A frayed or cracked cord could cause a shock or fire. Replace old or damaged extension cords with new ones certified by an independent testing laboratory. Check to see that extension cords are not overloaded, as noted by the ratings labeled on the cord and appliance.
Overloaded cords can cause a fire.
Change cords to higher-rated cords or unplug some appliances. Extension cords are designed for short-term use, and not intended as permanent household wiring. Test GFCIs monthly to make sure they are working properly. Check the wattage of all light bulbs in light fixtures to make sure you are using the correct wattage. Using a bulb with a higher wattage than recommended can cause the fixture to overheat and create a fire.