Under Article 400.8 Uses Not Permitted (3) When run through doorways, windows or similar openings; how strict are we talking? I've been requested to power up a piece of equipment on the other side of a doorway. There is no power in the area where the equipment is to be used. The equipment is temporary in its use, about (1) week, then it leaves my site for good. Can a cord be run through the doorway, if secured open to protect the cord?