DIPERMET unit determines the t₀--value of steel plates to be enameled. The t₀--value is the time required for the diffusion of hydrogen, generated on one side of a steel plate, to the other side of the plate. The t₀--value is in direct relation to the effective diffusion coefficient (D_eff) of the atomic hydrogen solved in the steel sheet. This test using DIPERMET serves the corresponding European Norm EN 10209 as clearance assay for enameling steel. It supports conclusions regarding the sensitivity of enameled steel to scaling.