Standard regulations for equipment used in side hazardous areas with potentially explosive atmospheres is a core issue for theEuropean Union. Thus, they took the lead in developing standards which became famous as ATEX directives (ATmosphèresEXplosibles). They apply to all kinds of, electrical or non-electrical equipment and safety devices as well as machines and industrial facilities located within potentially explosive atmospheres.Since July 2003 it is mandatory to use devices which have a ATEX type approval all across Europe.