GB24409-2009 Automobile Coatings Testing
Project Introduction
GB24409-2009 is the national standard for the limit of harmful substances in automobile coatings. GB24409-2009 "Limit of Harmful Substances in Automobile Coatings" was issued on September 30, 2009 and implemented on June 1, 2010. Its purpose is to reduce the harm of automobile coatings to human health and pollution to the environment. It is the need of today's environmental protection and a concrete manifestation of the development towards an environmentally friendly society. The implementation of this mandatory standard effectively reduces the emission of volatile organic compounds (VOC) during automobile painting, strictly controls the use of highly toxic chemicals such as benzene, glycol ethers, heavy metals, etc., and plays an important role in protecting the environment and human health.

The standard specifies the requirements, test methods, inspection rules, packaging marks, coating safety and protection for the allowable limit of harmful substances to the human body and the environment in original coatings, repair coatings and component coatings for passenger cars, commercial vehicles, trailers, and automobile trains. It is applicable to all types of automobile coatings except putty and special functions. Special functional coatings include PP water, anti-stone impact coatings, and bridging water. Dacromet coatings are not suitable for this standard. The entire content of the standard is mandatory.
The standard divides automotive coatings into two categories: Class A solvent-based coatings, which are further divided into thermoplastic, one-component cross-linking, and two-component cross-linking; Class B is water-based coatings (including electrophoretic coatings), powders, and light-curing coatings.

Test method
6.2.1 The test of volatile organic compound content (VOC) shall be carried out in accordance with the provisions of Appendix A of this standard.
6.2.2 The test of restricted solvents in solvent-based coatings shall be carried out in accordance with the provisions of Appendix B of this standard.
6.2.3 The test of restricted solvents in water-based coatings shall be carried out in accordance with the provisions of Appendix C of this standard.
6.2.4 The test of heavy metals (Pb, Cd and Hg) shall be carried out in accordance with the provisions of Appendix D of this standard.
6.2.5 The test of heavy metals (C+) shall be carried out in accordance with the provisions of Appendix E of this standard.