Electrical Conduit Inside My Food Truck

I am converting my 1973 Airstream into a Fry Bread Concession Trailer and I am running the electrical today.  I have mounted my 100 amp service box inside and Im getting ready to mount my electrical boxes inside the trailer in the various locations needed.  My question is : What type of external conduit can I use?
Does it need to be EMT steel electrical conduit,  or can I use some other type such as steel flex or plastic electrical condut ridgid/ flexable such as seal tight.  Im in Phoenix Arizona  Any sugesstions?
Thx John

I was viewing Youtube videos of truck builds and saw steel flex conduit being used, this would work nice for me because all the surfaces in the airstream are curved and this would make it mouch easier then bending conduit.  Any ideas?
Thx
John

Your local codes prevail. Unless someone on here lives in your city, county, or state and even then I'd not trust their call. Save yourself some money and lots of work and wait until tomorrow and make some phone calls then you'll know the answer is correct. Some health departments insist on a blueprint before approving any build. So check with what ever authority is necessary before you proceed.
good luck
jack

You might want to check out cable tray, or cable duct, cable raceway, or sometimes called power poles.  They allow you to run cabling of different types and gauge thru one duct that can be closed off.  Especially in environments where you want even smooth surfaces for cleaning these systems works well.  The flex type conduit with its corrugated outer surface to me would not be a choice as its not easy to keep clean, but then again your right about running along curved surfaces, its much more difficult with a rigid conduit.  Of coarse all this is dependent on the whims for your local inspectors and codes.  But I hate exposed cluttered surfaces, just more places for dirt and grease to hide.