FAQ

Revision/New

305 General Requirements – Systems

Over 1000V ac/1500V dc

Leviton Comment: Article 305 is covered with Article

245 on page 57.

Revision/New

310.3(A)(B) Reconditioned Equipment

Leviton Comment: Article 310.3(A)(B) is covered with

Article 210.23(A) found on page 26.

Revision/New

312.10, 314.5 Screws Protruding into

Boxes – How Much is Allowable

Leviton Comment: We are covering Articles 312.10

and 314.5 together because they are very similar, and

both relate to screws protruding into boxes.

Change Summary

• The NEC has set limits on how far screws can protrude

into boxes.

Article 312 – Cabinets, Cutout Boxes, and Meter Socket

Enclosures

312.10 Screws or Other Fasteners. Screws or other

fasteners installed in the eld that enter wiring spaces shall

be as provided by or as specied by the manufacturer or

shall comply with the following as applicable:

(1) Screws shall be machine type with blunt ends.

(2) Other fasteners shall have blunt ends.

(3) Screws or other fasteners shall extend into the enclosure

no more than 6 mm (1⁄4 in.) unless the end is protected with

an approved means.

Exception to (3): Screws or other fasteners shall be permitted to extend into

the enclosure not more than 11 mm (7⁄16 in.) if located within 10 mm (3⁄8 in.)

of an enclosure wall.

Article 314 – Outlet, Device, Pull, and Junction Boxes;

Conduit Bodies; Fittings and Handhole Enclosures

314.5 Screws or Other Fasteners. Screws or other fasteners

installed in the eld that enter wiring spaces shall be as

provided by or specied by the manufacturer or shall

Material taken from the National Electric Code

is reprinted with permission

from NFPA 70

, 2023 edition. National Electrical Code

NEC

Text