Determination of factors and measuring their impact on the amount of nitrogen in the metal is key attribute when optimizing technological and operational measures tending to minimize, respectively prevent of the final steel nitridization. Knowing the rate of influence of individual factors on the nitrogen content in the metal is crucial in dealing with prediction of the quantity for the production and processing stages of steel production in a closed production cycle. In this paper, factors determining nitrogen content in crude steel before tapping, using Cohen´s distribution table and graphical expression are presented. Influence of after-blows on nitrogen content is well known, but there are other factors which affect steel nitridization before tapping from oxygen converter.