How Permanent is your Wiring? Hidden Risks of Extension Cord Use

Extension cords aren’t a replacement for an outlet with permanent wiring, and can actually be a major safety hazard. 

Quick Facts:

The leading cause of residential fires are electrical issues, and reports of fires and fatalities due to extension cord misuse are increasing in Ontario (ESA)

Extension accords are listed as the top of 6 common causes of electrical fires in Ontario on the Ontario Association of Fire Chiefs

These cords are not designed for permanent use, they are designed to provide a temporary wiring solution, as they lack the heavy-duty insulation and protective casing required for permanent wiring. Extension cords do not replace the need for a properly installed outlet.

The primary hazards include:

• Fire Hazard from Overheating: Extension cords often have thinner wires than permanent house wires. With continuous high power draw that these cords are not designed for, heat can build up, potentially melting the plastic insulation and increasing the risk of nearby materials like wood or carpet igniting. 

• Insulation Degradation or Loose Connection: Unlike permanent wiring which are protected inside walls, extension cords are exposed to physical wear. Constant walking, pinching under furniture, or exposure to UV light and moisture causes the insulation to crack, leading to exposed live wires and electrical arcs, which is a dangerous, high-temperature discharge that can reach 35,000°F. Walking on, tripping, or repeated movement of the cord can also loosen the cord's connection in the outlet, which is another risk for electrical arcs.

• Voltage Drop and Appliance Damage: Long cords create electrical resistance, causing a "voltage drop." This can cause motors in appliances like refrigerators or air conditioners to work harder, leading them to overheat and burn out prematurely.

• Hidden Dangers Under Rugs: To make permanent cords less visible, people often run them under rugs or through walls. This prevents heat from dissipating and makes it impossible to see when the cord is fraying or damaged.

• Physical Safety Risks: Permanently installed cords create constant tripping hazards in high-traffic areas, which can lead to falls or cause the cord to be yanked, damaging the outlet and the plug.

• Legal and Insurance Risks: Using extension cords as a permanent wiring solution is a violation of the Ontario Electrical Safety Code (OESC) if it is used for permanent wiring rather than temporary purposes, or if it is misused (e.g., overloaded, damaged, or hidden under rugs). Extension cords are meant for temporary, portable, and light-load use only. If a fire occurs, insurance companies may deny claims due to improper use of equipment.

• Safety Recommendation: If you find yourself relying on an extension cord daily, you should have a licensed electrician install a permanent wall outlet at that location.

Extension Cord Safety Tips

• Keep power bars and cords away from moist or wet environments. Keep weather-proofing covers closed on all outdoor outlets.

• Make sure there is enough space behind couches, bookcases, beds, desks and countertop appliances to ensure plugs are not pushing against walls, as this can cause damage.

• Keep cords away from carpets. Running a cord under a carpet may keep it out of sight, but it also keeps it from properly cooling and makes it easy to damage by foot traffic or furniture.

• Keep cords free and clear of combustible materials. Do not place boxes or furniture on the cords either.

• Keep animals away. Do not let your pets or mice chew on cords. 

• Inspect regularly. Check for nicks, damage or signs of overheating at the plug connections. Replace damaged cords. Never patch power and extension cords. 

• Use as intended. Extension cords are classified as temporary wiring. Do not drape wiring over nails or affix extension cords to walls to create an extra outlet. Instead, get a permanent outlet installed by an electrician. Avoid long runs and daisy chaining multiple cords together. A heavy duty cord is always a safer bet.

(ESFI Reaching to Safety)

For more safety tips visit: https://esasafe.com/assets/files/esasafe/pdf/Electrical_Safety_Products/Flash_Notices/19-19-FL.pdf