Difference Between Purge Panel & Flameproof Panel

If you get Wikipedia up, and enter "electrical equipment in potentially explosive atmospheres", then all your questions will be answered, Mildred. Just don't play around without getting properly trained.

A bit touchy this morning aren't we?

The very basic difference and simplified explanation is one is a specially constructed monstrously thick walled aluminum enclosure with many bolts through to hold the door shut, very expensive, and is incorrectly called explosion proof in the USA - in reality, the explosion does occur but is dissipated by travel through long threaded connections.

The other has a gas under pressure applied to "purge" out flammable gasses and keep them out via the pressure applied inside the panel that is greater than atmospheric. This can be a basic thin walled NEMA 4 enclosure with a purging unit applied to it.

I am more familiar with Class I Div.1 and 2 and have used both in both classifications. From personal experience, customers tend to go with the Flameproof in Div.1, closest to your Zone 1, probably because the protection is mechanical and inherent so it is always there in this style, while a purge unit can fail. Now it is supposed to shut the panel down in the case of a failure, but why take the chance?

For a start try reviewing "Standard for Ovens and Furnaces, NFPA 86"

I am not sure you have asked the right question to start with, and also not sure that you understand what Zone1 &2 are.

I am knowledgeable in this field, and can answer all of your qustions, but will not provide you information that could endanger you or others if not fully understood.

Get back to school, or hire a competent person.