentration is to be in units of mass of lead per unit mass of sample, weigh 0.05 to 0.25 g of ground and
homogenized paint sample to the nearest 60.002 g, and record the sample mass.
NOTE 6—If the desired reporting units are to be in terms of mass of lead per unit area of sample, and the sample mass is estimated to be less than 0.25
g, a larger sample may be collected in order to obtain more mass (thereby enabling the sample to be treated as described in 8.2.1.1).
8.2.4 If the total sample mass is less than 0.25 g and the desired reported lead concentration is to be in terms of mass of lead
per unit area of collected sample, then the sample need not be weighed. However, the entire ground and homogenized sample must
be placed in the tube for extraction as described below.
8.2.5 Place the sample in a clean, dry, labeled 50 mL polypropylene centrifuge tube. To ensure quantitative sample transfer, rinse
materials used for transferring samples with a minimum of dilute (5 %) nitric acid, and direct the rinsate into the centrifuge tube.
8.2.6 Using a class A pipet, introduce 5 mL of 25 % HNO to the centrifuge tube containing the ground and homogenized paint
sample. Shake the centrifuge tube briefly to ensure that no solid paint material remains stuck to the bottom of the tube. Rinse the
inside of the centrifuge tube with a minimum quantity of 5 % HNO in order to ensure immersion of all solid material.
8.2.7 Cap the centrifuge tube, and place in an upright position in the sonicator bath.
8.2.8 Ensure that the bath of the sonicator contains enough water so that the water level is at least 2.5 cm above the level of
liquid within the centrifuge tube.
8.2.9 Repeat steps 8.2.1 – 8.2.8 as needed, depending on the size of the ultrasonic bath and the number of samples.
NOTE 7—Depending on the size of the sonicator, many centrifuge tubes may be immersed in the bath at one time. A custom rack for the centrifuge
tubes may be purchased or constructed to allow for the regular and orderly placement of multiple tubes in the sonicator bath.
8.2.10 Apply ultrasonic energy to the crushed and acidified samples within the immersed centrifuge tubes for at least 30
min.30 min.
8.2.11 Remove centrifuge tubes from the bath. Keep tubes in upright position.
8.2.12 Remove caps from centrifuge tubes that contain samples that were subjected to ultrason
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.