arpadveress 
it says: “This standard provides the specific requirements for the design, selection, erection and the required initial inspection of electrical equipment in hazardous areas. This standard is also based on manufacturer’s instructions being followed. On-going inspection, maintenance and repair aspects also play an important role in control of hazardous area installations and the user’s attention is drawn to IEC 60079-17, IEC 60079-19 and manufacturer’s instructions for further information concerning these aspects.”
a very interesting part of it from above: “This standard is also based on manufacturer’s instructions being followed.“
So keep up good work and read Ex compliance docs plus manuals.
Arpad
