01/02/25 Dry yes dry dive. Otherwise known as a pot dive

dry-activities -> events

Move to Dry Activities/Events on 1/2/25

Finally, a dive where no one got wet! Ok a slight cheat in as much as we were not even in the water.
 
Not in the water but still a great dive! Confused yet?
Well, this particular weekend we did a ‘dry dive’ in a recompression chamber.
An experience that you should try if the opportunity presents.
 
A summary of the day.
 
First the pre-checks. Are all participants dive qualified? (i.e. a proven understanding of pressure changes and its effects on the body). Are all likely to survive the trip? (current medical with no adverse medications). All of us passed so we were off to the Midlands Recompression Chamber in Rugby.
 
On arrival we were greeted by a team of 3 staff, presented with a souvenir mug that even came with unlimited tea & coffee refills.
 
Once all present we sat down for an introduction to the facility; of course, the now obligatory dos and don’ts to satisfy the HSE etc.
But where this talk excelled was a great insight into symptoms, evidence and actions surrounding a decompression incident.
The treatment programs were explained as was the likely sequence of events, where you’re likely to be treated and how to access such.
All very informative (and more tea/coffee).
 
A change of clothes next, into hospital scrubs. Strange? And some seemed to enjoy this part the most! The reasoning is to ensure no sparks are created from clothing or ancillary items. A pressurised chamber is oxygen rich and as such a potential fire hazard.
 
Nearly ready to go now, so getting nervous. Am I going to be the one to abort for everyone because I cannot equalise the pressure in my ears? Chamber pre-chat and worry abated. In such an event there is an air lock whereby exit is possible. Ok, really ready now.
 
We entered the chamber in 2 groups of 6 of which I was in group 1. We sat on comfy aircraft styled seats whilst the staff member who dived with us gave his colleagues the ok and we started to compress.
Three slow metres, then a pause to check all good with everyone. Then quickening up the pace a little and down to the target of 40M equivalent. The air gets thick and heavy, as well as very warm (feel your diving cylinder when its being filled with compressed air).
Now who will speak first? Wez! Or at least I think it was Wez, could have been Pinky (does anyone remember Pinky & Perky).
Shall I laugh at him? Best to try myself first, oh no Perky has joined us. For the none diving physics initiated, the change in pressure affects the voice.
Another effect of the raised partial pressures is Nitrogen Narcosis (a little like intoxication). We were given some simple puzzles to complete, and we actually did very well. Maybe we are used to Nitrogen effects from our diving, or maybe just used to be intoxicated.
 
Ok we don’t want to be ascending for ever, so it was time to start letting the pressure out. Very loud as the gas vents from the chamber but luckily, we were issued with ear defenders. The starkest change was the temperature going from very warm to very cold and the chamber filling with mist (again put your hand on your diving cylinder valve whilst air is being taken, and you will feel the cold).
As our equivalent depth decreased to a predetermined level (18M I think it was), we switched to breathing pure oxygen through individual masks. Excessive caution for our depth & time but better safe than sorry.
 
Up to the surface and out of the chamber to let the second group enter. We stopped in sight of the attendant for a period of monitoring then changed back out of the scrubs.
 
As with any dive be it wet or dry, the mandatory debrief was in the pub.
Everyone splits and heads home after a good day.
As more of our current trainees qualify, hopefully we will visit again.
 
Expedition leader
Gavin