本文件规定了使用凯氏定氮法变体测定天然生胶和天然胶乳中氮的宏观方法和半微观方法。 注:天然橡胶中氮的测定通常是为了估算蛋白质含量。也存在少量非蛋白质含氮成分。然而，在天然胶乳制备的干固体中，这些材料对总氮含量的贡献很大。

This document specifies a macro-method and a semi-micro method for the determination of nitrogen in raw natural rubber and in natural rubber latex using variants of the Kjeldahl process. NOTE The determination of nitrogen in natural rubber is usually carried out in order to arrive at an estimate of the protein content. Minor amounts of non-proteinous nitrogen containing constituents are also present. However, in the dry solids prepared from natural rubber latex, these materials can make a substantial contribution to the total nitrogen content.