Ensuring conformity during the design and the manufacturing process is generally the responsibility of the manufacturer. In this process, the manufacturer has to carry out all required controls and checks, to establish the necessary technical documentation and give access to the economic operator placing products on the Union market (or putting them into service). These obligations apply in an equal manner to EU and non-EU manufacturers, regardless of where the manufactured product is imported from.
Disclaimer: Please note that the European Commission cannot provide a legally binding interpretation of the EU legislation, as this is the sole competence of the European Court of Justice. Any remarks from the European Commission services are without prejudice to the position the Commission might take should related cases arise in a procedure before the Court of Justice.