We are putting a stick built office in our industrial maintenance building for the new maintenance manager. (10' X 12' one story) Can we use NM cable or do I need to use metalic flex?
You may/may not, depending on what code you are on. The '02 and '05 have restrictions on installing it in type 3,4,5 construction. Take a look at 334.10 (3) and focus on the word/definition of concealed.
I am not familiar with the requirements of Type 3,4,5 construction. You might be able to use Romex.
It just seems like the thing to do inside an industrial bldg., is to use EMT/Greenfield/MC Cable as the wiring method.
We dont keep Romex & its fittings on hand, but have plenty of the other stuff.
Factories that have nonhazardous atmospheres ( such as not not explosionproof ) are still allowed to use open wiring on insulator if it is out of reach. You can still use open wiring as a cheap alternative to busway.
1996 and earlier NEC allowed NM, UF, and SE cable for exposed work in factories if it was protected from mechanical damage if within reach of people of mobile machines.
In an electroplating circuit I can theoretically stick THWN-2 into a cable tray which is a theoretically easy way to do such a high current circuit.