Member States shall take all necessary steps to ensure that the vessels may be placed on the market and put into service only if they do not compromise the safety of persons, domestic animals or property when properly installed and maintained and used for the purposes for which they are intended.

The provisions of this Directive shall not affect the right of Member States to specify — with due observance of the Treaty — the requirements they deem necessary in order to ensure that workers are protected when using vessels, provided it does not mean that those vessels are modified in a way unspecified in this Directive.