Use only U.L. approved tree lights. Check for frayed or bare wiring, lights with cracked or broken sockets or loose connections. If they show signs of wear and tear, do not use them. Avoid the use of extension cords. Never run an electrical cord under carpeting.
Decorations can cause overloaded circuits.
Watch for signs of lights dimming. Turn off all lights when leaving the house or when retiring for the night. Never burn your tree in your fireplace.