Coast Guard issues safety alert on ventilation closure devices

The following is a safety alert issued by the U.S. Coast Guard:

This Safety Alert addresses the importance of ensuring proper operation and adequacy of ventilation closure devices for spaces protected by fixed gas fire extinguishing systems on small passenger vessels. Properly operating ventilation closures ensure the effectiveness of the vessel firefighting systems and minimize the spread of fire to other areas of the vessel.

Recent vessel casualty investigations conducted by the U.S. Coast Guard and the National Transportation Safety Board (NTSB) into fires aboard small passenger vessels have raised awareness for the need to properly inspect and test ventilation closures for spaces protected by fixed gas fire extinguishing systems.

Federal Regulations require provisions for closing all supply duct cowls or scoops and exhaust duct discharge openings in spaces protected by fixed gas extinguishing systems. All closure devices must be readily available and mounted in the vicinity of the vent. As part of each annual inspection, attending marine inspectors should ensure the adequacy and serviceability of these closure devices in accordance with the CG 840 inspection guide. While observing fire drills in spaces covered by fixed gas systems, marine inspectors should ensure the vessel crews are familiar with these devices and ensure they are utilized properly during the conduct of the drill.

Small passenger vessels built on or after March 11, 1996 and small passenger vessels constructed of wood or fiber reinforced plastic (FRP) must have approved fixed fire extinguishing systems in certain machinery, fuel tank, and storage spaces which are described in 46 CFR 181.400 and 46 CFR 118.400. Vessels of other than wood or FRP construction built prior to March 11, 1996 must have a fixed system in machinery and fuel tank spaces using gasoline or other fuels having a flash point of 110° F or lower, paint and oil rooms, and cargo spaces which are inaccessible during a voyage and used for combustible cargo.

The U.S. Coast Guard strongly recommends that owners and operators, as well as marine inspectors, ensure the adequacy and test the operation of all ventilation closures for spaces protected by a fixed fire extinguishing system including both manual and automatic devices. Automatic closures should be tested and serviced by a qualified servicing facility in conjunction with the servicing of the fixed fire extinguishing system.

The regulations governing ventilation closures for spaces protected by a fixed gas fire extinguishing systems are contained 46 CFR Parts 182.465(h) and 119.465(h). These regulations are available through the U.S. Government Printing Office (GPO) and may be downloaded without cost from the GPO’s internet website A fixed gas fire extinguishing system installed but not required by regulation must still function properly including the operation of ventilation closure devices.

This safety alert is provided for informational purposes only and does not relieve any domestic or international safety, operational or material requirement. Developed by the Office of Vessel Activities, Domestic Compliance Division (CG-5431), United States Coast Guard Headquarters, Washington, DC. Questions should be directed to Lieutenant Commander David Webb at (202) 372-1216 or

By Professional Mariner Staff