1.1 这些符号规定了由塑料材料制成的管件尺寸的术语。它包括一个带有定义的字母名称列表，然后是典型配件的图纸，重要尺寸根据这些字母名称进行标记。 1.2 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。

1.1 These symbols specify terminology for the dimensions of pipe fittings made of plastic materials. It consists of a list of letter designations with definitions, followed by drawings of typical fittings, with the significant dimensions labeled in accordance with these letter designations. 1.2 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.