Wiring Methods, Components, and
Equipment for General Use

Flexible cords and cables [1910.305(g)]

1910.305(g)(1)(iii)(C) Where run through doorways, windows, or similar openings;
1910.305(g)(1)(iii)(D) Where attached to building surfaces; or
1910.305(g)(1)(iii)(E) Where concealed behind
building walls, ceilings, or floors.