This proposal is a result of the following discussion. Comments are welcome.
Substantiation:Branch circuits originating in each dwelling unit shall supply only loads within that dwelling unit or loads associated with that dwelling unit. Branch circuit wiring associated with each dwelling unit shall not pass through another dwelling unit, except within adjoining walls or common areas such as attics, crawl spaces, or mechanical chases.
It is not clear whether multi-family dwelling units can comply with the present wording of this article. It may be interpreted that in the context of this article, the wall that adjoins two units is ?in? both units. Thus, if there is a circuit originating in Unit A and serving a receptacle in Unit A side of the common wall, the conduit within the common wall is ?in? Unit B, in violation of this article. Since 210.52 would require receptacles on both sides of the common wall, there is an unresolvable conflict within the NEC.
There are two separate concerns involved in this article. One concern is that a tenant wishing to turn off an outlet for repair or maintenance should not have to go into a neighbor?s unit to find the breaker serving that outlet. The other concern is that a tenant wishing to remodel their unit, including the removal of an internal wall, should not encounter a conduit from a circuit that originates and terminates within a neighbor?s unit, but that passes through their unit. The proposed revision clearly prohibits both situations.