本指令应适用于最大允许压力PS大于0.5巴的压力设备。压力不超过0.5巴的压力设备不会因压力而造成重大风险。因此，它在欧盟内部的自由行动不应该有任何障碍。本指令还应适用于由多个压力设备组成的组件，这些压力设备组装成一个完整的功能整体。这些组件可以是简单的组件，如压力锅，也可以是复杂的组件，如水管锅炉。 如果组件制造商打算将其投放市场，并将其作为组件投入使用，而不是以其组成的非组装元件的形式投入使用，则该组件应符合本指令。然而，本指令不适用于现场压力设备的组装，也不适用于非制造商用户的责任，如工业装置。

This Directive should apply to pressure equipment subject to a maximum allowable pressure PS greater than 0,5 bar. Pressure equipment subject to a pressure of not more than 0,5 bar does not pose a significant risk due to pressure. Therefore, there should not be any obstacle to its free movement within the Union.This Directive should also apply to assemblies composed of several pieces of pressure equipment assembled to constitute an integrated and functional whole. Those assemblies may range from simple assemblies such as pressure cookers to complex assemblies such as water tube boilers. If the manufacturer of an assembly intends to place it on the market and put it into service as an assembly - and not in the form of its constituent non- assembled elements - that assembly should comply with this Directive. However, this Directive should not apply to the assembly of pressure equipment on the site and under the responsibility of a user who is not the manufacturer, as in the case of industrial installations.