Incident Report

2013-05-04In a new underwater cave (unreported as yet in the CDG Newsletter) I was returning through a restriction 70 m from base. This takes the form of a tube which is small but passable which also has a longitudinal slot in the floor. This slot accomodates a tank allowing the restriction to be passed through without removing any tanks (just!). Before the dive I found Id packed thewrong regulator for the tank on that side so I undid the tank band and rotated the tank through 180 degrees (which allowed the hoses on thewrong regulator to be aligned favourably but also altered the position of the 1st stage relative to normal). The tank jammed itself in the slot in the floor of the restriction and it didnt seem to want to become free again. After a few goes I decided to detach the tank from me temporarily just to free it from the crack - but as I was right in the restriction I wasnt able to move far enough away to unclip the tank band from the D ring on my harness. I played with it idly for a while at one point contemplating the possibility of cutting the loop connecting the krab to the tank band. However I eventually managed to free the tank in the end. It was never a crisis but it occurred to me whilst it was happening that some people use steel links between tank bands and their harness D rings which of course doesnt leave the option of cutting if all else fails. This in retrospect is probably not a good system.1. If familiar with a restriction in an underwater cave and an unexpected alteration to equipment has to be made before diving dont assume the manouevres through the restriction will go as smoothly as normal. 2. Always have some sort of cuttable loop between the tanks and the krabs which clip them to harness D rings because a tank might jam itself in a crevice in a situation where its impossible to unclip yourself from the tank.