This method accelerates the natural weathering rate of a sample causing diagnostic weathering products. The weekly parameters measured are pH, Eh, conductivity, sulphate-ion concentration, acidity and alkalinity. Selected metals are measured on a less regular basis (weeks 0, 1, 2, 4, 8, 12, 16 and 20). Weekly cycles are used with three days of dry air, followed by three days of water saturated air. Day 7 uses a leach with water. It is recommended that a test duration of 20 weeks is to be used.