Use of Flexible Electrical Cords
Flexible electrical cords are used today in nearly every retail store, business office, factory or construction site. Once they're in use, few people notice them. But I do as a safety and health consultant. That's because flexible electrical cords are a potential hazard.
Their most common application is found in electrical extension cords and power strips used with portable electrical power tools-- drills, saws, and grinders--or office equipment like computers, copiers, fax machines. Even in manufacturing, flexible electrical cords are used to connect medium and small size equipment to a power source. In some instances this is an acceptable practice.
While there are many acceptable uses of flexible electrical cords, there are many misuses as well. One of the most common occurs in the absence of enough electrical outlets to connect all equipment in use. In these cases, I see electrical extension cords run up building walls, over and around piping, through walls and above drop ceilings. This can create potential electrical hazards like electrical fires, electrical shock and even electrocution. Simply stated, most flexible cords are not designed, manufactured, or approved as a substitute for the fixed wiring of a building or structure. If additional electrical outlets are required, a qualified electrician should install them where they are needed. In the long run, this is more economical and safer than running extensions cords throughout your facility.
Here is a listing of flexible electrical cord applications that are permissible by OSHA:
- In drop pendants
- For wiring fixtures
- To connect portable lamps and appliances
- To power portable and mobile signs
- Elevator cables
- For wiring cranes and hoists
- To connect stationary equipment to facilitate their frequent interchange
- To prevent the transmission of noise or vibration
- In appliances where the fastening means and mechanical connections are designed to permit removal for maintenance and repair
- In data processing where the cables are approved as a part of the data processing system
- To connect moving parts
- As temporary wiring
Temporary wiring is used during the remodeling, maintenance or repair of buildings, structures or equipment, and similar activities. Temporary wiring can also be used for holiday decorative lighting, carnivals and other similar purposes (for a period not to exceed 90 days); and for experimental or development work and during emergencies.
When flexible electrical cords are used to connect portable lamps and appliances, stationary equipment or for temporary wiring, the cord must be equipped with an attachment plug and be plugged into an approved receptacle outlet.
Other restrictions on the use of flexible electrical cords include:
- Flexible electrical cords and cables must be protected from accidental damage, as might be caused, for example, by sharp corners, projections and doorways or other pinch points.
- Flexible cords may be used only in continuous lengths without splice or tap. (Hard-service cord and junior hard-service cord No. 14 and larger may be repaired if spliced so that the splice retains the insulation, outer sheath properties, and usage characteristics of the cord being spliced.)
- Flexible cords and cables must be connected to devices and fittings so that strain relief is provided that will prevent pull from being directly transmitted to joints or terminal screws.
- Flexible cords and cables must be approved for conditions of use and location. This is important to consider when using flexible cords in potentially wet areas like pools, fountains, car washes, or in harsh working environments like construction sites.
Except in the above applications, flexible electrical cords and cables may not be used in the following ways:
- As a substitute for the fixed wiring of a structure
- Where run through holes in walls, ceilings or floors
- Where run through doorways, windows or similar openings
- Where attached to building surfaces
- Where concealed behind building walls, ceilings, or floors
- Where installed in raceways, except as otherwise permitted in certain instances
Remember these guidelines when using flexible electrical cords and cables. They will help keep your building, equipment and people safe from electrical hazards. For more information about flexible electrical cords and other electrical hazards, or to request a free on-site consultation to assess your current electrical safety condition, contact the USF SafetyFlorida consultation program at 1-866-273-1105 or visit us online at www.safetyflorida.usf.edu.