No air left. Unable to do controlled ascent!
- Thread starter scubette
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
- Messages
- 6,921
- Reaction score
- 25
- # of dives
- I just don't log dives
alcal
Registered
Hi
Read all the posts and hopefully learned a lot thankyou guys and gals.
In my dive Centre in the UK we are dry suit trained and eventually encouraged to learn to use the suit for underwater bouyancy and only use the BCD for pre and post dive surface bouyancy,although all our instructers and DM`s will also say use whichever works best for you as an individual but just avoid `pinch` in the suit if nothing else.
We have been trained for full kit removal and replacemnt also weight removal and replacement,we are constantly reminded and evaluated on air consumption and gauge checks and ALWAYS do buddy checks.We also ascend as buddies keeping level , close and facing each other using eye contact, I guess im just saying i feel well trained from what ive read on some of these threads.
I took OW in August and AOW in October and have four specialities including PPB Deep Night and Digi Photography,i consider myself a new diver of 49 dives including UK sea and Red sea in my log.
Something didnt sound right to me about the instructor critisising the decision to head for his buddy rather than the surface,i can only go by my Padi Training but i think he`s wrong,of course circumstances may change the priority in which you decide what action to take but everything else being equal as it does sound i would refer to page 158 in the Open Water manual LOW ON AIR OUT OF AIR SITUATIONS
(Excluding 1/ Normal ascent on low air)
2/Your are advised to Ascend using an alternate air source first .
3/A CESA comes next but even then is based on you being less than 20 to 30 feet down(not 47/43).
You shouldnt have tried to CESA at that depth ,it should have been alternate air then 4/buddy breath before even thinking about trying to reach the surface or am i missing something here???
Of course this is a discussion after the event and you were the diver actually in this situation so .......glad you kept your head and survived it but it sounds as if your training (or your interpretation of it) possibly made you head for the wrong solution first?? .
Best wishes
Alan
Read all the posts and hopefully learned a lot thankyou guys and gals.
In my dive Centre in the UK we are dry suit trained and eventually encouraged to learn to use the suit for underwater bouyancy and only use the BCD for pre and post dive surface bouyancy,although all our instructers and DM`s will also say use whichever works best for you as an individual but just avoid `pinch` in the suit if nothing else.
We have been trained for full kit removal and replacemnt also weight removal and replacement,we are constantly reminded and evaluated on air consumption and gauge checks and ALWAYS do buddy checks.We also ascend as buddies keeping level , close and facing each other using eye contact, I guess im just saying i feel well trained from what ive read on some of these threads.
I took OW in August and AOW in October and have four specialities including PPB Deep Night and Digi Photography,i consider myself a new diver of 49 dives including UK sea and Red sea in my log.
Something didnt sound right to me about the instructor critisising the decision to head for his buddy rather than the surface,i can only go by my Padi Training but i think he`s wrong,of course circumstances may change the priority in which you decide what action to take but everything else being equal as it does sound i would refer to page 158 in the Open Water manual LOW ON AIR OUT OF AIR SITUATIONS
(Excluding 1/ Normal ascent on low air)
2/Your are advised to Ascend using an alternate air source first .
3/A CESA comes next but even then is based on you being less than 20 to 30 feet down(not 47/43).
You shouldnt have tried to CESA at that depth ,it should have been alternate air then 4/buddy breath before even thinking about trying to reach the surface or am i missing something here???
Of course this is a discussion after the event and you were the diver actually in this situation so .......glad you kept your head and survived it but it sounds as if your training (or your interpretation of it) possibly made you head for the wrong solution first?? .
Best wishes
Alan
Bogie
Contributor
1. It does not make sense that you had 500 psi and ran out of air. Perhaps you looked at the guage incorrectly. Perhaps your SPG is faulty. I would not dive with the SPG until you have it checked and serviced. Your life depends on it. Unless you were breathing like a steam engine you should have been OK. When your learning new tasks (multi-tasking) you always burn more air. For your next dives I would surface at 1000 psi until you find the solution.
2. Drysuit and Bouyancy. Go to the DUI web site www.dui-online.com/pdf/drysuitmanual.pdf and read the manual. It says if the air bubble gets bigger than mid elbow on raised right arm use you bcd for bouyancy. If the air bubble in your drysuit is bigger it becomes dangerous.
3. You did great as circumstances presented themselves. You did not panic, remained thoughtful, and found the solution that worked and the resulted in everyone surfacing safely.
I would find out what was the cause of this situation so it never happens again. Some things I do are: while ascending I look at my SPG to monitor my assent rate, which shows my psi, I test my breathing consumption rate ( (for a short test time)I will breath faster or slower and look at my psi) this gives me a better idea of psi consumption rate, it is amazing how much air you can burn when you are excited, psi consumption much higher at deeper depth, monitor guages closely and continuously, stay close to buddy on assent, carry a 6cu spare air. I do this mostly automatically so it is no big deal.
Note: In a drysuit air seems to dump slower which can put you in an unwanted assent. You can raise your shoulder and press the dump valve. It still may not come out as fast as you like. If you want to dump it even faster, get vertical this forces all the air in your suit to rise to your shoulders, raise your shoulder with the exhaust valve and hit the dump. I dive with my exhaust valve open. This of course is while your learning. After awhile you will just make slight adjustments, good bouyancy control, less energy, air will last longer, and safer diving. I love drysuit diving.
I commend you on your excellent choices, no panic, thoughtful, and excellent results.
2. Drysuit and Bouyancy. Go to the DUI web site www.dui-online.com/pdf/drysuitmanual.pdf and read the manual. It says if the air bubble gets bigger than mid elbow on raised right arm use you bcd for bouyancy. If the air bubble in your drysuit is bigger it becomes dangerous.
3. You did great as circumstances presented themselves. You did not panic, remained thoughtful, and found the solution that worked and the resulted in everyone surfacing safely.
I would find out what was the cause of this situation so it never happens again. Some things I do are: while ascending I look at my SPG to monitor my assent rate, which shows my psi, I test my breathing consumption rate ( (for a short test time)I will breath faster or slower and look at my psi) this gives me a better idea of psi consumption rate, it is amazing how much air you can burn when you are excited, psi consumption much higher at deeper depth, monitor guages closely and continuously, stay close to buddy on assent, carry a 6cu spare air. I do this mostly automatically so it is no big deal.
Note: In a drysuit air seems to dump slower which can put you in an unwanted assent. You can raise your shoulder and press the dump valve. It still may not come out as fast as you like. If you want to dump it even faster, get vertical this forces all the air in your suit to rise to your shoulders, raise your shoulder with the exhaust valve and hit the dump. I dive with my exhaust valve open. This of course is while your learning. After awhile you will just make slight adjustments, good bouyancy control, less energy, air will last longer, and safer diving. I love drysuit diving.
I commend you on your excellent choices, no panic, thoughtful, and excellent results.
underwaterfrank
Registered
Hi,
happy to hear you made a safe exit from that nasty situation. You don't have time to think in such situations so you got the air from your buddy. Excellent.
Going to the surface with "empty" lungs from 47 feet is a long trip and you think you would have struggled to make it, but also remember this:
- you could have been solo diving or too far from your buddy, in which case there was only one way out, so it's important to know what your alternative option was
- as soon as you swim upwards the remaining air in your suit and BC will expand and you would ascend faster and faster without needing to exert effort (something you normally want to avoid of course). You don't need to use much effort or consume a lot of oxygen to make it to the surface from that depth. Rushing it makes it worse as you produce more CO2 which gives you the signal you need to inhale, trying to stay calm is the trick. (easy to say, hard to do)
- when doing a CESA, as long as you keep your head tilted back to keep your larynx open, the expanded air will escape. In the "old" days doing these ascents without mouthpiece in the mouth from depths of 45 to 90 feet was actually part of standard advanced certificate training in some organisations such as CMAS. I think it has now been abandoned as it's too dangerous, but I've tried it a couple of times and it works fine.
In your case you did not have much air in your lungs, so exhaling it on purpose from the start would have probably meant you'd be gasping for air way before you would have reached the surface.
- the trip to the surface from that depth probably takes less than 30 seconds (unless the diver has problems controlling buoyancy and is too heavy at the start of the ascent), so even if you think you are going to drown, there is a good chance you will make it all the way without even gasping for air.
All I'm trying to say is, the option of going to the surface, assuming you didn't have any deco stop commitments, was not necessarily the worst.
If you hadn't found your buddy immediately, or if he had panicked and responded incorrectly, you may be worse off.
Always consider diving in such a way that you can be totally self-sufficient if something like this happens. For example, carry a Spare Air, or dive to a plan that allows you to surface using only your own resources, at any time.
You will learn this over time. Always ask your instructors to explain the options, and practice all of them (if safe to do so, and under instructor supervision). there is always a "theoretical" best option, and a "real life" practical solution when things really go wrong. The two are not always one and the same.
happy to hear you made a safe exit from that nasty situation. You don't have time to think in such situations so you got the air from your buddy. Excellent.
Going to the surface with "empty" lungs from 47 feet is a long trip and you think you would have struggled to make it, but also remember this:
- you could have been solo diving or too far from your buddy, in which case there was only one way out, so it's important to know what your alternative option was
- as soon as you swim upwards the remaining air in your suit and BC will expand and you would ascend faster and faster without needing to exert effort (something you normally want to avoid of course). You don't need to use much effort or consume a lot of oxygen to make it to the surface from that depth. Rushing it makes it worse as you produce more CO2 which gives you the signal you need to inhale, trying to stay calm is the trick. (easy to say, hard to do)
- when doing a CESA, as long as you keep your head tilted back to keep your larynx open, the expanded air will escape. In the "old" days doing these ascents without mouthpiece in the mouth from depths of 45 to 90 feet was actually part of standard advanced certificate training in some organisations such as CMAS. I think it has now been abandoned as it's too dangerous, but I've tried it a couple of times and it works fine.
In your case you did not have much air in your lungs, so exhaling it on purpose from the start would have probably meant you'd be gasping for air way before you would have reached the surface.
- the trip to the surface from that depth probably takes less than 30 seconds (unless the diver has problems controlling buoyancy and is too heavy at the start of the ascent), so even if you think you are going to drown, there is a good chance you will make it all the way without even gasping for air.
All I'm trying to say is, the option of going to the surface, assuming you didn't have any deco stop commitments, was not necessarily the worst.
If you hadn't found your buddy immediately, or if he had panicked and responded incorrectly, you may be worse off.
Always consider diving in such a way that you can be totally self-sufficient if something like this happens. For example, carry a Spare Air, or dive to a plan that allows you to surface using only your own resources, at any time.
You will learn this over time. Always ask your instructors to explain the options, and practice all of them (if safe to do so, and under instructor supervision). there is always a "theoretical" best option, and a "real life" practical solution when things really go wrong. The two are not always one and the same.
JohnB47
Contributor
Scubette,
I am not sure which choice I would have made in that situation, but the one you made was definitely not wrong. You didn't panic, you used your head, and you completed the dive safely. I would be happy to have you for a buddy!
...John
I am not sure which choice I would have made in that situation, but the one you made was definitely not wrong. You didn't panic, you used your head, and you completed the dive safely. I would be happy to have you for a buddy!
...John
I would like to add, many Instructors (not all) while teaching the Drysuit course will have you use your drysuit only to control your buoyancy and not touch your BC simply to get used to the suit first. Drysuit divers as they get more experienced with their suits will adjust their buoyancy using their drysuit and BC. You made the right choice as far as I can see from the details you've given. We are faced with making decisions such as this all the time. I have had to make some myself. This weekend I made one as well. You wonder, did I make the right move? You're alive and breathing. Glad you made it out ok.
Similar threads
