GB/T 46747-2025 Rapid determination of heavy metals in furniture coatings - X-ray fluorescence spectrometry English, Anglais, Englisch, Inglés, えいご
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ICS 13.220.10
CCS H 57
National Standard of the People's Republic of China
GB/T 46747-2025
Rapid determination of heavy metals in furniture coatings - X-ray fluorescence spectrometry
家具涂层中重金属元素的快速测定 X射线荧光光谱法
Issue date: 2025-10-31 Implementation date: 2026-05-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Principle
5 Reagents and Materials
6 Apparatus and Equipment
7 Preparation of Test Specimens
8 Test Procedure
9 Processing of Test Data
10 Test Report
Appendix A (Informative) Determination of Target Element Content in Paint Coating Calibration Samples
Appendix B (Informative) Measurement Conditions for X-ray Fluorescence Spectrometers
Appendix C (Informative) Detection Limits, Quantification Limits, and Verified Content Ranges for X-ray Fluorescence Spectrometry
References
Warning: X-ray fluorescence spectrometers generate ionizing radiation during operation. Operators should receive training in the use of X-ray fluorescence spectrometers, follow the safety instructions provided by the manufacturer and national occupational radiation safety regulations, and perform standardized operations.
1 Scope
This document describes an X-ray fluorescence spectrometric method for the rapid determination of eight heavy metal elements—lead (Pb), cadmium (Cd), chromium (Cr), barium (Ba), mercury (Hg), arsenic (As), selenium (Se), and antimony (Sb)—in furniture coatings.
This document is applicable to the rapid determination of Pb, Cd, Cr, Ba, Hg, As, Se, and Sb in paint coatings on the surfaces of wooden and metal furniture, as well as for screening the migration levels of these eight elements in coatings.
Note: When the elemental content exceeds the migration limit, chemical analysis methods should be used to further verify the migration level.
2 Normative References
The content of the following documents constitutes indispensable provisions of this document through normative reference in the text. For dated references, only the edition corresponding to that date applies. For undated references, the latest edition (including any amendments) applies.
GB/T 16597 Methods for Analysis of Metallurgical Products — General Rules for X-ray Fluorescence Spectrometry
GB/T 37361 Determination of Paint Film Thickness — Ultrasonic Thickness Gauge Method
JB/T 12962.1 Energy Dispersive X-ray Fluorescence Spectrometers — Part 1: General Technical Requirements
3 Terms and Definitions
The following terms and definitions apply to this document.
3.1 Fundamental Parameter Method
A theoretical calculation method for determining elemental content in samples, which uses a mathematical model based on a fundamental parameter database to theoretically compute the spectral distribution of primary incident X-rays, interactions between X-rays and matter (including mass absorption coefficients, fluorescence yields, line fractions, absorption jump ratios, scattering, etc.), and instrument optical path influence factors to obtain a calculated spectrum. An iterative algorithm is then applied to converge the calculated spectrum with the detector-acquired spectrum to the required accuracy.
4 Principle
Primary X-rays generated by an X-ray tube, after filtration or monochromatization, irradiate the sample surface. Inner-shell electrons of the analyte elements are excited, causing energy-level transitions and emitting characteristic X-ray fluorescence. An energy-dispersive detector resolves and measures the intensity of the characteristic X-ray fluorescence from different elements. This intensity, after theoretical calculation via the fundamental parameter method, is proportional to the mass fraction of the element in the sample. A calibration curve is established using standard samples/reference materials or calibration samples prepared by the standard addition method to determine the mass fraction of the target element in the sample.
5 Reagents and Materials
5.1 Mixed standard solution containing Pb, Cd, Cr, Hg, As, Se, and Sb: Use elemental standard stock solutions certified by national authorities and granted reference material certificates, with mass concentrations of 1,000 mg/L or higher, in aqueous matrix, hydrochloric acid (nitric acid) matrix (≤5%), or organic matrix.
5.2 Barium (Ba) standard solution: Use elemental standard stock solution certified by national authorities and granted reference material certificate, with mass concentration of 10,000 mg/L, in nitric acid matrix (≤5%) or organic matrix.
5.3 Blank paint: Common paints for wooden furniture such as water-based wood paint or acrylic wood paint, with content of each of the eight analyte elements less than 0.5 mg/kg.
5.4 Wooden or metal substrate: Preferably using common wooden materials or metal substrates for furniture.
5.5 Glass plate or polytetrafluoroethylene (PTFE) plate: Flat surface, resistant to solvent corrosion.
6 Apparatus and Equipment
6.1 X-ray fluorescence spectrometer: Benchtop or handheld energy-dispersive X-ray fluorescence spectrometer, complying with JB/T 12962.1 or GB/T 16597, with detector resolution <135 eV @ Mn Kα. The software shall include quantitative functionality based on the fundamental parameter method and allow customization of multi-layer sample structures.
6.2 Manual coater: Adjustable blade-type or fixed-gap type, with flat surface, resistant to solvent corrosion, non-reactive with paint to avoid contamination.
6.3 Cutting tool: Electric saw or other tool suitable for cutting wooden and metal materials.
6.4 Ultrasonic thickness gauge: Accuracy not less than 1 μm, maximum measurement not less than 500 μm.
7 Preparation of Test Specimens
When using a benchtop X-ray fluorescence spectrometer, cut the furniture sample with a cutting tool (6.3) to a size matching the instrument sample port. When using a handheld X-ray fluorescence spectrometer, no cutting is required; test directly on a flat surface of the furniture.
8 Test Procedure
8.1 Preparation of Paint Coating Calibration Samples
8.1.1 Dilute the mixed standard solution containing Pb, Cd, Cr, Hg, As, Se, and Sb (5.1) with water-based solvent, organic solvent, or amphiphilic solvent (according to the medium) to concentrations of 10 mg/L, 25 mg/L, 50 mg/L, 100 mg/L, 200 mg/L, and 500 mg/L. Then, mix with blank paint (5.3) at a mass ratio of 1:1 to prepare spiked paints with different concentration levels.
8.1.2 Dilute the barium (Ba) standard solution (5.2) with water-based solvent, organic solvent, or amphiphilic solvent (according to the medium) to concentrations of 25 mg/L, 100 mg/L, 200 mg/L, 500 mg/L, and 1,000 mg/L. Then, mix with blank paint (5.3) at a mass ratio of 1:1 to prepare spiked paints with different concentration levels.
8.1.3 Apply the spiked paints prepared in steps 8.1.1 and 8.1.2 onto wooden or metal substrates (5.4) using a manual coater (6.2). Place them in a dust cover to prevent dust contamination and allow to dry at room temperature to form films. The paint film thickness selected for the manual coater (6.2) should be in the range of 20 μm to 200 μm.
8.2 X-ray Fluorescence Spectrometer Instrument Measurement Conditions
Refer to the instrument operating manual to select appropriate measurement conditions for testing, or directly use the instrument's built-in method for testing. Appendix B provides reference testing conditions for the instrument.
