It refers to the harmonization of the laws of the Member States relating to equipment and protective systems intended for use in potentially explosive atmospheres.Regarding ATEX 99/92/EC Directive, the requirement is that Employers must classify areas where potentially explosive atmospheres may occur, into zones.The aim of Directive 2014/34/EU is to allow the free trade of ‘ATEX’ equipment and protective systems within the EU by removing the need for separate testing and documentation for each member state.Manufacturers/suppliers (or importers, if the manufacturers are outside the EU) must ensure that their products meet essential health and safety requirements and undergo appropriate conformity procedures.This usually involves testing and certification by a ‘third-party’ certification body (known as a Notified Body e.g. UL, Vinçotte, Intertek, Sira, Baseefa, Lloyd's, TUV ICQC) but manufacturers/suppliers can ‘self-certify’ Category 3 equipment (technical dossier including drawings, hazard analysis and users manual in the local language) and Category 2 non-electrical equipment.