This means that the link between the two cylinders is always open unless the isolator is closed. This preserves any remaining gas in the working cylinder.Īs you can see from the diagram (above), the manifold accesses air from the cylinder from below the cylinder valves. Most divers prefer to have the isolation valve, because it enables them to close the link between two cylinders in the event of a valve failure on either of the cylinder valves. Manifolds come with, or without, an isolation valve (the knob at the top). The use of long and short hose combinations, in conjunction with the bungee necklace is often called a 'Hogarthian' configuration.

From that position, it is easily and instantly deployable in an emergency. The long hose is kept streamlined by routing it around the body and behind the neck. The secondary regulator is typically secured on their neck, using a necklace made out of bungee cord. In this instance, they will donate their primary 'long' hose to an out-of-air diver and then transfer to breathe from their own secondary regulator. When using double cylinders, many divers prefer to use a long (5' or 7') hose as their primary and a short (22 - 24') hose as their secondary. These regulators are then used in a normal fashion, with one regulator (the 'primary') in the divers' mouth and a reserve regulator (the 'secondary') fulfilling the role of an alternate-air-source (AAS). Typically, these are DIN fitting regulators. Its purpose is to enable two tanks to work as one 'virtual' tank - delivering the full contents of both tanks to either regulator.ĭivers attach a regulator to both tank valves. (20' log chain with hooks and 40' of wirerope with loops on the end) Never saw so many pheasants in my life they were surrounding where the hay bales had been dropped by helicopter for the stranded cattle.The manifold is the 'bar' that joins the two cylinders (see below). IIRC I did have to use a come-a-long and pull it back on the road 3 times.

My 1968 ford ex-phone company van with tiny motor but good clearance made it out with food, water and propane. There was a massive snow storm and my boss asked me to go rescue two mudloggers who had opened both tanks at the same time and then ran completely out and were marooned as they had ridden out in their new Corvette and the ice on the roads was higher than its ground clearance. We were supposed to use one till it was empty and then switch to the other and get the first refilled. I used to work in a Mud Logging trailer with propane heat and two tanks. The problem being that at sometime both will be empty. Also the tank with less propane will chill down faster as it has less to chill and that will slow down evaporation too.

2 etank manifold