I have found that you have to really educate yourself regarding hazardous locations. A lot of inspectors are not completely informed of the requirements and therefore make guesses. If you are installing a light fixture it can not be made intrinsically safe. It must be a fixture rated and listed for the hazardous location with the proper raceway and seals. Usually only control items can be made intrinsically safe, such as float switches etc, using the proper components.
I had an inspector walk in on a job I did and condemned the job as soon as he saw thinwall. Kept repeating "All wiring in a hazardous location must be in rigid". He could not understand "intrinsically safe". Took a lot of my time meeting with him and his boss to get it approved. Because I took the time to read and read until I understood hazardous location wiring I was able to stand there, proud of the job, knowing I would not have to change anything. I'm sure if you ask the inspector face to face what his interpretation is you will both learn and the job will be safe.