Defines a procedure for obtaining and for assessing the data necessary to establish long-time stress rupture values for steels for pressure purposes for steels where properties different from those internationally agreed are being claimed. The purpose of a standard procedure is to minimize any differences in long-time estimates obtained in different countries due to differences in the quantity and duration of the data used and differences in the method of analysing the data. This title may contain less than 24 pages of technical content.