Deefstes
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This is probably no big deal but I'm starting the thread to find out
We've been taught that safety stops should be made at 3m for 1 minute. This is according to the Buhlmann tables. That said, I know many divers who's been trained to do safety stops at 5m for 3 minutes. At first I struggled a bit to remain neutrally buoyant at 3m and my instructor told me not to worry and rather do the stop at 5m for 3 minutes then. Now that I have my buoyancy better under control I actually like the 3m stops better. Do you guys have any opinions on this one way or the other?
My more important question is this though. Is there a compelling reason why you should be in horizontal trim during your safety stop? I remember reading once that if you're in an upright position there is a pressure differential across your lungs from top to bottom which has an adverse effect on your off-gassing. WHAT?!?!? Could that really be? I mean my lungs are probably about 30cm from top to bottom. That's a 0.03 Bar pressure differential on my lungs if I'm in an upright position. Moreover, I'm not convinced my lungs actually do experience that pressure differential as it is a single enclosed space. By analogy, if I take an inflated balloon under water, will the pressure inside that balloon vary from top to bottom or will it have a single internal pressure that is the average of the balloons depth in the water column?
But I'm getting in to deep. What I really want to know is, what are the pros and cons of being in an upright / horizontal position while doing your safety stop. Personally, and I know this is probably wrong but it works well for me, I am in an upright position. I carry 4kg of weight which makes me slightly negatively buoyant. On my safety stop I stay in an upright position and can then either slightly inflate my BC to stay neutrally buoyant or I can purge all air from my BC and just give a gentle frog kick downwards every 10 seconds or so.
Now accepting your inputs
We've been taught that safety stops should be made at 3m for 1 minute. This is according to the Buhlmann tables. That said, I know many divers who's been trained to do safety stops at 5m for 3 minutes. At first I struggled a bit to remain neutrally buoyant at 3m and my instructor told me not to worry and rather do the stop at 5m for 3 minutes then. Now that I have my buoyancy better under control I actually like the 3m stops better. Do you guys have any opinions on this one way or the other?
My more important question is this though. Is there a compelling reason why you should be in horizontal trim during your safety stop? I remember reading once that if you're in an upright position there is a pressure differential across your lungs from top to bottom which has an adverse effect on your off-gassing. WHAT?!?!? Could that really be? I mean my lungs are probably about 30cm from top to bottom. That's a 0.03 Bar pressure differential on my lungs if I'm in an upright position. Moreover, I'm not convinced my lungs actually do experience that pressure differential as it is a single enclosed space. By analogy, if I take an inflated balloon under water, will the pressure inside that balloon vary from top to bottom or will it have a single internal pressure that is the average of the balloons depth in the water column?
But I'm getting in to deep. What I really want to know is, what are the pros and cons of being in an upright / horizontal position while doing your safety stop. Personally, and I know this is probably wrong but it works well for me, I am in an upright position. I carry 4kg of weight which makes me slightly negatively buoyant. On my safety stop I stay in an upright position and can then either slightly inflate my BC to stay neutrally buoyant or I can purge all air from my BC and just give a gentle frog kick downwards every 10 seconds or so.
Now accepting your inputs