In industrial laboratories, receptacles within 6 ft of a sink that supply equipment where removal of power would create a greater hazard are not required to have GFCI protection if they meet which rating criteria?

• A. Single-phase 150V to ground or less, 50A or less
• B. Three-phase 150V to ground or less, 100A or less
• C. Both A and B
• D. Neither A nor B

Answer: (C)

The key idea is that there is an exception to the GFCI requirement for receptacles located near a sink in industrial labs, but only for certain circuit ratings. If the receptacle is on a single-phase circuit with a voltage to ground of 150V or less and a current rating of 50A or less, it is not required to have GFCI protection. Similarly, if the receptacle is on a three-phase circuit with a voltage to ground of 150V or less and a current rating of 100A or less, it is also not required to have GFCI protection. Since either of these conditions meets the exemption, both categories qualify, confirming that the correct interpretation is that either rating criterion allows the receptacle to remain without GFCI protection in that near-sink lab setting.

In practice, this means small single-phase outlets up to 50A and typical three-phase outlets up to 100A near sinks can be left without GFCI protection, provided the voltage to ground is within the 150V limit and the location and use fit the specified context. Outside those ratings, GFCI protection would be required.