You tested electrical wires to be sure they're not hot, but are you certain your tester is functioning properly? There are a number of ways to test a wire to see if it's "live" with electricity. One common method is plugging in a light bulb. If it lights, then it's live; if not, it's dead. That's simple enough, agreed? Another common practice involves using a tester before any work begins. Usually, these techniques work well, but every so often things fail and the handyman or contractor gets a nasty shock. Why? While they tested, as they should have, they did it only once, not knowing for certain if the tester itself was working. What if the bulb burned out? Or the tester failed? Everything would seem to be OK to go, but no, the wires might still be hot, and one wouldn't know it until too late. Our advice? Test twice; make sure things are working first, then make your splice. And that's the On The House tip for today.