Venting valve for inflatable dock seals

In an inflatable dock seal for positioning on a wall around an opening therein and having means for inflating the same, a quick venting valve in communication with said inflatable dock seal and comprising a flexible tubular member extending outwardly therefrom, means normally supporting said flexible tubular member inwardly of the ends thereof so that a portion of the flexible tubular member is held in position outwardly of the inflatable dock seal and another portion of the flexible tubular member is unsupported and normally folded inwardly against the supported portion so as to form a closure in said flexible tubular member, said flexible tubular member arranged to temporarily unfold and open responsive to increased air pressure in said inflatable dock seal as occasioned by a truck or a trailer striking the inflated dock seal.