arpadveress 
In possible hazardous environment:
– with an Ex barrier all non Ex installations can be operated…
– Ex d and Ex e means explosion-proof…
– tertiary explosion protection is more than enough…
– if we are below ignition temperature, that is a perfect level of protection…
– it is enough if we buy an Ex certified product, no more Ex type of handling required…
– in EU besides ATEX type certification IECEX is acceptable as well…
There are many myths, which may lead to catastrophic situations if approved that way.
Keep up good work!
Arpad
