computer with transmitter and nodeco time

sorry for my bad english, but I know you have a very friendly attitude

I have a dubt:
computer with transmitter (do you understand my english? that wi-fi or consolle-style sensor from HP...) change nodeco limits according to how much you breath???

otherwise a traditional computer has shorter times than transmitter ones if have few air consumption???

I think that doesn't matter, anyway....
thanx!
m.

I'll try. Tell me if I've understood your question.

An air-integrated computer is aware of your gas consumption.
A 'traditional' dive computer is not.

The air integration can either be a direct HP hose to the dive computer, e.g., Suunto Cobra or Oceanic Pro Plus 2, or it can be a wireless connection between a transmitter on the 1st stage HP port and the computer, e,g., Suunto Vyper Air. Hose or wireless makes a difference in use and reliability (and cost) but they both accomplish the same thing - telling your computer what your current tank pressure is.

What does/can the computer do with the tank pressure?
- Replace the traditional SPG for the diver's in-dive monitoring of tank pressure.
- Estimate and display the remaining air time, based on the diver's consumption rate, to reduce the likelihood of an out-of-air situation.
- Present visible and audible alarms about low tank pressure to further reduce the likelihood of an out-of-air situation.
- Record the tank pressure, possibly at intervals over the dive as a profile, for later upload to a PC, for use in computing air consumption rates.

But what the computer doesn't do with the tank pressure is what you're asking about, which is affect the calculation of nitrogen loading, no-deco limits, etc. These are a function only of depth, time, and the %N2 in your breathing gas. Tank air consumption does not affect nitrogen loading.

What an 'integrated' computer will do is give you the shorter of two times: no-deco or remaining air time based upon your consumption. Often it's the latter which is displayed.

marcopalla: The ScubaPro Galileo Sol is a wireless AI (air integrated) computer that includes a heart rate monitor (HRM). I have 70+ dives on mine and love it. I interpret your question differently than reefduffer (who sounds like he really knows his stuff so I won't disagree) and will comment on RBT (remaining bottom time) as it relates to consumption. I was on a nitrox, no-deco profile dive and got really excited (I knew this because the HRM beeped at me since my heart rate was high), so i looked at my RBT of 6 minutes. I calmed down for 30 seconds and my RBT jumped up to 9 minutes. I recall this because I was happy that a 30 second 'spend' yielded 3 more minutes underwater. I am unsure exactly why it worked, but this is my best guess (having read the manual) - the Galileo Sol uses air consumption plus heart rate to calculate Oxygen toxicity (loading??) and monitor microbubbles (which are used in the algorithm) to calculate remaining no-deco time, which if less than consumption rate would be a better metric to monitor.

reefduffer: you clearly know quite a bit about this - does it sound correct that adding an HRM will facilitate the calculation you referenced?

marcopalla:

sorry for my bad english, but I know you have a very friendly attitude

I have a dubt:
computer with transmitter (do you understand my english? that wi-fi or consolle-style sensor from HP...) change nodeco limits according to how much you breath???

otherwise a traditional computer has shorter times than transmitter ones if have few air consumption???

I think that doesn't matter, anyway....
thanx!
m.

Click to expand...

I think your question (if I understand it correctly) has already been answered but just to keep the answer short...no, the no deco limits don't change whether you are using a traditional computer or whether you are using an air integrated computer.

The AI computer measures your breathing rate but breathing rate doesn't affect your NDL time. Time and depth affect your NDL time.

scuba.dude:

marcopalla: The ScubaPro Galileo Sol is a wireless AI (air integrated) computer that includes a heart rate monitor (HRM). I have 70+ dives on mine and love it. I interpret your question differently than reefduffer (who sounds like he really knows his stuff so I won't disagree) and will comment on RBT (remaining bottom time) as it relates to consumption. I was on a nitrox, no-deco profile dive and got really excited (I knew this because the HRM beeped at me since my heart rate was high), so i looked at my RBT of 6 minutes. I calmed down for 30 seconds and my RBT jumped up to 9 minutes. I recall this because I was happy that a 30 second 'spend' yielded 3 more minutes underwater. I am unsure exactly why it worked, but this is my best guess (having read the manual) - the Galileo Sol uses air consumption plus heart rate to calculate Oxygen toxicity (loading??) and monitor microbubbles (which are used in the algorithm) to calculate remaining no-deco time, which if less than consumption rate would be a better metric to monitor.

reefduffer: you clearly know quite a bit about this - does it sound correct that adding an HRM will facilitate the calculation you referenced?

Click to expand...

I think the heart rate monitor is more or less a gimmick. If it helps you to calm down then perhaps there is some use for it. I doubt if the results of the heart rate monitor affect the calculations in any meaningful way.

Measuring core body temp and perhaps percent body fat might be of some use but even then you'd really just have somewhat pertinent data with no real basis for using it since decompression science isn't that precise at this point.

The reason it "worked" in your scenario is just because when you saw your heart rate go up you realized that you needed to calm down. When you did that your breathing rate was lowered as well.

So you used less air (Nitrox in this case). When you did that of course the computer estimated that your remaining air would last longer at that rate.

The same thing would have happened without the heart rate monitor if you had realized that you needed to calm down and then did so.

Well, that turns out not to be the case ...

I downloaded the Galileo Sol manual, and quite a lot of what I've said in this thread turns out to be wrong. My education continues.

It turns out that the Sol models N2 loading including a metric of physical activity; briefly stated, it assumes that if you're more active you're absorbing N2 faster. I just hadn't encountered that concept before other than in the physiological sense, that you may want to reduce your bottom time if it's cold or under heavy exertion. I was unaware there were tables or computers that take it into account. My bad.

UWATEC introduced workload-induced decompression algorithm compensation in 1995 with the Aladin Air X dive computer. ...

As as starting point, they use air consumption rate, so that the OPs question needs to be answered "yes" rather than "no" for this line of computers, at least. Air consumption rate will affect no-deco time for this computer.

And for the Sol or others with a heart rate monitor, it can use that as the metric of exertion rather than air consumption.

Manual can be downloaded at GALILEO SOL - SCUBAPRO-UWATEC

The relevant description is section 2.9.5 starting on page 37.

scuba.dude's description of his experience, and his interpretation of it, seems like how his computer works.

Sorry for any confusion I've caused.

I'll correct my comments only to the extent of me not having personal knowledge of this particular computer however I still believe it's more or less a gimmick (HRM).

Regarding diving in cold water, most tables tell you to plan for a depth deeper than you will actually be diving if certain conditions apply (cold water is one of them). Core body temp and anything that improves circulation/blood flow will also affect n2 absorption and a colder core temp will at the end of a dive slow down offgassing.

This effect is why it's not a good idea to hop into a hot dive after a dive as you will be offgassing faster than you ongassed and this is outside of the perimeters of the model.

I'm sure if you attach a HRM to a dive computer then you have to make it effect the numbers somewhat just to justify the expense but I don't think it's really doing much to improve or personalize your safety. Just my opinion however.

marcopalla:

sorry for my bad english, but I know you have a very friendly attitude

I have a dubt:
computer with transmitter (do you understand my english? that wi-fi or consolle-style sensor from HP...) change nodeco limits according to how much you breath???

otherwise a traditional computer has shorter times than transmitter ones if have few air consumption???

I think that doesn't matter, anyway....
thanx!
m.

Click to expand...

Marco,
fai pure la domanda in Italiano ed io la traduco .... xche' in Inglese e' un po' confusa ....

Alberto (aka eDiver)