Dive computer sensitivity

[LanceRiley]

whenever I go up... I don't kick up. I just use my lungs to rise slowly. readjusting bouyancy as I reach the surface.. no way am i kicking to get up. a series of inhale inhale and exhale... with get me up.

 

[redacted]

whenever I go up... I don't kick up. I just use my lungs to rise slowly. readjusting bouyancy as I reach the surface.. no way am i kicking to get up. a series of inhale inhale and exhale... with get me up.

Using your lungs to power the elevator needs to be done very slowly and carefully to avoid a lung over expansion injury. For faster ascent rates, still withing recommended limits, using your legs may be a safer option.

 

[KC2k12]

I am a newer diver with a Oceanic VT3 and I've had the same problem on almost every dive.

How big is the risk of injury of instantaneous ascent rates exceeding 'safe' limits? Obviously, ascending at a high average rate is a bad idea, but what about sudden ascents of 5 feet or so?

 

[Bubbletrubble]

I am a newer diver with a Oceanic VT3 and I've had the same problem on almost every dive.

How big is the risk of injury of instantaneous ascent rates exceeding 'safe' limits?

@KC2k12: It's difficult to quantify the risk. I think the most correct thing to say is: "It increases." And leave it at that.

Obviously, ascending at a high average rate is a bad idea, but what about sudden ascents of 5 feet or so?

Several factors beside the absolute depth change determine risk of injury, e.g., current volume of gas in the lungs, any pre-existing medical condition that creates weaknesses in the lung tissue, whether the glottis is open/closed, relative pressure change (5 ft. depth change is more serious closer to the surface), etc.

As a newer diver struggling with buoyancy control, the best thing to do is what you were taught in basic OW class: continuously breathe/never hold your breath.

Strive to be neutrally buoyant most of the time. Practice your hovering skills...a lot. During ascents and descents, pick out intermediate depth points and control your movement in the water column so that you can stop at those points. For example, upon initial descent, see whether you can stop at 5 ft., 10 ft., 15 ft., 20 ft., 25 ft., 30 ft., etc. Once you feel a little more comfortable, try to do this in a horizontal position without kicking. It takes lots of little taps on the power inflater to do this.

Living in the San Diego area, La Jolla Shores is an ideal dive site for seeing UW critters, practicing hovering skills, and learning how to do controlled descents/ascents.