Remember that gas tanks were directly vented, for many years, and carbs, air cleaners, and some gas tanks had vent tubes that dripped. Horror stories of vehiclkes catching fire because someone tossed a cigarette butt are hard toi find, and most relate to puddled fuel from fuel system leaks. The Lower Exposive Limit (Lower Flammable Limit) of gasoline is 1.4%. That's a lot of drips in an area the size of a garage. The fire danger is minimal to non-existant. Worry because you don't like the fumes, worry because you don't like seeing drips, worry because the system is not protecting the atmoshpere as it is supposed to, but please don't worry because of the danger of fire. These vent tubes dump on the ground to allow condensed vapors to drop down and safely evaporate. It is doing what it is supposed to do. It just does it more like an old atmospheric vent instead of a modern emissions system as it is supposed to do.
