ASTM D3624-85a(2022)

• Abstract:

  SIGNIFICANCE AND USE; 4.1 The permissible level of heavy metals in certain coatings is specified by governmental regulatory agencies. This test method provides a fully documented procedure for determining low concentrations of mercury present in both water and solvent-reducible coatings to determine compliance.; SCOPE; 1.1 This test method covers the determination of the content of mercury in the range between 10 and 1000 ppm (mg/kg) present in liquid coatings, coatings vehicles, or in dried films obtained from previously coated substrates. There is no reason to believe that higher levels could not be determined by this test method, provided that appropriate dilutions and adjustments in specimen size and reagent quantities are made. ; 1.2 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. Specific hazard statements are given in Section 7 and 9.1.1. ; 1.3 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.

• Status: Published
• Publication Date: 31-May-2022
• ICS: 87.040 - Paints and varnishes
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.21 - Chemical Analysis of Paints and Paint Materials

• Refers: ASTM D1193-06 - Standard Specification for Reagent Water
• Effective Date: 01-Mar-2006
• Refers: ASTM D1193-99e1 - Standard Specification for Reagent Water
• Effective Date: 10-Feb-1999
• Refers: ASTM D1193-99 - Standard Specification for Reagent Water
• Effective Date: 10-Feb-1999

Overview

ASTM D3624-85a(2022) is the internationally recognized standard test method for determining low concentrations of mercury in paint using atomic absorption spectroscopy (AAS). Developed and maintained by ASTM International, this method serves as a vital tool in monitoring mercury levels in liquid coatings, coating vehicles, and dried paint films. The method is applicable for mercury content ranging from 10 to 1000 ppm (mg/kg), providing a reliable procedure for regulatory compliance, environmental monitoring, and quality assurance in the paint and coatings industry.

Governmental agencies often regulate permissible levels of heavy metals, such as mercury, in coatings due to their potential toxicity and environmental hazards. As a result, ASTM D3624 serves as a key reference for manufacturers, laboratories, and regulatory bodies seeking to ensure compliance with strict mercury limits in both water-based and solvent-reducible paints.

Key Topics

• Test Scope and Range

  • Measurement of mercury concentrations from 10 to 1000 ppm in paints and coatings.
  • Applicable to both water-reducible and solvent-reducible coatings, as well as dried paint films.
  • Higher concentrations may also be determined with suitable sample preparation and dilution.

• Atomic Absorption Spectroscopy Procedure

  • Utilizes cold-vapor atomic absorption technique for maximum sensitivity.
  • Sample digestion is performed in PTFE-lined vessels to prevent mercury loss.
  • Calibration using mercury standards ensures reliable quantification.

• Safety and Environmental Considerations

  • Detailed guidelines for handling toxic chemicals and mercury compounds.
  • Emphasis on personal safety, proper waste disposal, and environmental protection according to regulatory requirements.

• Quality and Compliance

  • Provides documented procedures for repeatability and reproducibility.
  • Supports compliance with governmental and international regulations regarding heavy metal content in paints.

Applications

The ASTM D3624 method is widely used across various sectors, offering practical value for:

• Paint Manufacturers: Assuring product safety and regulatory compliance by routinely monitoring trace mercury levels in raw materials and finished goods.
• Analytical Laboratories: Performing precise quantification of mercury content in coatings for quality control and certification purposes.
• Regulatory Agencies: Enforcing environmental and health standards by referencing a proven, standardized test method.
• Environmental Health and Safety (EHS): Assessing potential toxic exposure risks and ensuring proper waste management in paint production and application processes.

By providing accurate and reliable mercury determination, this standard helps prevent hazardous mercury contamination in the environment, facilitates trade compliance, and strengthens consumer and occupational safety.

Related Standards

ASTM D3624 references and complements several related standards, including:

• ASTM D1193 - Specification for Reagent Water, essential for quality assurance in sample preparation and dilution.
• Paint and Coatings Analytical Methods - Additional ASTM methods focusing on other heavy metals or chemical constituents.
• International Regulations - Aligned with the World Trade Organization (WTO) Technical Barriers to Trade (TBT) principles for standardized test methods.

For comprehensive heavy metal testing in paints, consider referencing other ASTM analytical methods and local regulatory guidelines to ensure complete compliance.

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Keywords: ASTM D3624, mercury in paint, atomic absorption spectroscopy, low concentrations, heavy metal compliance, paint testing, coatings safety, mercury analysis, regulatory standards, environmental monitoring, laboratory test methods.

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: D3624 − 85a (Reapproved 2022)
Standard Test Method for
Low Concentrations of Mercury in Paint by Atomic
Absorption Spectroscopy
This standard is issued under the fixed designation D3624; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope digested sample is diluted to a known volume with water and
the concentration of mercury is determined using a cold-vapor,
1.1 This test method covers the determination of the content
atomic absorption technique.
of mercury in the range between 10 and 1000 ppm (mg/kg)
present in liquid coatings, coatings vehicles, or in dried films
4. Significance and Use
obtained from previously coated substrates. There is no reason
to believe that higher levels could not be determined by this
4.1 The permissible level of heavy metals in certain coat-
test method, provided that appropriate dilutions and adjust-
ingsisspecifiedbygovernmentalregulatoryagencies.Thistest
ments in specimen size and reagent quantities are made.
methodprovidesafullydocumentedprocedurefordetermining
low concentrations of mercury present in both water and
1.2 This standard does not purport to address all of the
solvent-reducible coatings to determine compliance.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
5. Apparatus
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
5.1 Atomic Absorption Spectrophotometer—Any commer-
Specific hazard statements are given in Section 7 and 9.1.1.
cial instrument having an open sample presentation area in
1.3 This international standard was developed in accor-
which to mount the absorption cell or an instrument designed
dance with internationally recognized principles on standard-
specifically for the measurement of mercury using the cold
ization established in the Decision on Principles for the
vapor technique.
Development of International Standards, Guides and Recom-
5.2 Recorder,0to10mV.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
5.3 Mercury Source Lamp.
5.4 Absorption Cell—Standard spectrophotometer cells 100
2. Referenced Documents
mm long, having quartz end windows may be used. Prior to
2.1 ASTM Standards:
use, the cell must be positioned in the optical path of the
D1193 Specification for Reagent Water
spectrophotometer and held in place by suitable clamps or
straps. The cell should be carefully aligned both vertically and
3. Summary of Test Method
horizontally to give the maximum transmittance.
3.1 The sample of liquid coating or dried film is weighed
5.5 Reduction Vessel—Cylindrical gas washing bottle, 250-
into a polytetrafluoroethylene (PTFE)-lined acid decomposi-
mL, equipped with a coarse (40 to 60-µm) fritted glass inlet
tion vessel and digested at an elevated temperature using
tube and a standard-taper glass stopper. Polyethylene or poly-
sulfuric and nitric acids. Use of a sealed acid decomposition
(vinyl chloride) tubing may be used for connecting the reduc-
vessel prevents loss of mercury during the digestion. The
tion vessel to the absorption cell.
5.6 Flowmeter, capable of measuring a gas flow of 1 L/min.
This test method is under the jurisdiction of ASTM Committee D01 on Paint
and Related Coatings, Materials, andApplications and is the direct responsibility of 5.7 Drying Tube—Approximately 150 by 20-mm (6 by
Subcommittee D01.21 on Chemical Analysis of Paints and Paint Materials.
⁄4-in.) glass tube filled with magnesium perchlorate. The tube
Current edition approved June 1, 2022. Published June 2022. Originally
should be filled each day that it is in use, and the Mg(ClO )
4 2
approved in 1977. Last previous edition approved in 2015 as D3624 – 85a (2015).
should be replaced whenever it becomes saturated (carefully
DOI: 10.1520/D3624-85AR22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
observe after each analysis).
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on NOTE 1—Use of an indicator desiccant at the exit end of the tube will
the ASTM website. make this observation easier.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D3624 − 85a (2022)
5.8 Water Vapor Trap—A second 250-mL gas washing 6.3 Hydroxylamine Hydrochloride Solution (100 g/L)—
bottle (the same as used for the reduction vessel). If preferred, Dissolve 10 g of NH OH·HCl in 100 mL of water. Transfer a
a 250-mL Erlenmeyer vacuum flask fitted with a one-hole
portion of this solution to a small dropping bottle.
stopper and 200 mm of 5-mm outside diameter glass tubing,
6.4 Mercury Solution, Stock (1 mg/mL)—Dissolve 0.1354 g
may be substituted. (Fig. 1)
of HgCl in 50 mL of water. Carefully add 5 mL of concen-
5.9 Mercury Trap—A 250-mL Erlenmeyer vacuum flask
trated H SO and 3 mL of concentrated HNO and dilute to
2 4 3
containing 75 mL of 10 % sulfuric acid and 75 mL of 0.1 N
100 mL. This solution contains 1000 µg/mL of mercury.
potassium permanganate solution to absorb the mercury vapor
after analysis. 6.5 Mercury Standard, Working(0.1µg/mL)—Makesucces-
sivedilutionsofthestockmercurysolutiontoobtainaworking
5.10 Circulating Oven, maintained at 140 6 5 °C.
standard containing 0.1 mg/L (0.1 µg/mL), maintaining a
5.11 Acid Decomposition Vessel, with 25-mL PTFE diges-
concentration of 5 % H SO and 3 % HNO by volume, in the
3 2 4 3
tion cup.
diluted solutions. The working mercury standard and the
5.12 Volumetric Flasks, 100, 250, and 1000-mL.
dilutions of the stock mercury solution should be prepared
fresh each day that it is used.
5.13 Paint Shaker.
5.14 Paint Draw-Down Bar.
6.6 Nitric Acid (sp gr 1.42)—Concentrated nitric acid
(HNO ).
6. Reagents
6.7 Nitrogen.
6.1 Purity of Reagents—Reagent grade chemicals shall be
used in all tests. Unless otherwise indicated, it is intended that 6.8 Potassium Permanganate Solution (0.1 N)—Dissolve
all reagents shall conform to the specifications of the Commit-
15.8 g of KMnO in water and dilute to 1 L.
tee onAnalytical Reagents of theAmerican Chemical Society,
4 6.9 Stannous Chloride Solution(100 g/L)—Dissolve 25 g of
where such specifications are available. Other grades may be
tin (II) chloride (SnCl ) by adding it to 60 mL of concentrated
used, provided it is first ascertained that the reagent is of
HCl (sp gr 1.19) and warming on a hotplate. When all of the
sufficiently high purity to permit its use without lessening the
SnCl has dissolved, transfer to a 250-mLvolumetric flask and
accuracy of the determination.
dilute to volume with water. Mix well. This solution should be
6.2 Purity of Water—Unless otherwise indicated, references
prepared fresh each week that it is used.
to water shall be understood to mean reagent water conforming
to Type II of Specification D1193. 6.10 Sulfuric Acid (sp gr 1.84)—Concentrated sulfuric acid
(H SO ).
2 4
6.11 Sulfuric Acid (1+9)—Carefully mix 1 volume of
The sole source of supply of an acid decomposition vessel, Catalog No. 4745, H SO (sp gr 1.84) into 9 volumes of water.
2 4
known to the committee at this time is the Parr Instrument Co., 211 Fifty-third St.,
Moline, IL 61265. If you are aware of alternative suppliers, please provide this
7. Hazards
information to ASTM International Headquarters. Your comments will receive
careful consideration at a meeting of the responsible technical committee, which
7.1 Concentrated nitric and sulfuric acids are corrosive and
you may attend.
may cause severe burns of the skin or eyes. The vapor from
ACS Reagent Chemicals, Specifications and Procedures for Reagents and
Standard-Grade Reference Materials, American Chemical Society, Washington,
concentratednitricacidisirritatingtomucousmembranes.Use
DC. For suggestions on the testing of reagents not listed by theAmerican Chemical
care in handling these acidic substances. Refer to suppliers’
Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset,
Material Safety Data Sheet.
U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharma-
copeial Convention, Inc. (USPC), Rockville, MD.
FIG. 1 Apparatus
D3624 − 85a (2022)
solution into a sewer system.
7.2 Mercury and its compounds are harmful and accumulate
in the aquatic environment. Mixtures containing mercury
8.7 Construct a standard curve by plotting peak heights
compoundsshouldnotbeflusheddownadrain,butdisposedof
versusmicrogramsofmercury.Peakheightsusedshouldbethe
as hazardous waste.
mean of duplicate determinations on each solution.
7.3 Use only a rubber bulb aspirator for pipetting liquids.
9. Procedure
8. Calibration and Stand
...