Code Change Summary: New code language requires the proper fittings to be used when connecting a flexible cord or cable to a box for temporary installations.

For temporary installations, such as jobsite power, article 590 allows wiring methods and materials that would never pass inspection if installed in the same manner as a permanent wiring method.

For temporary jobsite power during construction, substandard wiring methods and practices are not only common, but they are allowed by the NEC^®. Nonmetallic sheathed cables are permitted to be strung throughout the building and even spliced openly above a suspended ceiling without a junction box. Because the cables are considered temporary, they are permitted to be used like this until the building is far enough along to get permanent power.

Often, one thing leads to another from jobsite to jobsite and before long, there are many temporary construction practices overlooked by the inspector simply because the wiring methods are only there for a short time. Unfortunately, it only takes a short time for a worker to get shocked when poor wiring methods are allowed to exist.

In the 2014 NEC^®, additional text was added in 590.4(I) to require the proper fittings to be used when connecting a flexible cord or cable to a junction or device box. All too often, a damaged flexible cord is cut and re-spliced into a box through a ½ in. or ¾ in. PVC male adapter with no cord strain relief. Other times a thick type SO cord is connected to a box using an NM cable connector simply because the NM connector is what happens to be in the electrician’s pouch at the time. It won’t be long until the cord will come loose from the NM cable connector and create a potential shock hazard. Before this code change, there was nothing in article 590 specifically prohibiting this practice.

Below is a preview of the NEC^®.  See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on the “free access” tab and select the applicable year of NFPA 70 (National Electrical code).