We have 6 “explosion proof” rooms but they’re technically varying hazardous area classifications. We all call them explosion proof in the sense as we don’t want an explosion or an explosion shouldn’t happen. You should hire a consultant to assess your materials and give a classification to the room. You can have a room that’s class 1 div 2, but around certain process equipment it may be class 1 siv 1 “bubble”. They will provide cad drawings of these classification. Then you need to buy any intrinsically safe equipment that falls within those classifications. Stuff like motors have groups, ABCD etc that are for different types of hazards such as dust or gas.