Grounded and equipment grounding conductors must each be identifiable and distinguishable from other conductors, polarity may not be reversed, and grounding terminals on receptacles, cord connectors and plugs are used only for grounding. Ground-fault protection: the employer must protect workers on construction sites by one of two methods, in addition to any other equipment grounding rules. Under the first, every 15- or 20-ampere, 120-volt, single-phase receptacle outlet on the site that is not part of the building's permanent wiring and is in use by workers has an approved ground-fault circuit interrupter (exempt: receptacles on a single-phase, two-wire generator, portable or vehicle-mounted, rated 5 kW or less whose circuit conductors are insulated from the frame and all other grounded surfaces). Under the second, the employer establishes and implements an assured equipment grounding conductor program covering all cord sets, receptacles not part of the building, and cord-and-plug equipment available for or used by workers. That program needs a written description of the specific procedures, available at the jobsite for OSHA and any affected employee to inspect and copy; one or more designated competent persons to run it; a visual inspection before each day's use of each cord set, plug, receptacle and cord-connected item (except fixed ones not exposed to damage) for external defects and signs of internal damage, with damaged items kept out of use until repaired; continuity tests of all equipment grounding conductors and tests that each receptacle and plug has the grounding conductor on its proper terminal; tests before first use, before return to service after repair, after any incident reasonably suspected of causing damage such as a cord being run over, and at intervals not over 3 months (6 months for fixed cord sets and receptacles not exposed to damage); no use of equipment that has not passed; and a record of the tests identifying each item passed and the last test date or interval, kept by logs, colour coding or other effective means until replaced by a newer record and available at the jobsite. Outlet devices are rated at least for the load, a single receptacle on an individual branch circuit at least the circuit rating, multiple receptacles per Table K-4 (15 A circuit: 15 A max; 20 A: 15 or 20; 30 A: 30; 40 A: 40 or 50; 50 A: 50), and motor plugs without individual overload protection no more than 15 A at 125 V or 10 A at 250 V. Outdoor open conductors of 600 volts or less meet climbing space (24 or 30 inches) and ground clearances of 10 feet over grade, sidewalks or reachable platforms, 12 feet over non-truck vehicle areas, 15 feet over truck traffic areas and 18 feet over public roads, streets, alleys and driveways; 3 feet from windows, doors and fire escapes; and roof clearances of 8 feet (insulated), 10 feet (covered) or 15 feet (bare) with listed reductions. Outdoor lamps sit below live parts unless lockable disconnects or other safeguards exist. Service disconnects are provided, show open or closed, sit at the readily accessible point nearest entry and open all ungrounded conductors together; services over 600 volts have guarded open wires and high-voltage warning signs. Overcurrent protection matches conductor capacity, does not open the grounded conductor alone, uses disconnecting means for accessible cartridge fuses and fuses over 150 volts to ground, is readily accessible and away from damage and ignitable material, is shielded, breakers show on or off with up as on for vertical handles and SWD marking for fluorescent switching; branch circuits and feeders above 600 volts have short-circuit protection. Grounding rules cover which systems are grounded, separately derived systems, portable and vehicle generators, grounding connections, a permanent continuous path, enclosures and fixed and cord-connected equipment to be grounded (hand-held motor tools, equipment in wet locations, hand lamps, with double-insulated and isolating-transformer exceptions, double-insulated tools being distinctively marked), grounding methods, bonding, made electrodes (a single rod, pipe or plate over 25 ohms augmented by another at least 6 feet away) and high-voltage portable equipment (impedance-grounded neutral, ground fault relaying, continuity monitoring, electrode separated by at least 20 feet).
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.