第三版取消并取代第二版（ISO 312-1980），第二版为次要修订版。规定了原理、试剂、仪器、样品、程序和结果表达。图中给出了仪器的示例。

This third edition cancels and replaces the second edition (ISO 312-1980), of which it constitutes a minor revision. Specifies principle, reagents, apparatus, sample, procedure and expression of results. A figure gives an example of apparatus.