I have read there is a difference between marine aerial flares and wilderness aerial flares. Marine flares will burn longer, as there is no chance (?) for them to ignite material after hitting the water. Wilderness flares will burn for a shorter period of time so that there will be no chance (?) of them igniting a fire after hitting the ground, as they should be burned out by then.
To the uninformed, an aerial flare is an aerial flare.
There is a reason to use/carry the proper signal equipment and understand the dangers.