arpadveress 
Protection concepts of types of protection “d”, “p” and “t” acceptable for non.electrical equipment.
The protection concepts for the types of protection “d”, “p” and “t” are based respectively on the types of protection available for electrical equipment:
• “d” defined in IEC 60079-1,
• “p” defined in IEC 60079-2 and,
• “t” defined in IEC 60079-31.
All technical requirements apply.
The nature and ignition sources of non.electrical equipment shall be considered when applying types of protection “d”, “p”, or “t” to non.electrical equipment.
It means Ex knowledge shall be there for non.electrical manufacturers too. Certain measures are not all the time satisfactory.
Keep up good work.
Arpad
