Whenever I find something like that I explain the differences and possibilities to the client.
And this goes in the report…
TWO- and THREE-HOLE RECEPTACLES
**The use of three-hole ground-type receptacles on a two-wire electrical system gives the impression that safety protection is present in the circuit, when in reality it is not. Older style two-hole receptacles are still available and should be installed to eliminate this false sense of security. Three-hole receptacles may be more convenient (and often less expensive), but are often installed without giving consideration to this situation. **
**The use of a three-pronged plug in an ungrounded receptacle can be a safety concern. The plug has the grounding provision for a reason and electrical appliances should always be used for the function they were intended to perform. **
**All such installations should be labeled “No Equipment Ground” on each receptacle that applies. **Grounding of all “three-pronged” receptacles or protection with a Ground Fault Circuit Interrupter (GFCI) on each is recommended for safety reasons, prior to the close of escrow or after taking possession of the property.
**“Two-hole” outlets are not grounded and should never be used with a “three-pronged” plug. Adapters have been devised for this usage, but there is still no adequate ground and such adapters are not always safe. Until the electrical system is upgraded for “three-pronged” usage, it would be prudent to not use adapters, extension cords, or “three-pronged” plugs in any way. Consider that “three-pronged” plugs have been engineered for use with a “three-hole” grounded receptacle. **