Extension Cords Are Not All-Purpose Outlets: Avoid Bundling, Daisy-Chaining, and Overloading in Household Electrical Use

Extension cords are commonly used in many homes, offices, stores, and workplaces. When there are insufficient wall outlets or an appliance is located far from an outlet, extension cords provide genuine convenience. However, an extension cord is not an all-purpose outlet. Improper use may instead create hidden electrical safety risks.

The Bureau of Standards, Metrology and Inspection (BSMI), Ministry of Economic Affairs, and Xiao An Xin remind consumers that extension cords are commodities subject to mandatory inspection. When purchasing one, consumers should confirm that the Commodity Inspection Mark is displayed and check whether the Chinese-language labeling on the packaging or product itself is complete. During use, consumers should also avoid bundling, daisy-chaining, overloading, and connecting high-power appliances to reduce the risks of overheating, short circuits, and fire.

Look for the Commodity Inspection Mark When Purchasing an Extension Cord

Extension cords are subject to requirements concerning current-carrying capacity, outlet construction, wire insulation, heat resistance, fire resistance, and safe use. The ability to conduct electricity alone does not mean that a product is safe. When purchasing an extension cord, consumers should first confirm that the Commodity Inspection Mark is displayed on the product itself or its packaging and check that clear Chinese-language labeling is provided.

Consumers should also check whether information such as the company name, address, telephone number, model number, rated voltage, rated current, rated power, and precautions for use is complete. Products from unknown sources, with unclear labeling, unusually low prices, or whose completion of the inspection procedures cannot be confirmed should not be purchased or used.

Do Not Use an Extension Cord as a Long-Term Power Source for High-Power Appliances

Extension cords are primarily intended to extend the distance to a power source or temporarily provide additional connections for electrical appliances. They are unsuitable for carrying high-power electrical loads for extended periods. High-power products such as hair dryers, ovens, space heaters, induction cooktops, microwave ovens, electric kettles, and dehumidifiers may require substantial current during operation. Using such products with an extension cord may cause the extension cord to overheat or exceed its rated load.

If an extension cord must be used, confirm that its rated capacity is sufficient and avoid operating multiple appliances simultaneously from the same extension cord. If the extension cord or plug exhibits abnormal heat, a burning smell, deformation, discoloration, or a loose outlet, stop using it immediately.

Do Not Use an Extension Cord While It Is Coiled or Bundled

For cable management, many people coil or bundle excess extension cord or place it under furniture. However, doing so may interfere with heat dissipation. Extension cords generate heat while carrying electricity. If the cord is bundled or covered, heat cannot dissipate effectively, potentially causing thermal deterioration of the insulation and increasing the risks of short circuits and fire.

When using an extension cord, spread the cord out appropriately and avoid placing it under heavy objects, trapping it beneath furniture, covering it with a carpet, or placing it near high temperatures, moisture, grease, or flammable materials. The cord should also no longer be used if its outer insulation is damaged, hardened, cracked, or visibly creased.

Do Not Daisy-Chain Extension Cords

Connecting one extension cord to another may appear convenient, but it can cause users to overlook the total electrical load. If several appliances are connected after multiple extension cords have been daisy-chained, the arrangement may result in concentrated current, overheated connection points, or excessive loads on the wiring.

Daisy-chained multi-outlet extension cords are particularly common in offices, stores, exhibition venues, event sites, and temporary work areas. Although this practice may appear to solve a shortage of outlets temporarily, exceeding the safe load may cause outlets to melt, circuit breakers to trip, or even a fire.

Moist Environments and Contaminated Outlets Also Increase Risks

If dust, lint, hair, or grease accumulates on plugs and outlets over extended periods, moisture may cause electrical tracking through the accumulated contaminants or create a risk of short circuits. Extension cords should therefore not be placed in bathrooms, beside kitchen sinks, outdoors where they are exposed to rain, beside aquariums, or in other locations prone to moisture.

Consumers should also regularly check whether plugs and outlets are clean and secure. If charring, looseness, green corrosion, unusual odors, or abnormal heat is found, stop using the product immediately and replace it. Do not disassemble or modify it or continue using it despite the abnormality.

Safe Use Reminders

Action Technology recommends that consumers follow the following basic principles when using extension cords to reduce electrical risks in homes and offices.

• Look for the Commodity Inspection Mark: When purchasing, confirm that the Commodity Inspection Mark is displayed on the extension cord itself or its packaging and check that the Chinese-language labeling is complete.
• Do Not Overload the Extension Cord: Confirm the rated current and power before use and avoid connecting multiple high-power products simultaneously.
• Avoid Connecting High-Power Appliances to Extension Cords: Products such as hair dryers, ovens, space heaters, induction cooktops, and electric kettles should be connected directly to fixed wall outlets.
• Do Not Bundle or Cover the Cord: Allow adequate space for heat dissipation while the extension cord is carrying electricity, and avoid coiling, crushing, covering, or placing it near a heat source.
• Do Not Daisy-Chain Extension Cords: Avoid connecting one extension cord to another to reduce the risks of overloading and overheated connection points.
• Keep Plugs and Outlets Clean: Regularly remove dust and contaminants, and avoid using extension cords in moist, high-temperature, or flammable environments.
• Stop Use Immediately If an Abnormality Occurs: If a burning smell, abnormal heat, deformation, looseness, damage, or circuit breaker trip occurs, unplug and replace the extension cord immediately.

Small Electrical Accessories Also Require Proper Use

Although extension cords are small accessories commonly used in everyday life, they are closely related to household electrical safety. Looking for the Commodity Inspection Mark when purchasing and avoiding bundling, daisy-chaining, overloading, and moist environments during use allows extension cords to provide convenience while reducing the risks of fire and electric shock.

Action Technology Co., Ltd. reminds consumers that whether electrical products and equipment are used in homes, offices, stores, or small workplaces, attention should be given to product safety labeling and proper methods of use. Good purchasing and operating habits help make everyday electrical use safer.

Sources: Bureau of Standards, Metrology and Inspection, Ministry of Economic Affairs – Xiao An Xin｜Extension Cord Safety Reminder
Keelung Branch, Bureau of Standards, Metrology and Inspection｜How to Select and Use Extension Cords for Safer Homes