2002 NEC: "406.3(D) Replacements. Replacement of receptacles shall comply with 406.3(D)(1), (2), and (3) as applicable.
(1) Grounding-Type Receptacles. Where a grounding means exists in the receptacle enclosure or a grounding conductor is installed in accordance with 250.130(C),
grounding-type receptacles shall be used and shall be connected to the grounding conductor in accordance with 406.3(C) or 250.130(C).
(2) Ground-Fault Circuit Interrupters. Ground-fault circuit-interrupter protected receptacles shall be provided where replacements are made at receptacle outlets that are required to be so protected elsewhere in this Code.
(3) Nongrounding-Type Receptacles. Where grounding means does not exist in the receptacle enclosure, the installation shall comply with (a), (b), or (c).
(a) A nongrounding-type receptacle(s) shall be permitted to be replaced with another nongrounding-type receptacle(s).
(b) A nongrounding-type receptacle(s) shall be permitted to be replaced with a ground-fault circuit interrupter type of receptacle(s). These receptacles shall be marked â€śNo Equipment Ground.â€ť An equipment grounding conductor shall not be connected from the ground-fault circuitinterrupter-type receptacle to any outlet supplied from the
ground-fault circuit-interrupter receptacle.
(c) A nongrounding-type receptacle(s) shall be permitted to be replaced with a grounding-type receptacle(s)where supplied through a ground-fault circuit interrupter.
Grounding-type receptacles supplied through the ground fault circuit interrupter shall be marked â€śGFCI Protectedâ€ť and â€śNo Equipment Ground.â€ť An equipment grounding
conductor shall not be connected between the grounding type receptacles."