46 CFR § 182.480 - Flammable vapor detection systems.
---
identifier: "/us/cfr/t46/s182.480"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 182.480 - Flammable vapor detection systems."
title_number: 46
title_name: "Shipping"
section_number: "182.480"
section_name: "Flammable vapor detection systems."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "T"
subchapter_name: "SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS)"
part_number: "182"
part_name: "MACHINERY INSTALLATION"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "46 U.S.C. 3306; E.O. 12234, 45 FR 58801, 3 CFR, 1980 Comp., p. 277; DHS Delegation No. 00170.1, Revision No. 01.4."
regulatory_source: "CGD 85-080, 61 FR 986, Jan. 10, 1996, unless otherwise noted."
cfr_part: "182"
---
# 182.480 Flammable vapor detection systems.
(a) A flammable vapor detection system required by § 182.410(c) must meet UL 1110 (incorporated by reference; see 46 CFR 175.600) or be approved by an independent laboratory.
(b) Procedures for checking the proper operation of a flammable vapor detection system must be posted at the primary operating station. The system must be self-monitoring and include a ground fault indication alarm.
(c) A flammable vapor detection system must be operational for 30 seconds prior to engine startup and continue sensing the entire time the engine is running.
(d) A flammable vapor detection system must provide a visual and audible alarm at the operating station.
(e) A sensor must be located above the expected bilge water level in the following locations:
(1) The lowest part of a machinery space;
(2) The lowest part of a space containing a fuel tank when separate from the machinery space; and
(3) Any other location when required by the cognizant OCMI.
(f) A flammable vapor detection system must be installed so as to permit calibration in a vapor free atmosphere.
(g) Electrical connections, wiring, and components for a flammable vapor detection system must comply with part 183 of this chapter.
(h) An operation and maintenance manual for the flammable vapor detection system must be kept onboard.
[CGD 85-080, 61 FR 986, Jan. 10, 1996, as amended by USCG-2003-16630, 73 FR 65209, Oct. 31, 2008]