1. Member States shall not, on grounds relating to the aspects covered by this Regulation, prohibit, restrict or impede the making available on the market and the putting into service of appliances which comply with this Regulation.
2. Member States shall not, on grounds relating to the risks covered by this Regulation, prohibit, restrict or impede the making available on the market of fittings which comply with this Regulation.
3. At trade fairs, exhibitions, demonstrations or similar events, Member States shall not prevent the showing of appliances or fittings which do not comply with this Regulation, provided that a visible sign clearly indicates that such appliances or fittings do not comply with this Regulation and that they are not for sale until they have been brought into conformity. During demonstrations, adequate safety measures shall be taken to ensure the protection of persons, domestic animals and property.