This European Standard describes a method for the spectrophotometric determination of nitrogen in steels. This method is mainly applied for the determination of nitrogen in non-alloy steels with very low nitrogen contents. However, it can be used for all ferrous alloys with low contents of hydrochloric soluble nitrogen, as long as it is not in the form of acid-resistant silicon nitride. This very resistant nitride has only been found, until now, in samples of steel with silicon manufactured without aluminum additions and, therefore, only in the sheets. The method is applicable to steels whose nitrogen content is between 0.0005% and 0.005% (m/m). NOTE- The method has been successfully tested in pure iron with a nitrogen content of 0.0038% (m/m), (see annex).