This is downright scary... isn't there any regulation in the US demanding a hazardous area risk assessment that outlines where you have C1D1 or D2 before you install gear in it?
There are assessments done, in many of these plants they have Assessments and even Area Classification Maps. The point I was trying to make was that in many of the plants I have worked in Class 1 Div 1 is a very small area. Many times Plant Engineers will assume Class 1 Div. 1 just to be safe. When I send them a quote for some equipment and the Div.1 equipment is about double the Div. 2 price they are then forced to go look at the Classification Maps and Assessments to determine if the area is indeed Div.1. Most of the time they find it is not and will then opt for the lower cost item.
So it isn't a "Change the Area Classification to fit the equipment in it" kind of situation. That would be SCARY!! It is more like a "are you sure it is Div 1 area? If not don't pay Div 1 prices" situation.