Any safety pro with one week of experience in the field will understand the abuses of “extension cords.” These cords may be the most common finding of any organization, and often, the professional may not be fully versed in the OSHA and NFPA 70 requirements. So, once again, I turn to the IFC for some easy and very straightforward requirements that can be used as a “quick check” for the safe use of extension cords.
(emphasis by me)
603.6 Extension cords
Extension cords shall NOT be a substitute for permanent wiring and shall be listed and labeled in accordance with UL 817.
Extension cords shall not be affixed to structures, extended through walls, ceilings or floors, or under doors or floor coverings, nor shall such cords be subject to environmental damage or physical impact.
Extension cords shall be used only with portable appliances.
Extension cords marked for indoor use shall not be used outdoors.
603.6.1 Application and use
Extension cords shall be plugged directly into an approved receptacle, relocatable power tap or current tap and, except for approved multiplug extension cords, shall serve only one portable appliance.
603.6.2 Ampacity
The ampacity of the extension cords shall be not less than the rated ampacity capacity of the portable appliance supplied by the cord.
603.6.3 Maintenance
Extension cords shall be maintained in good condition without splices, deterioration or damage.
603.6.4 Grounding
Extension cords shall be grounded where serving grounded portable appliances.