Lead compounds which, when mixed in a ratio of 1:1000 with 0.07M hydrochloric acid and stirred for one hour at a temperature of 23°C ± 2°C, exhibit a solubility of 5% or less (see ISO 3711:1990 "Lead chromate pigments and lead chromate-molybdate pigments-Specifications and methods of test") are considered insoluble and are not subject to these Regulations unless they meet the criteria for inclusion in another hazard class or division.