See, be seen, be heard

The International Maritime Organisation (IMO) 1972 International Regulations for Preventing Collisions at Sea, commonly referred to as the ColRegs, lays down specific requirements for sound-signalling equipment for use on boats and ships.

Kahlenberg air horns are certificated by the British MCA, the US Coast Guard and ABS among others as complying with the ColRegs.

It is a fact that the horns fitted to many craft are non-compliant. In addition to the obvious safety questions that this poses, owners and skippers also might be faced by additional issues such as whether they have invalidated their insurance cover.

ColRegs guidance note

To assist you du Pré Marine has prepared a guidance note on the sound signal requirements of the 1972 International Regulations for Preventing Collisions at Sea.

IMO Requirements for sound signalling is a 168kb pdf file.