Whereas , in each Member State , mandatory provisions define in particular the safety level required of simple pressure vessels by specifying design and operating characteristics , conditions of installation and use and inspection procedures before and after placing on the market; whereas these mandatory provisions do not necessarily lead to different safety levels from one Member State to another but do , by their disparity , hinder trade within the Community.. This sentence is hard to understand. A simpler version with equivalent meaning is the following:
In the Member States , there are mandatory regulations that regulate the design and functional features , the installation and use conditions and the procedures for monitoring before and after placing on the market , in particular the level of safety that simple pressure vessels must have . Although these mandatory provisions do not necessarily lead to a different level of security from Member State to Member State , they nevertheless hinder intra-Community trade because of their different design .