Do you really have to exhale while ascending?

[redrover]

As you breathe in and out your buoyancy will change by several pounds. Full lungs are much more buoyant than near empty lungs.

My preference when using 3mm or 5mm wetsuits is to be neutrally buoyant --
at 15' depth
near empty tank
no air in BCD
lungs near full -- i.e inhaled close to the my normal maximum inhale

As I ascend towards the surface my wetsuit will expand and add buoyancy. I compensate for this additional buoyancy by not fully inhaling. In other words, I am willing to exhale and then do shallow breathing for the short period it takes to do a slow, controlled ascent over the last few feet to the surface. In reality I still will do fairly large breathing cycles, but I just spend more time with my lungs near empty and relatively little time with my lungs nearly full.

I'm willing to do this in order to reduce the amount of lead I carry by 3 or 4 pounds. This reduction in lead means that I have that much less air in my BCD throughout the dive, making buoyancy control easier.

Charlie Allen

Ahhh.
Could have never explained it that well, mahalo.

 

[justkaydub]

I have to ask why the original question was asked????

NJMike you quoted an article detailing an injury because they held their breath in the last 6 ft!!!!


Why ask the obvious?? It suggeste to me that you dont' believe your instructor, your certifying agency and the article written.

I have been on this board (and many others) and I am constantly amazed at newly certified divers and dive students questioning safety issues.

I appreciate this might be a harsh response, but cripes people think before you post!

While I believe the answer is very easy, (Just never hold your breath). I'm still glad he asked it because his question spawned one of the most entertaining threads I have read on here, and the thread got into so many other avenues including bouyancy issues at different depth and with 3000 vs 500 psi etc. It was fun to read, glad he wasn't affraid to ask for fear of being told to think before he posts.

 

[Blackwood]

Just never hold your breath

... unless you have to.

 

[jupitermermaid]

As you breathe in and out your buoyancy will change by several pounds. Full lungs are much more buoyant than near empty lungs.

My preference when using 3mm or 5mm wetsuits is to be neutrally buoyant --
at 15' depth
near empty tank
no air in BCD
lungs near full -- i.e inhaled close to the my normal maximum inhale

As I ascend towards the surface my wetsuit will expand and add buoyancy. I compensate for this additional buoyancy by not fully inhaling. In other words, I am willing to exhale and then do shallow breathing for the short period it takes to do a slow, controlled ascent over the last few feet to the surface. In reality I still will do fairly large breathing cycles, but I just spend more time with my lungs near empty and relatively little time with my lungs nearly full.

I'm willing to do this in order to reduce the amount of lead I carry by 3 or 4 pounds. This reduction in lead means that I have that much less air in my BCD throughout the dive, making buoyancy control easier.

Charlie Allen

You wrote this perfectly. It's kinda what I was trying to say in my response, but you were much more clear and precise.