I live in Sparks, Nevada, and the 2011 National Electrical Code applies to me. My work will be inspected when complete.
I am replacing a switch and have found that someone before me (accidentally?) sliced open the insulation on the hot wire for the switch and neglected to fix it.
The slice only goes down a few inches of the wire, so I am considering cutting this off and just adding a jumper wire to it to extend it the required three inches outside the box (there will be enough wire to add a nut). Is this legal (per NEC 2011)? Specifically I am unsure if this a violation of the amount of wire I have to have coming in to the box.
See picture below, the slice is visible in the hot wire. It only goes as far as you can see in the picture and is intact after that.
Edit: Or should I just wrap it in electrical wire rated for at least 120V? My understanding is this is legal because it is in a junction box.