Breathing rate, air integrated computers and DCI correlation

[boulderjohn]

It uses time & temp.

Temperature of what? The water?

If so, then it would have adjusted for cold when I was sweating in my dry suit with too heavy underwear in Puget Sound and not adjusted for cold when I was shivering in Hawai'i in too little wet suit. In other words, it would have done the opposite of what it needed to do and made my dive unnecessarily short in one instance and more dangerous in the other. I am not sure why that is good.

 

[rivers]

I can find nothing in the manual about the computer adjusting for water temp? I don't think that is true. .

Don't go Luddite on us rivers.

All of my dives have a fairly square profile and for the most part I use min deco calculations to plan my dives (unless I've planned for a bit of deco, then i use baltic). In the off chance i go away to somewhere warm on holiday and end up doing a multi level rec dive, i'll probably switch my vyper back into computer mode

 

[JohnN]

Moreover, our divers are getting older. Older divers have an increased risk of DCS.

You seem to be a wealth of "facts":

From Risk factors for Decompression Accidents

• 
  [*=left][SIZE=+1]Age: The older diver has long been thought to be have increased tendencies to have DCS. Studies done by the Navy show a definite increase in DCS in older divers (all under 50 years of age). Other studies have not borne this out. Older divers have a higher percentage of body fat. Age and obesity: risk possibly increases in proportion to increase in age. Greater age and higher fat content are traditionally associated with increased incidence of DCS but the evidence is not consistent, recent reports showing no relationship.[/SIZE]

 

[beaverdivers]

You seem to be a wealth of "facts":

From Risk factors for Decompression Accidents

• 
  [*=left][SIZE=+1]Age: The older diver has long been thought to be have increased tendencies to have DCS. Studies done by the Navy show a definite increase in DCS in older divers (all under 50 years of age). Other studies have not borne this out. Older divers have a higher percentage of body fat. Age and obesity: risk possibly increases in proportion to increase in age. Greater age and higher fat content are traditionally associated with increased incidence of DCS but the evidence is not consistent, recent reports showing no relationship.[/SIZE]

Age
Generally, older people are at an increased risk of Decompression Sickness. This is due to less efficient circulatory and respiratory systems.

References

PADI, ​

Encyclopedia of Recreational Diving, 3rd Edition.

 

[Dr. Lecter]

Yes, I lead our divers on SCUBA trips to remote destinations all over the world. I feel that we need to use the latest & best methods available from Scubapro, but not anything more advanced, to avoid DCS.

Fixed that for you; carry on.

 

[boulderjohn]

What really bothers me is that neither heart rate nor respiratory rate is a good measure of workload. Both can be elevated by many things other than exertion, ...

and they can vary by the individual.

How does the algorithm interpret heart rate? DO you know?

My wife and I used to exercise at a recreation center on side by side machines that measured heart rates. Mine started at its usual level in the mid to low 40s. Hers started in its usual level in the mid to low 70s. As we got into the beginning of the exercise, hers would get over 100 pretty quickly. Mine would go into the 70s. If I maintained a pretty decent level of work load throughout the exercise, I would reach the high 80s, while hers would be well over 120. If I was working extremely hard, I could get it up to maybe 110. I would have to really scream to get up over 120. When I did a stress test a couple of years ago, I had to go into a flat out run on the treadmill to reach my target heart rate. My wife could do it with a stroll.

So if my wife and I were doing identical dives in terms of workload, how would the computer interpret those heart rates? How would it adjust our profiles?

 

[redacted]

You seem to be a wealth of "facts":

From Risk factors for Decompression Accidents

• 
  [*=left][SIZE=+1]Age: The older diver has long been thought to be have increased tendencies to have DCS. Studies done by the Navy show a definite increase in DCS in older divers (all under 50 years of age). Other studies have not borne this out. Older divers have a higher percentage of body fat. Age and obesity: risk possibly increases in proportion to increase in age. Greater age and higher fat content are traditionally associated with increased incidence of DCS but the evidence is not consistent, recent reports showing no relationship.[/SIZE]

Age
Generally, older people are at an increased risk of Decompression Sickness. This is due to less efficient circulatory and respiratory systems.

References

PADI, ​

Encyclopedia of Recreational Diving, 3rd Edition.

I guess it come down to the question of who is more credible in this field???

Curriculum Vitae for Ernest S Campbell, MD, FACS

or

About PADI

 

[GrimSleeper]

I can find nothing in the manual about the computer adjusting for water temp? I don't think that is true. .

Don't go Luddite on us rivers.

That's not fair. Where were you when I was begging to be called a Luddite 100-odd posts ago, herbdb?

---------- Post added September 13th, 2013 at 05:16 AM ----------

I guess it come down to the question of who is more credible in this field???

Curriculum Vitae for Ernest S Campbell, MD, FACS

or

About PADI

You're trying to do that "using science vs using-something-somebody-made-up-but-it-suits-my-argument" thing again, aren't you? Hasn't been wildly successful so far...

 

[beaverdivers]

After reading in "Deco for divers" about the "silent" bubbles, it dawned on me that after I started to be really OCD-ish about safety stops and slow ascents the last two-three meters, I experienced a lot less of the post-dive fatigue/drowsiness I originally assumed was more or less an obligatory consequence of diving. Food for thought, eh?

Some of the Uwatec computers allow for you to set a Micro-Bubble ( MB ) level between 5 different settings depending on which level of conservatism you choose. The ZHL8 ADT MB algorithm reduces the formation of micro-bubbles based on the MB level.

 

[lowviz]

"Micro-bubble" bull**** piled on top of bull****. It is all about bubbles in your blood and tissues.

You either stay well away from the NDL, or you learn to deal with what happens to YOU if you cross the line for any reason. Simple protocols exist for for akward escapes. If you dance on the line, as I often choose to do, I strongly recommend that you extend the "optional" final stop and SLOW DOWN on the final ascent.

If you are a diver, act like one. Not like someone who just wants to get back on the boat...