The Ikaros model Mk-II Man-Overboard Smoke Signal made by Hansson Pyrotech AB is a 15-minute smoke-signal device that is used on ring lifebuoys and is U.S. Coast Guard-approved.
The device is typically used aboard large ships and is installed on the bridge wing for quick deployment. When the ring buoy is removed from its bracket, an igniter mechanism is activated, producing the smoke. Once started, the ignition process cannot be stopped.
Recently, a seaman was inspecting a ring buoy on a ship in port and in the process began to move the buoy from its bracket. The igniter engaged. The seaman tried to return the ring to its bracket and force the igniter mechanism back into the signal. The result was a pressure buildup in the signal and a subsequent explosion that killed the seaman.
Hansson has now developed a new model, the Mk-III, which incorporates a pressure-relief valve to make the signal safer. The Coast Guard recommends replacing the MK-II with the MK-III or placing a placard nearby warning not to return the ring to its bracket if an accidental ignition has occurred.
