ISO 12944-2:2017涉及钢结构所暴露的主要环境的分类以及这些环境的腐蚀性。 ISO 12944-2:2017 - 根据标准样品的质量损失（或厚度损失）定义了大气腐蚀性类别，并描述了钢结构所暴露的典型自然大气环境，并对腐蚀性的评估提供了建议， - 描述浸入水中或埋在土壤中的不同类型的环境 - 提供了一些特殊的腐蚀应力的信息，这些腐蚀应力会导致腐蚀速率的显着增加或对防护涂料体系的性能提出更高的要求。 与特定环境或腐蚀性类别相关的腐蚀应力是控制防护涂料体系选择的一个重要参数。

ISO 12944-2:2017 deals with the classification of the principal environments to which steel structures are exposed, and the corrosivity of these environments. ISO 12944-2:2017 - defines atmospheric-corrosivity categories, based on mass loss (or thickness loss) by standard specimens, and describes typical natural atmospheric environments to which steel structures are exposed, giving advice on the estimation of the corrosivity, - describes different categories of environment for structures immersed in water or buried in soil, and - gives information on some special corrosion stresses that can cause a significant increase in corrosion rate or place higher demands on the performance of the protective paint system. The corrosion stresses associated with a particular environment or corrosivity category represent one essential parameter governing the selection of protective paint systems.