air supply stop for first stage
- Thread starter diver_lex
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gehadoski
Contributor
Hi there
May I ask you some questions?
1) Are you making maintenance to your equipments regularly?
2) Did you store your reg and forgot the dust cap open for a while?
3) At the begining of that dive did you hear something wrong with the tank??
May I ask you some questions?
1) Are you making maintenance to your equipments regularly?
2) Did you store your reg and forgot the dust cap open for a while?
3) At the begining of that dive did you hear something wrong with the tank??
What reg were you using?
What is its maintenence history?
What type of tank were you using?
When was the tank last inspected?
A total failure of a first stage to deliver air is very very rare but the above questions will help identify what may have went wrong.
What is its maintenence history?
What type of tank were you using?
When was the tank last inspected?
A total failure of a first stage to deliver air is very very rare but the above questions will help identify what may have went wrong.
diver_lex:No... no... I just try to understand than is conditioned requirement to have a spare air for solo diving.
Reason behind the practice of having a spare redundant air source?
I do not know of any failures of that nature, where the unit was good to depth and then failed allowing no air to pass but that is not the only reason behind a redundant air source...
I would configure a completely redundant system with suitable sized pony for the depth your intending to dive.
(I am assuming your not talking about the brand name spare air and talking about a redundant pony bottle in general...)
Jeff Lane
yak
Contributor
You also need to consider the somewhat more common failure of a second stage. If it happens at depth, say 120 f, and you are at or near your turning pressure for the dive, you *may* be able to sip air from a free-flowing reg and reach the surface, but you will not be able to make a safety stop, and risk a potential DCS hit.
diver_lex:
When your solo diving your only responsible for yourself, your making all the decisions and accepting all the risk so if you choose not to employ a redundant air source because the chance of failure is rare and you feel that is an acceptable risk it is your choice.
It is really going to depend on what your comfortable with you know...
My issue with making it a requirement... I would not want someone to accept an unneccessary risk unless they had a complete understanding of the risk involved and the potential outcomes in the event of a malfunction...
Jeff Lane
diver_lex:
A first stage failure is very rare, a second stage failure is less rare but then you should have an octo to use in the event that a happens. But runnung out of air due to poor air management or failure to monitor your air consumption is unfortunately all to common.
For solo diving you do not absolutetly need a redundant air supply - until you need one really really bad. And needing one really bad and not having it is what you avoid by having one.
Theoretically you could solo dive down to any depth to which you could readily make an emergency swimming ascent. But practically most people don't have the skills to safely and consistently make a free ascent from any significant depth. ESA's were taught and actually performed from depths of 30-40 feet in OW training 20 years ago and inspired a good deal of confidence in the diver. That is not the case today.
Additionally, getting hung up on the bottom for some reason (fish line etc) and delaying and ESA for even a minute or two can have fatal consequences if the reg chooses that particular time to stop delivering air.
With an ESA you also forfeit your ability to make a saftey stop and assume additonal risk of DCS.
To do an ESA from a depth of say 100 feet, you also need to be a very cool customer, be very efficient in the water and have the confidence that you can continue exhaling at the proper rate all the way to the surface. If you have not actually done it before under controlled conditions, the odds of doing it successfully in open water in an emergency situation with out panicking are very very small. And in the real world, you discover your reg has stopped delivering air after you have exhaled which changes the whole picture at depth.
When I started solo diving I also regularly freedove to 60-70 ft. and even with fairly good freediving skills I did not even consider solo diving without a pony bottle. It just is not worth the risk in my opinion.
So there are many reasons to have a redunant air source while solo diving and really no valid reasons not to have one.
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