LIFE BUOY WEIGHT OVER 4KGS, MED APPROVED 330160

Use this code for the buoys that operate a quick-release arrangement for smoke signals and lights. The LSA Code as adopted only said such a buoy must have “a mass sufficient to operate the quick release arrangement”. MSC.207(81), in force from 1 July 2010, replaced this with “of not less than 4 kg”. Every other lifebuoy needs only 2.5 kg, which is IMPA 330159.^[1][2]

The same amendment requires the lifebuoy smoke signal to have a quick-release arrangement that releases and starts the signal and its light when connected to a lifebuoy of not more than 4 kg. So the 4 kg figure works both ways: the buoy must weigh at least 4 kg to work the release, and the signal’s release must work with a buoy of not more than 4 kg. Match the buoy to the marker maker’s instructions.^[2]

Count how many you need. US rules call for at least two lifebuoys with self-activating smoke signals, stowed so they can be released from the navigating bridge, and those buoys also carry lights. Order the smoke-and-light markers on their own line from the pyrotechnics groups, and give the holder model if it stays. Ask for the ship’s name and port of registry in block capitals.^[3]

Every SOLAS lifebuoy must have an outer diameter of not more than 800 mm and an inner diameter of not less than 400 mm, support at least 14.5 kg of iron in fresh water for 24 h, and survive a drop from its stowage height or 30 m, whichever is greater. These apply to the 4 kg class as to the 2.5 kg class.^[1]

Lifebuoys are item MED/1.1 under the Marine Equipment Directive. Implementing Regulation (EU) 2025/1533, in force from 23 September 2025, updated the item’s standards. The maker shows conformity with the wheel mark and a Declaration of Conformity.^[4]