The publication of ISO 10138 gives rise to the cancellation of ISO 4936:1984. The method described determines chromium in non-alloy and low-alloy steels and iron. It is applicable to chromium contents between 0,002 % (m/m) and 2,0 % (m/m). Specifies normative references, principle, reagents, apparatus, sampling, procedure, expression of results and test report. Procedures for the determination of instrumental criteria are given in annex A. Additional information on the international co-operative tests are given in annex B, annex C represents the precision data graphically.