Non electrical Ex installations shall be Ex certified both under ATEX and IECEX.

Only difference in case of ATEX Directive manufacturer's self declaration is a possible way both for category 2 and 3.

What is the case if there are combined electrical installations like sensors, switches? Still the manufacturer's self declaration is a way to go? Let us see:

1. All combined electrical installations are Ex certified, in that case YES - but the installation of those Ex certified devices shall happen via Ex competent personnel
2. All combined electrical installations are non Ex, in that case the whole machine shall be considered as per electrical device and shall be Ex type approved in partnership with an ExNB