Use of any electrical equipment such as underwater lights, deck lights, the pool pump or any other accessory can pose a safety threat to people in the water if the wiring is incorrect or faulty. Use the following safety precautions to avoid electrocution or electrical shock:

Always use a trained technician for installation, service or repair of any electrical wiring or equipment. Have your technician verify these points:

Use ground fault circuit interrupters (GFCI) for the power supply circuit for each piece of electrical equipment, including utility pumps to drain the pool water. The GFCI will disconnect the power supply if any electricity leaks are detected.
Make sure your installation meets all local and national codes.
Make sure all electrical equipment is grounded and all metal objects (ladders, diving platforms, etc.) are electrically bonded together.

Never use extension cords around a pool or spa.
Never enter the water when a utility pump is running.
Never put an aluminum vacuum handle into the pool.
Never swim in your pool or spa during an electrical storm.