EU Legislation and ATEX http://ec.europa.eu/growth/sectors/mechanical-engineering/atex/
Directive ATEX 94/9/CE http://eur-lex.europa.eu/legal-content/NL/TXT/HTML/?uri=CELEX:32014L0034&from=EN
The new ATEX Directive 2014/34/EU on equipment and protective systems intended for use in potentially explosive atmospheres is aligned with the 'New Legislative Framework' and will be applicable from 20 April 2016. Guideline to ATEX 94/9/EC http://ec.europa.eu/DocsRoom/documents/9571/attachments/1/translations/en/renditions/native
List of harmonized standards http://ec.europa.eu/growth/single-market/european-standards/harmonised-standards/equipment-explosive-atmosphere/index_en.htm