Hydrogen

The surface ignition temperature of hydrogen is T1 that is 450 celcius . Each gas data must be cheked througly before specifying equipment .
  Electrical equipnment sutable for use in hazardous areas has to be marked with the protection it affords . The mark commences with the letters EX , which have been internationally aggred to indicate explosion protection , continues with the type , and where relevant , the group for which the equipment has been certified , and concludes with the temperature classification . An example of marking CE 0000 II 2 G ; CE suitable for use in the European Community , 0000 the certifying test house registration number , II explosion proof , 2 category , and G suitable for gas .

  Nearly all the accessories described in this chapter , including switches , socket outlets and boxes , are available in versions with various classes of hazaed protection . Distribution equipment and luminaires , which are discussed in a variety of types of protection .