I've been an industrial elecrician in Canada for many years and I am well aware of the sheath voltage issues with single conductor metal sheathed cables...and the preventive measures used to make things safer. I was recently questioned on using "one conductor only" in an NMD 14-2 cable in a house. I'm embarrased to say that I've never heard that this was not allowed. I can find a number of references to it when googling, and it appears it may be in the NEC. Can anyone tell me if this is a well known rule among all electrical contractors in the US...and if any Canadians are watching...is this in our CEC somewhere...specifically for residential wiring? Never too old to learn. sleep Thanks!!