30 CFR §18.42
Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
- (a)A cable passing through an outside wall(s) of a distribution box shall be conducted either through a packing gland or an interlocked plug and receptacle.
- (b)Short-circuit protection shall be provided for each branch circuit connected to a distribution box. The current-carrying capacity of the specified connector shall be compatible with the automatic circuit-interrupting device.
- (c)Each branch receptacle shall be plainly and permanently marked to indicate its current-carrying capacity and each receptacle shall be such that it will accommodate only an appropriate plug.
- (d)Provision shall be made to relieve mechanical strain on all connectors to distribution boxes.