In order to guarantee the free movement of products within the Union, it is necessary to ensure that products are compliant with Union harmonisation legislation and therefore fulfil requirements providing a high level of protection of public interests, such as health and safety in general, health and safety in the workplace, protection of consumers, protection of the environment, public security and protection of any other public interests protected by that legislation. Robust enforcement of these requirements is essential to the proper protection of these interests and to create the conditions in which fair competition in the Union market for goods can thrive. Rules are therefore necessary to ensure this enforcement, regardless of whether products are placed on the market via offline or online means and regardless of whether they are manufactured in the Union or not.