Whether installing a new light fixture or working on existing electrical components, any home improvement project involving electricity should be performed safely. It is important to determine whether wires are live when working with electricity. The easiest way to do this is to purchase a live-wire tester, available at hardware stores for around $10 as of 2009.

Test the Tester

Checking your neon tester each time you use it is vitally important. This ensures the tester is functioning properly. Start by checking a wall socket that you know to be live. Take one of the tester wires in each hand. Make certain your hand remains on the insulated plastic portion and gently place the tester wires in each slot of the socket. It does not matter which wire you place in which slot. If your neon tester lights up, it is working properly. If your tester does not light up, then you need to replace it before moving on to further projects.

Initial Test

Equipped with a working tester, you are now ready to begin checking for a live wire. If checking for electricity in a wall plug-in or light fixture, this can sometimes be accomplished without removing the fixture. Simply place the tester wires into the plug-in slots or area around the light fixture where a bulb is screwed into. If the tester does not light up, this still doesn't mean that you do not have a live wire present. Further testing will need to be done inside your walls.

Further Testing

If you are testing wires surrounding a light fixture, unscrew the socket base plate and pull the fixture out of the wall so that it is hanging by it's wires. When testing a plug-in, unscrew the face plate and pull the plug-in out from inside the box where it is positioned. Once outside the wall, test the area where the wall go into the fixture or the plug-in from behind. Place one testing wire on the copper ground wire and the other testing wire on an exposed wire. Repeat this process until all of the exposed wires leading into the fixture or plug-in have been checked. If the neon tester lights up at any point, the circuit is live and you should stop working immediately until you are certain it has been turned off.

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Testing for Live Wires