Frank: I am sure you are with your back up against the wall if the job will be in your jurisdiction, and if so, I would look at the following rules taken from the 2002 NECH and read it to be sure I was correct if I did accept the installation.
PS: I would be interested in what the author of the following book would have to say: http://www.firehouse.com/brannigan/2002/0131.html
334.10 Uses Permitted.
Type NM, Type NMC, and Type NMS cables shall be permitted to be used in the following:
(1) One- and two-family dwellings.
(2) Multifamily dwellings permitted to be of Types III, IV, and V construction except as prohibited in 334.12.
(3) Other structures permitted to be of Types III, IV, and V construction except as prohibited in 334.12. Cables shall be concealed within walls, floors, or ceilings that provide a thermal barrier of material that has at least a 15-minute finish rating as identified in listings of fire-rated assemblies.
FPN No. 1:Building constructions are defined in NFPA 220-1999, Standard on Types of Building Construction, or the applicable building code, or both.
FPN No. 2:See Annex E for determination of building types [NFPA 220, Table 3-1].
Commentary: A well-established means of codifying fire protection and fire safety requirements is to classify buildings by types of construction, based on materials used for the structural elements and the degree of fire resistance afforded by each element.
The five fundamental construction types used by the model building codes are Type I (fire resistive), Type II (noncombustible), Type III (combination of combustible and noncombustible), Type IV (heavy timber), and Type V (wood frame). Types I and II basically require all structural elements to be noncombustible, whereas Types III, IV, and V allow some or all of the structural elements to be combustible (wood).
The selection of building construction types is regulated by the building code, based on the occupancy, height, and area of the building.
The local code official or the architect for a building project can be consulted to determine the minimum allowable (permitted) construction type for the building under consideration.
When a building of a selected height (in feet or stories above grade) and area is permitted to be built of combustible construction (i.e., Types III, IV, or V), the installation of nonmetallic sheathed cable is permitted.
The common areas (corridors) and incidental and subordinate uses (laundry rooms, lounge rooms, etc.) that serve a multifamily dwelling occupancy are also considered part of the multifamily occupancy, thereby allowing the use of nonmetallic sheathed cable in those areas.
If a building is to be of noncombustible construction (i.e., Type I or II) by the owner's choice, even though the building code would permit combustible construction, the building is allowed to be wired with nonmetallic sheathed cable.
In such an instance, nonmetallic sheathed cable may be installed in the noncombustible building because the Code would have permitted the building to be of combustible construction.
Annex E provides charts and other explanatory information to assist the user in understanding and categorizing the exact types of construction under consideration.
A table to cross reference building types to the various building code types of construction is provided in Annex E also.
[This message has been edited by Joe Tedesco (edited 07-12-2002).]