fast facts 

Temporary Extension Cords and Power Connectors 

Should Not Be Used for Permanent Wiring 

January 2010 

Office of Compliance 

advancing safety, health, and workplace rights in the legislative branch 

www.compliance.gov 

Improper use of easily overloaded, unapproved extension cords can present a serious fire safety hazard in the 

workplace as well as the home. In fact, misuse of extension cords led to a significant and costly fire in an 

Executive Branch office building in 1998. The National Fire Protection Association’s report for 2008 

explains that electrical fires, electrical failures or malfunctions result in an average of 53,600 home fires each 

year. These fires caused more than 500 deaths, injured 1,400 people and 

accounted for $1.4 billion in property damage. The Bureau of Labor Statistics 

of the U.S. Department of Labor reports that during 2007, workers suffered 

1,100 electrical burn injuries and 1,480 electrical shock injuries in the private 

sector. 

Verification of a Safe Extension Cord 

Extension cords and power connectors over 50 volts must be tested and labeled 

by an Occupational Safety and Health Administration (OSHA) recognized 

testing laboratory. Approved extension cords and connectors are safe for use 

when following the manufacturer’s recommendations for brief periods of time. 

Figure 1 shows a non-compliant light duty extension cord that is not labeled by 

a laboratory and is considered unapproved. The U.S. Consumer Product 

Safety Commission (CPSC) recalls unsafe extension cords. Many are foreign made and some have counterfeit 

labels. You may wish to check the CPSC website, www.cpsc.gov, before 

making a purchase. 

Extension cords vary from light to heavy duty based on intended use 

requirements. For example, extension cords 

made with only two wires and no ground wire 

(a two prong plug) are made to power a single 

lamp with a small current load. On the other 

hand, heavy duty three wire extension cords 

grounded with multiple covering layers of insulating protective covering materials are made 

to power heavy duty tools such as those used 

in construction work. Others are made for 

temporary service, such as for holiday lighting, or powering an electrical tool that is 

moved to different locations, such as during maintenance or emergency repair work. 

There are varying regulatory requirements, depending on the use of extension cords, 

for connected cube taps (or a box with outlets), multi-taps, and other temporary wiring devices used to power grounded equipment. A ground connection is required in all of these devices in order to maintain a protective system. See Figure 3. 

Figure 1 Non-approved light-not-grounded 

duty extension cord 

Figure 3 Multi-tap and extension 

cord in use. 

Figure 2 Three prong plug into a two-wire extension cord 
Many of the extension cords being used today have built-in ground 

fault circuit interrupters (GFCIs) to enhance the user’s protection 

during emergencies, wet locations, construction and similar types of 

work. See Figures 4 and 5. If double insulated tools are used, then 

grounded temporary receptacles are not required. The NFPA’s, 

National Electrical Code (NEC) and OSHA’s electrical standards 

require electrical equipment to be approved and used in accordance 

with the agency’s 

laboratory label 

and manufacturer’s 

requirements. 

Improper Application of Temporary Wiring Devices 

The NEC and OSHA make clear that temporary electrical devices are to be removed immediately from service 

once the construction work or other purpose for using the temporary wiring is completed. Temporary wiring is not 

to be used as permanent wiring. For example, there is a 90 day limit for an extension cord and other temporary 

wiring devices used for holiday lighting at a given location, as established by the NEC and by OSHA in its electrical standards. 

Most of the temporary wiring violations identified in the Legislative Branch are found in offices, particularly in 

historic buildings with limited electrical receptacles that are often beyond the reach of appliance power cords. 

When temporary wiring is necessary, avoid using extension cords having plugs with only two prongs and connections with two slot openings when you are powering grounded electrical devices. See Figure 1 for an image of 

what to avoid. (For more information see Fast Facts on Damaged Power Cords, Power Strips & Dangerous Daisy 

Chains and GFCIs). 

Devices to Avoid for Temporary Wiring and Power Needs

Temporary wiring devices are not the solution when a permanent power supply is needed. A power strip or surge 

protector with a longer power cord could be an acceptable alternative. Two-wire extension cords are easily overloaded, causing them to get hot enough to short-circuit or ignite combustible materials in contact with them, especially those cords equipped with multiple receptacles. Light duty extension cords should never be used for powering multiple items at the same time, such as space heaters, toasters or hair dryers that have a high energy demand 

and those with exterior metal surfaces that need to be grounded. Visit the CPSC website and review the lists of 

those extension cords that have been recalled in recent years, including those with undersized electrical conductors 

and no ground connection. 

 Figure 4 Extension Cord with a “pigtail” 

 Ground Fault Circuit Interrupter 

Figure 5 Extension Cord with “built in”

Ground Fault Circuit Interrupter 
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Consumer Product Safety Commission website: 

 http://www.cpsc.gov/cpscpub/prerel/category/household.html

By visiting the above website, you can find a complete list of electrical cords that have been recalled as well as 

detailed information as to where the cords were sold, the time period, and refund or exchange policy that has been 

implemented by each manufacturer or retailer. 

 

 

This information does not constitute advice or an official ruling of the Office of Compliance or the Board 

of Directors and is intended for educational purposes only. For further information, please refer to the 

Congressional Accountability Act (2 U.S.C. 1301 et seq.) and the regulations issued by the Board, or you 

may contact the Office of Compliance.

The Office of Compliance advances safety, 

health, and workplace rights in the U.S. 

Congress and the Legislative Branch. Established as an independent agency by the 

Congressional Accountability Act of 1995, 

the Office educates employees and employing offices about their rights and responsibilities under the Act, provides an impartial 

dispute resolution process, and investigates 

and remedies violations of the Act. 

If you have any questions, please do not 

hesitate to contact the Office of Compliance: 

Room LA 200, John Adams Building 

110 Second Street, SE 

Washington, D.C. 20540 

t/ 202-724-9250 

tdd/ 202-426-1912 

Peter Ames Eveleth f/ 202-426-1913 

General Counsel 

Mary-Margaret Smith 

Editor Download the entire Fast Facts suite at http://www.compliance.gov 

Relevant OSHA and NFPA Standards 

 29 [CFR§1910.303 – Conductors and equipment are acceptable only if approved. Equipment shall be free 

 from recognized hazards. 

 29 [CFR§1910.304(b)(3)(ii) – GFCI protections apply to temporary wiring used during maintenance, 

 remodeling, repair of buildings, structures or equipment, or during similar construction-like activities. 

 29 [CFR§1910.305(a)(2) - Temporary wiring needs to protect flexible cords and cables from accidental 

 damage. 

 29 [CFR§1910.305(g)(1) – Flexible cords and cables may not be run through holes in walls, ceilings, floors, 

 doorways or windows, or concealed behind walls, ceilings, or floors. 

 29 [CFR§1910.305(a)(2)(i)(B) – period not to exceed 90 days for Christmas decorative lighting, carnivals 

 and similar purposes, relating to lighting used for specific and temporary purposes, since over time the 

 wiring can break down and become a hazard. 

Similar to the above standards of Section 590.3 (B) of the National Electrical Code NFPA 70 establishes 90 days or 

less for temporary wiring for holiday decorative lighting and power use. Construction, emergencies and similar uses 

of temporary wiring is to be removed once the work is completed as stated in section 590.3(D).