I know 334.30(B)(1) (quoted below) has been discussed here before, but I haven't seen a satisfying answer to my particular question.
I recently had a discussion with an inspector about the requirement to staple NM cable that has been fished through a finished wall to an existing junction box. My interpretation of 334.30(B)(1) was that it creates an exception for the requirement to staple cables to studs when fishing them through finished walls. The inspector, however, pointed out 334.30(B)(1) provides an exception for support only. Since no explicit exception is made for securement, he contends drywall must be removed to secure the cable with staples.
Although I think most of us would consider his interpretation pedantic and perhaps overzealous, it's hard to argue his interpretation is wrong because that's indeed how it's written. However, requiring securement also creates a de facto requirement for support because all methods of securement also provide support. Thus, creating an exception for support that still requires securement provides no actual exception for support. 334.30(B)(1) would be completely moot under his interpretation.
So, that raises the question why does 334.30(B)(1) exist if it doesn't mean anything?
I think the simplest explanation is the NEC probably intended "unsupported" to mean "unsupported and unsecured" in 334.30(B)(1), but I have no proof of that. If that is the case, it would be nice if they would revise it to be clearer.
What do you guys think?
Section 334.30 from the 2020 NEC follows:
334.30 Securing and Supporting
Nonmetallic-sheathed cable shall be supported and secured by staples, cable ties listed and identified for securement and support, or straps, hangers, or similar fittings designed and installed so as not to damage the cable, at intervals not exceeding 1.4 m (41/2 ft) and within 300 mm (12 in.) of every cable entry into enclosures such as outlet boxes, junction boxes, cabinets, or fittings. The cable length between the cable entry and the closest cable support shall not exceed 450 mm (18 in.). Flat cables shall not be stapled on edge.
Sections of cable protected from physical damage by raceway shall not be required to be secured within the raceway.
(A) Horizontal Runs Through Holes and Notches
In other than vertical runs, cables installed in accordance with 300.4 shall be considered to be supported and secured where such support does not exceed 1.4-m (41/2-ft) intervals and the nonmetallic-sheathed cable is securely fastened in place by an approved means within 300 mm (12 in.) of each box, cabinet, conduit body, or other nonmetallic-sheathed cable termination.
Informational Note: See 314.17(B)(1) for support where nonmetallic boxes are used.
(B) Unsupported Cables
Nonmetallic-sheathed cable shall be permitted to be unsupported where the cable:
(1) Is fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable.
(2) Is not more than 1.4 m (41/2 ft) from the last point of cable support to the point of connection to a luminaire or other piece of electrical equipment and the cable and point of
connection are within an accessible ceiling in one-, two-, or multifamily dwellings.
(C) Wiring Device Without a Separate Outlet Box
A wiring device identified for the use, without a separate outlet box, and incorporating an integral cable clamp shall be permitted where the cable is secured in place at intervals not exceeding 1.4 m (41/2 ft) and within 300 mm (12 in.) from the wiring device wall opening, and there shall be at least a 300 mm (12 in.) loop of unbroken cable or 150 mm (6 in.) of a cable end available on the interior side of the finished wall to permit replacement.