Specifies reference conditions, acceptance test methods and the most important characteristic data of different dryers. Applicable to dryers working in the effective (gauge) pressure range of 0,16 to 40 MPa, but excluding: liquid absorption types; cooling with aftercooler; overcompression. A test report form is shown in annex A. Annex b includes a typical testing system for air dryers. Saturation pressure and density of pure water vapour is tabulated in annex C.