Wearing mask under the hood ended a CCR dive. A flooded mask ended this Rebreather dive
On my second dive, my mask flooded after jumping into the water. On the surface I cleared the mask. Continuing the dive, my mask flooded again at a depth 15 fsw (5 msw). I couldn’t tighten the straps on my mask because I was wearing a hood over the mask. By now my counter lungs were empty from clearing the flooded mask and I was gasping for air. I went to the surface and called for assistance (a line to pull me to the ladder). This ended my second dive.
In this case the diver felt his mask needed adjustment and he soon found himself out of breath so aborted the dive. Many, but not all, hoods can be pulled to the back of the head while underwater and then replaced after adjusting the mask. This can be complicated by thick gloves, or tanks/rebreathers that sit close to the back of the skull. A bailout valve, where the diver simply turns a switch to change to open circuit, could also have been another option, (if the diver’s rebreather had one), as could have adding gas to the breathing loop. No doubt in other circumstances even more options may have been available. On this particular day though, in these particular circumstances, the diver had an option to simply ascend and give-up the dive, and he took it. Sometimes, no matter how disappointing it may be, the safest option is to dive again another day.
~ Peter Buzzacott, MPH, PhD