Code Change Summary: A new informational note addresses the painting of data cables.

NEC Section 725.24 requires Class 1, Class 2, and Class 3 cables to be installed in a neat and workmanlike manner. This section also requires data cables to be supported by the building structure using straps, staples, hangers, cable ties, or similar fittings in a way that the cable will not be damaged by normal building use.

In the 2020 NEC^®, an informational note was added to remind the code reader that even painting the data cables is a mistake.

Often, after all wiring, HVAC systems, plumbing and other building elements have been installed, the painter will come through and spray paint everything above the ceiling one solid color (see image). Unfortunately, when data cables are painted, there is no way to tell if the cable insulation will still perform as intended.

Some data cables have a cable jacket that is suitable to be used in a plenum and have low smoke and heat release properties. Other data cables are riser rated which means they have been evaluated to be used where vertically penetrating one of more floor levels in a building. Applying paint over the cables was not the intent when the cables were evaluated and listed by a Nationally Recognized Testing Laboratory such as Underwriters Laboratories (UL).

Below is a preview of the NEC^®. See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2020 NEC^® edition of NFPA 70.