Safety rules and practices to avoid electrical shock?

An important safety precaution you should take before starting any electrical servicing job is to make sure that the circuit is grounded, and not grounding through your body.

If you stand on a cement floor while wearing leather soled shoes, and touch a water or gas pipe, a TV antenna, or any grounded object, or a "hot" wire, you can get a severe shock. A way to prevent yourself from being grounded is to wear rubber soled or composition soled shoes. The only way to be completely safe while working on a small appliance is to unplug it.