What is not required for a duplex grounding-type receptacle installed under the sink for a dishwasher?

In a residential setting, a duplex grounding-type receptacle installed specifically for a dishwasher under the sink typically does not require Ground Fault Circuit Interrupter (GFCI) protection. This is because dishwashers are generally classified as fixed appliances that are hardwired to the electrical system or plugged into a receptacle that is not readily accessible. The National Electrical Code (NEC) specifies that GFCI protection is required for receptacles in damp or wet locations, such as those in kitchens or bathrooms; however, since a dishwasher receptacle is often located in a less accessible location and may be protected by GFCI elsewhere in the circuit, it may not be mandated at the receptacle under the sink.

In contrast, surge protection is important for devices that could be susceptible to voltage spikes, but it's not a specific requirement for the receptacle itself. Weatherproofing is also not necessary for an indoor appliance like a dishwasher, where exposure to elements is controlled. Grounding is a critical safety component that ensures any electrical faults are safely redirected, reducing the risk of shock or fire.