If they are enforcing Class 1 Div 2 you will still need seal offs on the outside and RMC/IMC on the inside. I would ask the AHJ how they want to deal with the penetrations.
I agree that i need seal offs and IMC or RMC inside but if i do conduit on the outside i am eliminating about 90% of the rigid conduit.
I will check with AHJ on sealing requirements.
Thanks all for your replies.