Sorry to start another thread on the same subject I did a few nights ago, but I thought under a different heading I may get more responses... I am trying to figure out the wiring that is required around a spray booth. I am looking at the code requirements and am trying to distinguish the class and division that I am working in.
There will be at least 1 spray booth with an exhaust fan to the outside. Am I correct in my interpretation of the code that inside the spray booth is a Class I Division I classification, and around the spray booth up to 20 ft. and over the spray booth up to 10 ft., is a Class I Division II location??? Thus the wiring method cannot be EMT, but must fall under one of the requirements in 501-4b, rigid metal conduit, threaded steel intermediate metal conduit, etc.....
But if I go outside the 20 ft. distance, I do not have to use any special enclosures for 2 stop start stations I intend on installing for the exhaust fans outside???
Also any pipe going through the Class I Division II location to an area that is unclassified ( or beyond the 20 ft. horizontal or 10ft. vertical, must have a seal off within 10 ft. of the boundary on either side and that pipe must be rigid or threaded steel conduit where it leaves the Class I Division II location....??? If the seal off is 10 ft. on the outside boundary, it can be changed over to EMT?????

Does any of this make sense [Linked Image]
I think I need a course just on hazardous locations [Linked Image] Boy it's hard to decipher some of the wording in the code sometimes....

Looks like if I've interpreted it right, I have a lot of changing of the existing wiring to conform to code....... Well if anyone wants to respond to see if I've got it straight, I would appreciate it, but if it confuses you like it's trying to confuse me... I understand.... Thanks again.... Steve