Last week while visiting Ogof Fechan I found a pair of 4ltr ex BA cylinders with din valves stashed just beyond the sump1 bypass. One was in an old Dudley caving bag, the other loose and they appeared to have been there for some time.
Despite efforts to locate the owner I've so far drawn a blank. The cylinders displayed a certain level of surface corrosion and I suspect they wouldn't pass test, but you never know. I'd be inclined to leave or certainly empty first before considering removal.
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