Section 28.155 - Excess fire detection and protection equipment(a) Use of non-approved fire detection systems may be acceptable as excess equipment provided that-(1) Components are listed and labeled by an independent, nationally recognized testing laboratory (NRTL) as set forth in 29 CFR 1910.7 , and are designed, installed, tested, and maintained in accordance with an appropriate industry standard and the manufacturer's specific guidance; and(2) The system and units remain functional as intended.(b) The regulations in this section have preemptive effect over State or local regulation within the same field.USCG-2012-0196, 81 FR 48247 , July 22, 2016