Member States shall take all appropriate measures to ensure that products may be made available on the market and put into service only if, when properly installed and maintained and used in accordance with their intended use, they comply with this Directive.

This Directive shall not affect Member States’ entitlement to lay down such requirements as they may deem necessary to ensure that persons and, in particular, workers are protected when using relevant products provided that this does not mean that such products are modified in a way not specified in this Directive.

At trade fairs, exhibitions and demonstrations, Member States shall not prevent the showing of products which do not comply with this Directive, provided that a visible sign clearly indicates that such products do not comply with this Directive and that they are not for sale until they have been brought into conformity by the manufacturer. During demonstrations, adequate safety measures shall be taken to ensure the protection of persons.