Flexible cords and cables shall be approved for conditions of use and location.
If used as permitted in paragraphs (g)(1)(ii)(C), (g)(1)(ii)(G), or (g)(1)(ii)(I) of this section, the flexible cord shall be equipped with an attachment plug and shall be energized from an approved receptacle outlet.
Unless specifically permitted otherwise in paragraph (g)(1)(ii) of this section, flexible cords and cables may not be used:
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 concealed behind building walls, ceilings, or floors; or
Where installed in raceways, except as otherwise permitted in this subpart.
Flexible cords used in show windows and showcases shall be Type S, SE, SEO, SEOO, SJ, SJE, SJEO, SJEOO, SJO, SJOO, SJT, SJTO, SJTOO, SO, SOO, ST, STO, or STOO, except for the wiring of chain-supported lighting fixtures and supply cords for portable lamps and other merchandise being displayed or exhibited.
Connection of stationary equipment to facilitate their frequent interchange;
Prevention of the transmission of noise or vibration;
Appliances where the fastening means and mechanical connections are designed to permit removal for maintenance and repair;
Data processing cables approved as a part of the data processing system;
Temporary wiring as permitted in paragraph (a)(2) of this section.