Gilldiver
Contributor
You can't really use the air in a BC as a rebreather when ascending, especially in the last 30 feet or so, as the air is expanding and has to be vented by the over pressure valves of the BC. If the valves are venting, you cannot force air into it with your lungs. Just try to blow air into any BC when it is so filled that the valves are venting.
As for the speed of a real emergency accent, it will be way more then 30 or 60 feet per minute. It will be at least 100 and more likely 200+ feet per minute, blowing all the way. The maximum speed is about 350 feet per minute as found in submarine escape testing back in the 50's when they did 330 feet in 56 seconds. But escape suits have a large air bubble per their design to pull you to the surface as fast as possible.
As for the speed of a real emergency accent, it will be way more then 30 or 60 feet per minute. It will be at least 100 and more likely 200+ feet per minute, blowing all the way. The maximum speed is about 350 feet per minute as found in submarine escape testing back in the 50's when they did 330 feet in 56 seconds. But escape suits have a large air bubble per their design to pull you to the surface as fast as possible.
