Provide professional and efficient authority gouache LHAMA, watercolor ASTMD4236 certification, testing and certification for the definition of Yantai LHAMA art materials, 13 February 1995, CPSC issued a legal document of the art materials are defined: - The following products are not in violation of some LHAMA regulations. (1) can be used for general purposes and not necessarily only for the art pencils, pens, Marks pens, chalk, etc; (2) the supporting tools and equipment used in artistic creation; (3) the surface of the material, such as dyed color book and canvas.