is it required? is there any checklist for it? what is the standard with definition?
not really any. sure, Ex design is a must have, if it is installed within the possible Ex hazardous environment.
on the other side all hazardous area owners are obliged to cover all possible ignition sources. with regards to electrical Ex installations, the Ex inspection is a good tool to meet all compliance issues. do we follow here the electrical path?
sure, we do. in all manuals of Ex non.electrical you will find the request of periodical inspection – and if not, your best practice shall be to follow how you do on electrical.
keep up good work!