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easyrider003
06-05-2008, 13:01
I have purchased the Oceanic Veo 100 nx dive computer not long ago. Have read throught the manual and can't seem to find anywhere that it explains the PO2 / FO2 settings. I am not diving Nitrox, just air. What should I have these settings set too? Any input would be greatly appreciated.

Rainer
06-05-2008, 13:04
Air = .21
PPO2 = 1.2-1.4 (you choose).

easyrider003
06-05-2008, 16:00
This may be a stupid a question but what is "po2" / "fo2?"

Rainer
06-05-2008, 16:01
Fraction of O2 in a mix
Partial pressure of O2 in a mix

wgt
06-05-2008, 16:19
To put it another way, the Fraction of Oxygen (FO2) is given as a proportion. Oxygen constitutes approximately 21% of the air we are breathing. Therefore, the FO2 in air is .21.

Pressure of Oxygen (PO2) is a slightly more complicated concept, as it is dynamic, varying with ambient pressure. The first factor in computing PO2 is the FO2. The second factor is the pressure at which the gas is being breathed. The PO2 is therefore the mathematical product of the FO2 and the total ambient pressure in absolute atmospheres (ATA). Above water at sea level, the total ambient pressure is 1.0 ATA. Breathing air at sea level yields a breathing mix with FO2 of .21. To calculate the PO2, simply multiply FO2 X Ambient Pressure, which is .21 X 1.0 ATA = .21 ATA. If you breathe the same gas mix (air) with its FO2 of .21 at 10 meters (or about 33 feet) of sea water, then PO2 will double, as the total ambient pressure has doubled from 1 ATA to 2 ATA, while the FO2 has remained constant:

PO2 = FO2 X Ambient Pressure = .21 X 2.0 ATA = .42 ATA.

rawalker
06-05-2008, 16:49
It is for setting the Nitrox mix that you are using and at what point of Oxygen partial pressure load you want an alarm.

oddbod
06-06-2008, 08:27
Put simply if diving on air ( O2 21% + N2 79%) the FO2 is 21% and PO2, which is the max. depth the mixture ie:air 21%, can be used safely at can be set at 1.2 very conservative, 1.3 slightly conservative, 1.4 conservative, 1.5 risky and 1.6 oops too far.
These depths (approx. 160-220 feet) really don't matter for air as they are too deep for recreational diving anyway, but do matter when using nitrox mixes above 21% otherwise you may get what is called oxygen toxicity, which is caused by the increase in the partial pressure of O2, and apparently isn't very nice and often fatal.
P.S. The PO2 levels above are for illustrative purposes only and everyone can use their own safety scale!:smilie40:

mitsuguy
06-06-2008, 11:05
I don't want to start any arguments about pO2 here, but navy divers use 1.8 in training, 2.0 as a regular working limit, and 3.0 in mission critical operations... 1.4 is very safe, my alarm is set at 1.5, and 1.6 is getting there...

Might now be a bad idea to enroll in a nitrox course so you can have it all taught to you... Or, the info/ books are out there to read all about it...

Rainer
06-06-2008, 11:52
I don't want to start any arguments about pO2 here, but navy divers use 1.8 in training, 2.0 as a regular working limit, and 3.0 in mission critical operations... 1.4 is very safe, my alarm is set at 1.5, and 1.6 is getting there...

Might now be a bad idea to enroll in a nitrox course so you can have it all taught to you... Or, the info/ books are out there to read all about it...

Wrong. Like completely. Other than seals on O2 rebreathers under war time contingencies, the US Navy works at a PP02 of 1.3. That's right, MORE conservative than most recreational training agencies. Try to get your stuff right. THIS is precisely why you shouldn't become an instructor after this summer. You'd be an idiot if you consistently dive at 1.6.

mitsuguy
06-06-2008, 12:19
There is a slight chance I have my numbers wrong, as its been a year since I read the navy dive manual, but those were the same numbers re iterated to me by two different instructors, one an ex-navy diver... Also NOAA limit is 1.6 or 1.8... And no, I wouldn't dive with that all the time, as build up is something to worry about, but for short term, I see no issue with it, and obviously several regulating agencies don't either... When I get home tonight I'll look it up in the navy dive manual, see what I can find... In the mean time, leave me alone... Until you dive with me, you cannot make any judgements about my training, my skills, or anything else in life... Just like I don't make judgements about you... And as far as instructor, that will be next year... And until then, I will probably have more dives per week than you have per month...

fisheater
06-06-2008, 12:29
Gentlemen! This is the ScubaToys board. Not the "other board."

Please keep on topic and off of personal issues.

Thanks.

ianr33
06-06-2008, 13:25
Also NOAA limit is 1.6 or 1.8... And no, I wouldn't dive with that all the time, as build up is something to worry about, but for short term, I see no issue with it, and obviously several regulating agencies don't either..

I have no idea what the NOAA limit is but..................what is the point of using a PO2 greater than 1.4 during the bottom portion of a dive? What possible advantage is there to doing that?

Rainer
06-06-2008, 15:09
There is a slight chance I have my numbers wrong, as its been a year since I read the navy dive manual, but those were the same numbers re iterated to me by two different instructors, one an ex-navy diver... Also NOAA limit is 1.6 or 1.8... And no, I wouldn't dive with that all the time, as build up is something to worry about, but for short term, I see no issue with it, and obviously several regulating agencies don't either... When I get home tonight I'll look it up in the navy dive manual, see what I can find... In the mean time, leave me alone... Until you dive with me, you cannot make any judgements about my training, my skills, or anything else in life... Just like I don't make judgements about you... And as far as instructor, that will be next year... And until then, I will probably have more dives per week than you have per month...

Of course your Navy numbers are wrong. Not even close. You don't really seem to know what you're talking about. Maybe time for more reading less posting? Please also show me where NOAA has 1.8 as recommended for the working portion of the dive. Sounds like you've got some "great" instructors...

And let's see, in the past two weeks I have 17 dives in local NE waters (average temp in the low 40s). I'm sure that doesn't compare to your quarry diving. Or your internet diving.

Rainer
06-06-2008, 15:10
Also NOAA limit is 1.6 or 1.8... And no, I wouldn't dive with that all the time, as build up is something to worry about, but for short term, I see no issue with it, and obviously several regulating agencies don't either..

I have no idea what the NOAA limit is but..................what is the point of using a PO2 greater than 1.4 during the bottom portion of a dive? What possible advantage is there to doing that?

None. But then, you have to actually understand what this stuff means. There isn't an agency around that recommends 1.8 for the working portion of a dive (nor 1.6). As you say, Ian, it just doesn't make a lick of sense.

waytooslow
06-06-2008, 15:14
my dogs better than you dog...... J/K

Splitlip
06-07-2008, 08:39
Gentlemen! This is the ScubaToys board. Not the "other board."

Please keep on topic and off of personal issues.

Thanks.
http://i221.photobucket.com/albums/dd115/yj-jeepthing/CJ7OFFROAD/COMEDY.gif

mitsuguy
06-07-2008, 08:44
None. But then, you have to actually understand what this stuff means. There isn't an agency around that recommends 1.8 for the working portion of a dive (nor 1.6). As you say, Ian, it just doesn't make a lick of sense.

Actually, I didn't get a chance to look at the navy dive manual last night for very long - had to do our EFR class, however, I did take a brief look at the NAUI Nitrox book - working pO2 level for NOAA is 1.6, Navy Decompression pO2 is 2.2 for in water deco...

The reality of it is that all of these numbers are fairly conservative...

That's all I'm going to say as I do not want to start a fight...

Splitlip
06-07-2008, 08:48
Let's just not confuse "Fo2" with "Foo2".

wgt
06-07-2008, 11:25
This may be a stupid a question but what is "po2" / "fo2?"

Easyrider: It looks like we're getting a bit off track here. PM me if you think I might be able to help with your questions.

Rainer
06-07-2008, 16:13
None. But then, you have to actually understand what this stuff means. There isn't an agency around that recommends 1.8 for the working portion of a dive (nor 1.6). As you say, Ian, it just doesn't make a lick of sense.

Actually, I didn't get a chance to look at the navy dive manual last night for very long - had to do our EFR class, however, I did take a brief look at the NAUI Nitrox book - working pO2 level for NOAA is 1.6, Navy Decompression pO2 is 2.2 for in water deco...

The reality of it is that all of these numbers are fairly conservative...

That's all I'm going to say as I do not want to start a fight...

What does in water deco levels (with surface support...) have to do with working PPO2 on the bottom?

mitsuguy
06-07-2008, 17:23
None. But then, you have to actually understand what this stuff means. There isn't an agency around that recommends 1.8 for the working portion of a dive (nor 1.6). As you say, Ian, it just doesn't make a lick of sense.

Actually, I didn't get a chance to look at the navy dive manual last night for very long - had to do our EFR class, however, I did take a brief look at the NAUI Nitrox book - working pO2 level for NOAA is 1.6, Navy Decompression pO2 is 2.2 for in water deco...

The reality of it is that all of these numbers are fairly conservative...

That's all I'm going to say as I do not want to start a fight...

What does in water deco levels (with surface support...) have to do with working PPO2 on the bottom?

it doesn't, just an example I found... I'll find more info, as I DIDNT GET A CHANCE TO LOOK for the exact info last night... good lord, can you drop the attitude?

awap
06-07-2008, 17:54
An extract of the 4th edition of the NOAA Diving Manual :

15.5.2 Oxygen Exposure Time.
....
"Nitrox dives are planned with PO2 levels not exceeding 1.6 ata, though a slightly lower level provides less oxygen exposure risk. These levels provide significant single exposure bottom time with relatively low risk of oxygen toxicity."

Den7
04-04-2010, 01:18
Gentlemen,

I am not an expert in diving as I do it for fun only but I think you are making it more complicated than it really is. My Oceanic computer's manual has the following table which refers to Oceanic products and NOAA. I tend to trust these both organizations. If you do not exceed the limits you are safe is that not right? Just don't sit under water for 3 hours for exmple at your PO2 at 1.40 ATA. I guess this is so simple to follow this table... Is it not? I'd also strongly recommend to read your gear manuals carefully first. Usually it's all explained in there. Haste normally makes waste as they say. However, I found WGT's (your member's name) comments on the subject quite encyclopedical and very useful. :smiley20:

Oxygen Exposure Limits From NOAA (National Oceanic and Atmospheric Administration) Diving Manual

______Max duration ____Max Total Duration
PO2 _Single Exposure ____24 Hour Day
ATA __(min) (hrs) _______(min) (hrs)
---- --------------- -------------------
0.60 __720 12.0 _________720 12.0
0.70 __570 9.5 __________570 9.5
0.80 __450 7.5 __________450 7.5
0.90 __360 6.0 __________360 6.0
1.00 __300 5.0 __________300 5.0
1.10 __240 4.0 __________270 4.5
1.20 __210 3.5 __________240 4.0
1.30 __180 3.0 __________210 3.5
1.40 __150 2.5 __________180 3.0
1.50 __120 2.0 __________180 3.0
1.60 __45 .75 ___________150 2.0

Rorschach
04-04-2010, 03:47
I can't speak for USN in-water re/decompression but our ANDI training materials regarding in-water re/decompression from Australia, where multi-day liveaboard excursions far from hyperbaric chambers is common. No mention of surface support per se, this mandates in-water support / assistance at all times by other divers during in-water re/decompression.

Our ANDI tech training specified a max upper pN2 limit of 4.5 ATA, we're up to the last cert limit before heluim needs to be added to the mix, so binary O2 / N2 mixtures only. Our cert is good for 165 fsw (6 ATA), so if you apply 4.5 ATA pN2, thus leaves pO2 at 1.5 ATA at 6 ATA depth and constrains to EAN25 for that depth.

Our ANDI training stressed that above 1.4 pO2 up to 1.6 ATA O2 was the "caution zone", anything beyond 1.6 pO2 was for emergency bailout only for extremely short duration of up to 2.0 pO2. Our ANDI training used 1.45 po2 as standard for dive planning, then subtracting 0.05 pO2 per extra dive stress factor cumulatively. (working dive would be one, cold water would be one, etc). I can easliy see enough stress factors to easily reach 1.3 ATA pO2 max for in-water re/decompression given the additional stress factors involved.

I haven't yet come across a typical Nitrox dive computer that lets you set configurable po2 alarms in increments of 0.05 ATA. However, I can tell you that when we traveled to Saba, when we were diving EAN32 there were numerous dives where the 1.4 pO2 alarm would constantly drift in & out right at the base of the mooring line, near the top of the pinnacle. It would have been nice to have had EAN28 available on Saba but that wasn't the case.

Used to be you could access the NOAA diving manual at this site, but that link isn't working now - hopefully this link will work again at some point in time.

http://www.ndc.noaa.gov/pdfs/NOAA_Scientific_Dive_Manual.pdf

Den7
04-04-2010, 03:55
Hello there!

I have another question for experts about FO2. I dive on "air". My computer is always fixed to be on air with FO2 of 21%. However, it shows a different FO2 value at the end of each dive (it's all logged). Does any professional know how does that happen? :smiley6: As far as I understand the FO2 value is constant and it can not possibly change during the dive in any way even after I breathe off almost everything up to 50 bars. I have a wrist computer without any wireless transmitters to monitor my tank. The tank is always filled by a certified PADI shop so I doubt the problem occurs at re-filling. Any suggestions? Thanks.

Rorschach
04-04-2010, 04:01
Hello there!

I have another question for experts about FO2. I dive on "air". My computer is always fixed to be on air with FO2 of 21%. However, it shows a different FO2 value at the end of each dive (it's all logged). Does any professional know how does that happen? :smiley6: As far as I understand the FO2 value is constant and it can not possibly change during the dive in any way even after I breathe off almost everything up to 50 bars. I have a wrist computer without any wireless transmitters to monitor my tank. The tank is always filled by a certified PADI shop so I doubt the problem occurs at re-filling. Any suggestions? Thanks.

I agree, the fO2 in a single tank should not change during the dive - the remaining gas proportions at the end of a dive in the tank should be in the same proportions as before the dive.

What brand and model of dive computer are you using?

Have you tried contacting the computer brand service support folks?

Some dive computers will go into a 'default' mode after a dive, to ensure you set the gas mix for the next dive correctly. Some will assume 50% oxygen and 79% nitrogen in this mode, others default to 99% oxygen and 79% nitrogen when in this mode. Check your dive computer's manual to see if yours has this feature.

Den7
04-04-2010, 04:12
Our ANDI training stressed that above 1.4 pO2 up to 1.6 ATA O2 was the "caution zone", anything beyond 1.6 pO2 was for emergency bailout only

totally agree on above

I haven't yet come across a typical Nitrox dive computer that lets you set configurable po2 alarms in increments of 0.05 ATA.

Haven't yet seen those too


I agree but tech dives are a whole lot different from recrational :smiley2:

Rorschach
04-04-2010, 04:14
You see my point.

But do you understand where the pO2 of 1.6 on the table is at the high end of the 'cation zone" and 1.4 is below the low end of the caution zone?

Did you know this same math was true when we got our ANDI CSU-2 rec nitrox certs as it was when we got our ANDI TSD-3 beginner tech certs?

Plus, even NOAA has fatalities

http://www.ndc.noaa.gov/pdfs/090508_Dive_Fatality_Final_Report_public.pdf

Den7
04-04-2010, 04:39
I agree, the fO2 in a single tank should not change during the dive - the remaining gas proportions at the end of a dive in the tank should be in the same proportions as before the dive.

What brand and model of dive computer are you using?

I use Oceanic VEO 3.0

Have you tried contacting the computer brand service support folks?

Not yet. Will that actually help? I think it will take forever for someone as big as Oceanic to reply to a question of a simple person... They prefer big corporations, huge companies, one million people dive centers... and here is someone small... I doubt they will even bother to read my message...

Some dive computers will go into a 'default' mode after a dive, to ensure you set the gas mix for the next dive correctly. Some will assume 50% oxygen and 79% nitrogen in this mode, others default to 99% oxygen and 79% nitrogen when in this mode. Check your dive computer's manual to see if yours has this feature.

It has this feature but also says the following,
"When the FO2 50% default is set off, FO2 will remain set at the last gas 1 set point saved during that period of activation. The default FO2 setting for gas 1 each new activation period will be air of FO2 = 21%". Therefore according to the manual quoted above I am always supposed to be on "air". But how does that help me to figure out why FO2 values change at the end of dives?


My comments are above in red. :smiley2:

mitsuguy
04-04-2010, 04:50
Not yet. Will that actually help? I think it will take forever for someone as big as Oceanic to reply to a question of a simple person... They prefer big corporations, huge companies, one million people dive centers... and here is someone small... I doubt they will even bother to read my message...

man its been a long time since this post was originally made...

not gonna get into the other arguments again, however, I can tell you that Oceanic is an awesome company with great customer support... If you call them with questions, you are generally never on hold for more than a minute or two... I've also received e-mails back (personalized, not a stock e-mail) within hours of e-mailing them...

Den7
04-04-2010, 05:10
You see my point.

But do you understand where the pO2 of 1.6 on the table is at the high end of the 'cation zone" and 1.4 is below the low end of the caution zone?

Well, I think the math in diving is too simple everywhere for example starting from 1.4ATA x 21% = 29.4 meters up to 1.6 ATA x 21% = 33.6 meters. This is the range of your caution zone (from 29.4 meters up to 33.6 meters or the same in would be from 96.45 feet up to 110.23 feet). Is it that what you were trying to say? I am not an expert of course, this is just my guess. :smiley2:

Did you know this same math was true when we got our ANDI CSU-2 rec nitrox certs as it was when we got our ANDI TSD-3 beginner tech certs?

Plus, even NOAA has fatalities

I am not saying the NOAA is perfect. Unfortunately fatalities happen everywhere...

http://www.ndc.noaa.gov/pdfs/090508_Dive_Fatality_Final_Report_public.pdf

My comments are above in red. :icon_lol:

comet24
04-04-2010, 05:16
Holly thread resurrections Batman. Until today the last time this thread was posted to was 06-07-2008.

Den7
04-04-2010, 05:21
Not yet. Will that actually help? I think it will take forever for someone as big as Oceanic to reply to a question of a simple person... They prefer big corporations, huge companies, one million people dive centers... and here is someone small... I doubt they will even bother to read my message...

man its been a long time since this post was originally made...

not gonna get into the other arguments again, however, I can tell you that Oceanic is an awesome company with great customer support... If you call them with questions, you are generally never on hold for more than a minute or two... I've also received e-mails back (personalized, not a stock e-mail) within hours of e-mailing them...

yep, it's been a long time...

Well, I am not really sure about Oceanic in the US and I believe you mitsuguy. Probably they are good where you are at. I tried once to contact Oceanic in Germany and have been waiting for their reply for the second month now despite my reminders and all... Could you share the contact of those who you got in touch with and with that awsome customer support? Would really appreciate it.

mitsuguy
04-04-2010, 05:26
Not yet. Will that actually help? I think it will take forever for someone as big as Oceanic to reply to a question of a simple person... They prefer big corporations, huge companies, one million people dive centers... and here is someone small... I doubt they will even bother to read my message...

man its been a long time since this post was originally made...

not gonna get into the other arguments again, however, I can tell you that Oceanic is an awesome company with great customer support... If you call them with questions, you are generally never on hold for more than a minute or two... I've also received e-mails back (personalized, not a stock e-mail) within hours of e-mailing them...

yep, it's been a long time...

Well, I am not really sure about Oceanic in the US and I believe you mitsuguy. Probably they are good where you are at. I tried once to contact Oceanic in Germany and have been waiting for their reply for the second month now despite my reminders and all... Could you share the contact of those who you got in touch with and with that awsome customer support? Would really appreciate it.

perhaps just try the US link instead... Oceanic Worldwide - Contact Oceanic (http://www.oceanicworldwide.com/index_contact.html)

Den7
04-04-2010, 05:53
thanks. Will try someone from the US. :smiley2:

Rorschach
04-04-2010, 12:17
You see my point.

But do you understand where the pO2 of 1.6 on the table is at the high end of the 'cation zone" and 1.4 is below the low end of the caution zone?

Well, I think the math in diving is too simple everywhere for example starting from 1.4ATA x 21% = 29.4 meters up to 1.6 ATA x 21% = 33.6 meters. This is the range of your caution zone (from 29.4 meters up to 33.6 meters or the same in would be from 96.45 feet up to 110.23 feet). Is it that what you were trying to say? I am not an expert of course, this is just my guess. :smiley2:

Did you know this same math was true when we got our ANDI CSU-2 rec nitrox certs as it was when we got our ANDI TSD-3 beginner tech certs?

Plus, even NOAA has fatalities

I am not saying the NOAA is perfect. Unfortunately fatalities happen everywhere...

http://www.ndc.noaa.gov/pdfs/090508_Dive_Fatality_Final_Report_public.pdf

My comments are above in red. :icon_lol:

Noted. Do you know EAN can range from 25% O2 to 99% O2?

So, can you explain why you choose only two of those options - are 21%, 32% and 36% the only three O2 %'s your computer is programmed for? What happens when you get a tank of "EAN32" that tests to be 30.1% O2 from the fill station? Or a tank of "EAN36' that tests at 37.8% O2? Would you slavishly write the same MOD's you put in red in the nitrox tank log sheet at the fill station? Would you still just program your computer for 32% or 36%? If not, would you expect your computer's pO2 alarm to go off at the same depth as you've put in red?

Now do you see the math applies for more than just 3 selections?

There are two issues - one is the whole body toxicity in the first post you made in this thread, the other is CNS, which different individuals and different agencies seem to enjoy endlessly argiung about. The CNS issue is why your post earlier in this thread (post#23) is only seeing half the picture.

It's in that same post you advise people to check their gear manuals. :smiley2:

I know how the make & model dive computers I own work, and if any of the 3 I own wasn't working the way I expected, I wouldn't use it for diving - I'd contact the manufacturer This is part of the reason I own 3 dive computers - I don't want a computer failure to hose me on a diving trip where I'd have to wait 24 - 48 hours if something happened.

see my post #26 for contacting the manufacturer - I agree with mitsuguy Oceanic has a great reputation for customer service.

Jack Hammer
04-04-2010, 13:47
Holly thread resurrections Batman. Until today the last time this thread was posted to was 06-07-2008.
That's not bad, I didn't notice the dates and just reported a 2 year old post in the thread.:smiley29:

There is a lot of useful info that's missing here, however this is one of those threads that should have stayed dead and just been replaced with a one.

Splitlip
04-04-2010, 18:43
What about Foo2?

navyhmc
04-05-2010, 02:26
What about Foo2?

Do not say that name! Even the mere mention of it can bring her wrath upon all of us! :smiley36:

What about foo2? Foo!

Foo2
04-05-2010, 08:23
What about Foo2?

Do not say that name! Even the mere mention of it can bring her wrath upon all of us! :smiley36:

What about foo2? Foo!
:lin:

Den7
04-11-2010, 00:11
Noted. Do you know EAN can range from 25% O2 to 99% O2?

So, can you explain why you choose only two of those options - are 21%, 32% and 36% the only three O2 %'s your computer is programmed for? What happens when you get a tank of "EAN32" that tests to be 30.1% O2 from the fill station? Or a tank of "EAN36' that tests at 37.8% O2? Would you slavishly write the same MOD's you put in red in the nitrox tank log sheet at the fill station? Would you still just program your computer for 32% or 36%? If not, would you expect your computer's pO2 alarm to go off at the same depth as you've put in red?

Now do you see the math applies for more than just 3 selections?

There are two issues - one is the whole body toxicity in the first post you made in this thread, the other is CNS, which different individuals and different agencies seem to enjoy endlessly argiung about. The CNS issue is why your post earlier in this thread (post#23) is only seeing half the picture.

It's in that same post you advise people to check their gear manuals. :smiley2:

I know how the make & model dive computers I own work, and if any of the 3 I own wasn't working the way I expected, I wouldn't use it for diving - I'd contact the manufacturer This is part of the reason I own 3 dive computers - I don't want a computer failure to hose me on a diving trip where I'd have to wait 24 - 48 hours if something happened.

see my post #26 for contacting the manufacturer - I agree with mitsuguy Oceanic has a great reputation for customer service.

Well, I am a very brand-new diver and I am not really sure what to tell you. I am not even nitrox certified, let alone tech diving. I simply read on the subject just to be awaare of what it is all about. The aspect I was interested in was pure mathematics and diving medicine. But since it's pretty hard to tell how to cure diseases without knowing the cause of them I simply went through reading for the beginning.

Let me tell you you a few jokes about "being on the safe side".

"A kid with a 4 pockets jacket gets on a bus for a bout 30 minutes trip to go visit his granny. He buys a ticket, puts it in the first pocket, and takes a seat. Then in a little while he stands up, goes buy another ticket and puts it into his second pocket. Then some time later he stands up again and buys the third ticket and puts it into his third pocket. An old co-traveller man who was watching the kid all the time says,
-Listen, sonny, why did you buy a second ticket if you already had one?
-This is in case I might lose my first one,- replies the kid.
-Then why on earth did you buy the third one?- continues the old man.
-This is in case I lose the first two tickets!- loudly answers the kid.
Then the old man begins to laugh and says,
-What will happen if you lose all your three tickets?
-And for this case,- says the kid opening his fouth pocket and getting something out of it,- I have my "monthly fare paid in advance" fourth ticket!- happily exclaims the boy.
The old mian falls unconsious." :smiley36:

There are people who love to go for overkill to be on a safe side but I would have never thought of buying 5 computers just in case my first 4 had failed. :smiley9: No ofence meant. I like to be real safe and conservative too so perhaps I'll think about having some extra precautions in regards of my dive computers as well.

Now as far as mathematics concerns for your 3 selections I would guess that you may need to have your main constants defined first as mathematics' algorithms are normally based on that which in turn is the core and "saint" rule of dive computers. Then having those constants defined you will have it easily calculated. Additionally in my opinion you would have to choose whether to go for either conservative settings to have more security and less bottom time or less safe settings with accordingly less security and more bottom time... You divide, define, calculate, weigh, pick out, set, go. This is what I would do but let me say again that I am not a professional and this is only what logic tells me for the moment based on the divng knowledge I have gained up to now. :smiley31:

Rorschach
04-11-2010, 11:03
Ah, this explains a lot; you'll learn quite a bit when you choose to take training to use nitrox. I am a professional, but scuba diving isn't my profession. My profession does rely heavily on gas behavior and mathematics.

Den7
04-13-2010, 05:49
Not yet. Will that actually help? I think it will take forever for someone as big as Oceanic to reply to a question of a simple person... They prefer big corporations, huge companies, one million people dive centers... and here is someone small... I doubt they will even bother to read my message...


not gonna get into the other arguments again, however, I can tell you that Oceanic is an awesome company with great customer support... If you call them with questions, you are generally never on hold for more than a minute or two... I've also received e-mails back (personalized, not a stock e-mail) within hours of e-mailing them...


perhaps just try the US link instead... Oceanic Worldwide - Contact Oceanic (http://www.oceanicworldwide.com/index_contact.html)

Hey mitsuguy, I hate to disappoint you but all the US Oceanic could tell me was, "thank you for choosing and buying our products." This e-mail has also been personalized. But that was it... I have been waiting for an answer to my question (not just any stupid answer) from them ever since... It's been more than a week now... :smiley21: :smiley6:

mitsuguy
04-13-2010, 06:31
Not yet. Will that actually help? I think it will take forever for someone as big as Oceanic to reply to a question of a simple person... They prefer big corporations, huge companies, one million people dive centers... and here is someone small... I doubt they will even bother to read my message...


not gonna get into the other arguments again, however, I can tell you that Oceanic is an awesome company with great customer support... If you call them with questions, you are generally never on hold for more than a minute or two... I've also received e-mails back (personalized, not a stock e-mail) within hours of e-mailing them...


perhaps just try the US link instead... Oceanic Worldwide - Contact Oceanic (http://www.oceanicworldwide.com/index_contact.html)

Hey mitsuguy, I hate to disappoint you but all the US Oceanic could tell me was, "thank you for choosing and buying our products." This e-mail has also been personalized. But that was it... I have been waiting for an answer to my question (not just any stupid answer) from them ever since... It's been more than a week now... :smiley21: :smiley6:

Hmmm, interesting... I can show you at least a dozen e-mails with Oceanic, all within 24-48 hours of the original message to them... what'd you do to piss them off huh???? j/k :)

Den7
04-13-2010, 06:49
Not yet. Will that actually help? I think it will take forever for someone as big as Oceanic to reply to a question of a simple person... They prefer big corporations, huge companies, one million people dive centers... and here is someone small... I doubt they will even bother to read my message...


not gonna get into the other arguments again, however, I can tell you that Oceanic is an awesome company with great customer support... If you call them with questions, you are generally never on hold for more than a minute or two... I've also received e-mails back (personalized, not a stock e-mail) within hours of e-mailing them...


perhaps just try the US link instead... Oceanic Worldwide - Contact Oceanic (http://www.oceanicworldwide.com/index_contact.html)

Hey mitsuguy, I hate to disappoint you but all the US Oceanic could tell me was, "thank you for choosing and buying our products." This e-mail has also been personalized. But that was it... I have been waiting for an answer to my question (not just any stupid answer) from them ever since... It's been more than a week now... :smiley21: :smiley6:

Hmmm, interesting... I can show you at least a dozen e-mails with Oceanic, all within 24-48 hours of the original message to them... what'd you do to piss them off huh???? j/k :)

Well, I guess they simply do not know the answer. hehehe :smiley29: They replied to me within 24 hours all right but the question was not answered. Most probably that's becasue I do not normally ask "waste-time" questions I think. First I extensively searched the Internet, learned the manual of my new dive computer almost by heart, reading it for so many times in hopes to understand where the heck the problem comes from, asked a dozen of dive instructors and dive masters but... nobody knows...

mitsuguy
04-13-2010, 07:11
so, on the Veo3.0, what does the display say? are you in Nitrox 21 or Air?

Den7
04-13-2010, 08:02
so, on the Veo3.0, what does the display say? are you in Nitrox 21 or Air?

Well, you might as well give it a try. Would appreciate any suggestions at all. Here is what I am asking (simplified version)

What does the "Log" mode show after a dive "on air" and which fraction of
FO2 (fraction of oxygen) does it suppose to show after a dive "on air" is finished?

...My Oceanic VEO 3.0 computer has FO2 always set on air. However, it shows the same FO2 value (FO2 = 13) at the end of each dive (it's all logged). I never set or change FO2 manually for any other values. As far as I
understand the FO2 value is constant (21% by default in this case) and
it can not possibly change during the dive in any way even after I
breathe off almost everything up to 50 bars/ 5000 psi. I have a wrist computer without any wireless transmitters to monitor my tank (I wish it was on this model though). The tank is always filled by a certified PADI shop so I
doubt the problem occurs at re-filling. Any suggestions? ...The
"SEt dFLt 50-OFF" is always set to OFF...

mitsuguy
04-14-2010, 05:40
so, on the Veo3.0, what does the display say? are you in Nitrox 21 or Air?


What does the "Log" mode show after a dive "on air" and which fraction of
FO2 (fraction of oxygen) does it suppose to show after a dive "on air" is finished?

...My Oceanic VEO 3.0 computer has FO2 always set on air. However, it shows the same FO2 value (FO2 = 13) at the end of each dive (it's all logged).

Ok, so, where are you seeing this F02 value? On the computer itself, or when you download the data to a home PC? I have a Veo sitting in the shop that I can look at when I get back later today hopefully... Is there any chance you can take a picture of it (on the wrist computer), or a screen shot (if its on your home PC) so that we can see exactly what you are talking about?

Den7
04-14-2010, 07:10
so, on the Veo3.0, what does the display say? are you in Nitrox 21 or Air?


What does the "Log" mode show after a dive "on air" and which fraction of
FO2 (fraction of oxygen) does it suppose to show after a dive "on air" is finished?

...My Oceanic VEO 3.0 computer has FO2 always set on air. However, it shows the same FO2 value (FO2 = 13) at the end of each dive (it's all logged).

Ok, so, where are you seeing this F02 value? On the computer itself, or when you download the data to a home PC? I have a Veo sitting in the shop that I can look at when I get back later today hopefully... Is there any chance you can take a picture of it (on the wrist computer), or a screen shot (if its on your home PC) so that we can see exactly what you are talking about?

Please, read it carefully. You ask again what is already said and written. It is AIR (not Nitrox)

Please, read it carefully. You ask again what is already said and written. The value FO2 = 13 is shown after EACH DIVE is finished. It is supposed to be 21%, not 13 in my opinion.

The data is shown onboard Oceanic VEO 3.0 (not on a regular computer).

Yes, I can take a picture of course and attach it here I guess. However, there are only three values shown in the log mode after each dive on air is finished. O2SAT = 0 as this is not Nitrox, PO2 MAX = 0 as this is not Nitrox, but FO2 = 13 for some reason (not 21?).

Noob
04-14-2010, 08:03
Here ya go dude

Oceanic Worldwide - Personal Dive Computers - Veo 100 Nx (http://www.oceanicworldwide.com/p_computers_veo100nx_manuals.html)

PG 15-21:smiley20:

Den7
04-14-2010, 09:07
Here ya go dude

Oceanic Worldwide - Personal Dive Computers - Veo 100 Nx (http://www.oceanicworldwide.com/p_computers_veo100nx_manuals.html)

PG 15-21:smiley20:

Another one who cannot read... Are you illiterate or something Noob? My computer is VEO 3.0, not VEO 100!

mitsuguy
04-14-2010, 09:15
Ok, so, where are you seeing this F02 value? On the computer itself, or when you download the data to a home PC? I have a Veo sitting in the shop that I can look at when I get back later today hopefully... Is there any chance you can take a picture of it (on the wrist computer), or a screen shot (if its on your home PC) so that we can see exactly what you are talking about?

Please, read it carefully. You ask again what is already said and written. It is AIR (not Nitrox)

Please, read it carefully. You ask again what is already said and written. The value FO2 = 13 is shown after EACH DIVE is finished. It is supposed to be 21%, not 13 in my opinion.

The data is shown onboard Oceanic VEO 3.0 (not on a regular computer).

Yes, I can take a picture of course and attach it here I guess. However, there are only three values shown in the log mode after each dive on air is finished. O2SAT = 0 as this is not Nitrox, PO2 MAX = 0 as this is not Nitrox, but FO2 = 13 for some reason (not 21?).[/QUOTE]

So, maybe this isn't why you are getting good responses. You are reacting negatively to assistance. I am just trying to clarify. Not once did you specifically say it was on the dive computer, as the logs can be viewed on a home PC as well... Also, O2Sat can increase over 0, even with air dives, as does PO2... In fact, the PO2 of air at 99 feet of water is .84 Spend enough time at depth, and O2Sat goes up...

Here is an idea... What are all of your optional gases set at??? are they all set at air??? I have attached a small jpg - are you at the same screen as what is shown??? Specifically, does it say NX or Air on the top, or nothing, at the top? Also, on the left, where the tank is, what number is there?

Noob
04-14-2010, 09:21
Here ya go dude

Oceanic Worldwide - Personal Dive Computers - Veo 100 Nx (http://www.oceanicworldwide.com/p_computers_veo100nx_manuals.html)

PG 15-21:smiley20:

Another one who cannot read... Are you illiterate or something Noob? My computer is VEO 3.0, not VEO 100!


"I have purchased the Oceanic Veo 100 nx dive computer not long ago. Have read throught the manual and can't seem to find anywhere that it explains the PO2 / FO2 settings. I am not diving Nitrox, just air. What should I have these settings set too? Any input would be greatly appreciated."

I dont know if I'm taking your remark wrong or what, but here is the original post. I do not see anywhere about a VEO 300, nor read 6 pages of remarks. I do not see where I am the illiterate one here. Instead of jumping to a conclusion and hijacking a thread start a new one.

For the original poster of this thread. The computer uses AIR setting default unless you go in and change it. I got that from pg 15. It works alot like my Veo 250

Den7
04-14-2010, 09:33
Ok, so, where are you seeing this F02 value? On the computer itself, or when you download the data to a home PC? I have a Veo sitting in the shop that I can look at when I get back later today hopefully... Is there any chance you can take a picture of it (on the wrist computer), or a screen shot (if its on your home PC) so that we can see exactly what you are talking about?

Please, read it carefully. You ask again what is already said and written. It is AIR (not Nitrox)

Please, read it carefully. You ask again what is already said and written. The value FO2 = 13 is shown after EACH DIVE is finished. It is supposed to be 21%, not 13 in my opinion.

The data is shown onboard Oceanic VEO 3.0 (not on a regular computer).

Yes, I can take a picture of course and attach it here I guess. However, there are only three values shown in the log mode after each dive on air is finished. O2SAT = 0 as this is not Nitrox, PO2 MAX = 0 as this is not Nitrox, but FO2 = 13 for some reason (not 21?).

So, maybe this isn't why you are getting good responses. You are reacting negatively to assistance. I am just trying to clarify. Not once did you specifically say it was on the dive computer, as the logs can be viewed on a home PC as well... Also, O2Sat can increase over 0, even with air dives, as does PO2... In fact, the PO2 of air at 99 feet of water is .84 Spend enough time at depth, and O2Sat goes up...

Here is an idea... What are all of your optional gases set at??? are they all set at air??? I have attached a small jpg - are you at the same screen as what is shown??? Specifically, does it say NX or Air on the top, or nothing, at the top? Also, on the left, where the tank is, what number is there?[/QUOTE]

I react like that because you are getting completely side tracked and do not seem to follow what I am talking about almost at all. No ofence meant, dude really. Please, never mind, forget about my question. I appreciate your try though. Thanks! :smiley20:

Den7
04-14-2010, 09:41
Here ya go dude

Oceanic Worldwide - Personal Dive Computers - Veo 100 Nx (http://www.oceanicworldwide.com/p_computers_veo100nx_manuals.html)

PG 15-21:smiley20:

Another one who cannot read... Are you illiterate or something Noob? My computer is VEO 3.0, not VEO 100!


"I have purchased the Oceanic Veo 100 nx dive computer not long ago. Have read throught the manual and can't seem to find anywhere that it explains the PO2 / FO2 settings. I am not diving Nitrox, just air. What should I have these settings set too? Any input would be greatly appreciated."

I dont know if I'm taking your remark wrong or what, but here is the original post. I do not see anywhere about a VEO 300, nor read 6 pages of remarks. I do not see where I am the illiterate one here. Instead of jumping to a conclusion and hijacking a thread start a new one.

For the original poster of this thread. The computer uses AIR setting default unless you go in and change it. I got that from pg 15. It works alot like my Veo 250

It looks like you jumped right in the middle of my discussion with mytsuguy Noob and I thought you were talking to me.. You said, "Here you go dude" and refered to some manuals. Please, ignore my remark then if you were trying to start a new thread. :smiley29:

Noob
04-14-2010, 09:48
It looks like you jumped right in the middle of my discussion with mytsuguy Noob and I thought you were talking to me.. You said, "Here you go dude" and refered to some manuals. Please, ignore my remark then if you were trying to start a new thread. :smiley29:

I should have put "To the original poster" That is my fault.

What post # is the question? I might be able to help.

mitsuguy
04-14-2010, 10:58
I react like that because you are getting completely side tracked and do not seem to follow what I am talking about almost at all. No ofence meant, dude really. Please, never mind, forget about my question. I appreciate your try though. Thanks! :smiley20:

In my previous life, I did troubleshooting... Very in depth, very confusing troubleshooting... Many times, I had people giving me what they thought was the problem, and I also had people telling me what they perceived the problem to be... Both of these are valuable, but at the same time, must be taken with a grain of salt...

So, when I can't see the problem for myself, I need to start at square 1, to take any sort of miscommunication out of the troubleshooting loop... Sometimes it isn't even a problem with the equipment at all, but instead its someone not understanding its use or application... Not saying you don't, but, I want to make sure that we are talking about the exact right thing...

I had planned on taking our Veo 3.0 out on a dive (in like 5 minutes) to observe its settings, but, no need I suppose now...

Jack Hammer
04-14-2010, 15:21
Den7 - Until you post a picture of your computer showing exactly what it is you are asking about people are going to have to try to visualize it for themselves. This means they are going to ask questions and try to cross basic issues off the list of potential problems. Getting snippy with those trying to help only serves to make you look bad and deter others from trying to help. If you only want experts to help you out then you may want to consider sending your computer to Oceanic and having them figure it out. Otherwise you may find you'll get a lot further by remaining patient and keeping your responses civil.

Rorschach
04-15-2010, 17:08
I saw Den7 had tacked a similar post on some other many-years-defunct thread on Scubaboard so I asked the SB Advisors to move that post to the Q&A for Scuba Manufacturers Oceanic sub-forum, which they did.

I don't see what else we can do here.