Might be a rig to capture oxygen and refill all the empties. My dad used the machine up close or something like it to feed his nose mounted oxygen rig. And the 3 larger tanks looked similar to his liquid oxygen tanks… needs no electricity, although the top looked very different . Have no idea what the deal is with the propane tank. I see a generator and 3 gasoline tanks as well.. not such a safe idea to ave fuel and oxygen Cole together like that..the right mix It will turn a spark into a bomb and blow the building apart.