Section 181.450 - Interconnected detection and alarm system(a) An interconnected detection and alarm system must: (1) Consist of multiple-station smoke detectors listed by an NRTL, or independent laboratory accepted by the Commandant according to 46 CFR subpart 159.010, as meeting UL 217 (incorporated by reference, see 46 CFR 175.600 );(2) Be installed such that the actuation of alarm in one area results in both audible and visual alarms in all areas required by 46 CFR 181.405(c) or 118.400(d) to be protected by the interconnected detection and alarm system;(3) Contain an independent power source; and(b) A fire detection and alarm system of an approved type installed in accordance with 46 CFR part 76 would satisfy the requirements of this section.USCG-2021-0306, 86 FR 73172 , Dec. 27, 2021