Q: What (if any) is the regulation on the governance of holiday lights in a healthcare occupancy?
A: Section 126.96.36.199 of the 2012 LSC only address combustible decorations, and does not address holiday lights. You didn’t say but it is presumed that the holiday lights are not combustible. The Life Safety Code does not address electrical decorations. However, the 2012 Life Safety Code does say under section 188.8.131.52 that any requirements that are essential for the safety of building occupants and that are not specifically provided for by this Code shall be determined by the authority having jurisdiction.
Your accreditation organization and likely your state agency that surveys on behalf of CMS, have standards that address electrical safety, or building safety. If you use holiday lights in an unsafe manner, then a surveyor can cite you for non-compliance with their general safety standards.
Often times these AHJs will expect you to have a policy on the safe use of holiday lights in your facility, that way they can hold you accountable to what your policy says. So if you have a policy on how you expect your staff to use holiday lights, then that will likely suffice.