The USCG just released this advisory bulletin on Visual Distress Signals and old flares. Some information is specific to District 9--Great Lakes, the rest of the information is general to the US.
MUCH better than a handheld pyrotechnic flare.However, for location purposes the electric signaling devices are far superior to and safer than handheld flares. There is no slag dripping off the flare and the signaling device runs for hours, not minutes.
That slag is insane. I wonder how many people have any idea hot knarly that stuff is. I lit one off one day at work just to see how it works. I put it on the parking lot and it burned a 3" long x 2" deep hole in the tar pavement. I got rid of them all off my boat the very next day. I still have smoke though. Not sure if those also produce that molten slag but dont know of another option. Also grabbed a 25mm flare gun and flares to make up for the road flares.For general alert purposes the electric signaling devices are not as effective as a SOLAS flare. However, for location purposes the electric signaling devices are far superior to and safer than handheld flares. There is no slag dripping off the flare and the signaling device runs for hours, not minutes.