About 30% of my career has been in design/construction of IEC/CENELEC facilities; the last one was finished a bit over 11 years ago. The EU ATEX directives had just come into force. The major affect with regard to the project was the new marking standards. Little else made any significant difference to our design.
The US domestic Zone system in not the same as either the IEC or the CENELEC implementation. Canada?s system is very close though. Back in the 1993 Cycle, one of my comments was used as the basis for rejecting the US system at the time - primarily because many designers and inspectors had a hard enough time with the Division system. (No big deal - they could have picked any one of a couple of dozen)
A major US use has been on the Alaska Pipeline. Most of the Pipeline construction is modular. Modules of all types are fabricated in less hostile environments and shipped to Alaska. Many go all the way to the North Slope on barges. The basic advantage is that ?standard? Zone construction is lighter. Because the Modules are enclosed, many are Classified Zone 1. Classic Zone 1-type equipment is often less expensive than Division 1 equipment.
I have heard a few other US facilities have also tried the US Zone system ? I don?t the details.
Availability is a mixed bag. Most US manufacturers simply had their conventional Division equipment dual rated. In that since it isn?t too difficult to get Zone equipment, but virtually all economic benefits disappear too. I only know of one domestic manufacturer of true Zone equipment.
