Why do we follow the Ex standards?

is it a common language for professionals? or as per few days before one told me: “My answer is related with the judgment procedure after an accident. If after the accident there is an objective and scientific search is done, the people will consider the standards and obey the rules which are stated in those.”, because we do want to have a common understanding with the one expert who is there to assess my responsibility for the case? does it matter?
Yes!

Ps: subject of discussion was about the point: installation of Ex d cable gland with compounds or not.
Keep up good work!