This document specifies a spectrophotometric method for the determination of nitrogen in steel . The method is applicable to determination of nitrogen mass fraction between 0,000 6 % and 0,050 % in low alloy steels and between 0,01 % and 0,050 % in high alloy steels. However, the method is not applicable to samples containing silicon nitride. The method doesn't apply to samples having silicon contents > 0,6 %