30 CFR 57.12006 - Distribution boxes.
Distribution boxes shall be provided with a disconnecting device for each branch circuit. Such disconnecting devices shall be equipped or designed in such a manner that it can be determined by visual observation when such a device is open and that the circuit is deenergized, and the distribution box shall be labeled to show which circuit each device controls.
Title 30 published on 2015-07-01
The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 30 CFR Part 57 after this date.