Re: Legal or not?
It doesn't boil down to whether the building is industrial, commercial or residential, but rather what types of materials are required to be used to construct the building. Buildings are allowed to be constructed with certain types of materials, depending on the size, height, and use of the building. It also depends on whether or not fire sprinklers are used and fire department access to the building perimeter. That said, it often will happen that industrial occupancies require a very large building, and therefore must be constructed of steel and/or masonry alone. These are type I and II buildings. Section 334.10 does not allow the use of NM in types I and II buildings. This is not to say that if a building is constructed of steel and/or masonry, NM cannot be used, but rather to say that if a building is required to be built with steel or masonry only (type I or II), then NM cannot be used.
What about your building? Did the building official allow the use of wood partition walls? If he did, then NM may be used. If not, then, probably, you may not use NM. See Annex E, for the rules (combustible means wood).