[Date Prev][Date Next]
[Chronological]
[Thread]
[Top]
Re: [PSUBS-MAILIST] Sgt. Peppers O2 consumption rate question.
Hi Stan,
SFreihof@aol.com schrieb:
>
> Just a few notes on the subject...
>
> O2 consumption is mostly dependent on workload and/or stress. Carsten's
> figure of 1/2 liter per minute is for a person at rest. Under exertion,
> consumption can rise as high as 2 liters/minute.
Thats right : Here are the tables:
02 consumption breath rate
- sitting without work 0,25 l/min 06,0 l/min
- going slow 0,65 l/min 15,0 l/min
- swimming slow 15m/min 0,75 l/min 17,5 l/min
- swimming fast 30m/min 1,75 l/min 39,0 l/min
- Running 12km/h 1,85 l/min 46,5 l/min
- swimming v.fast 40m/min 2,60 l/min 65,0 l/min
I think a diver should be the breath rate of swimming fast 30m/min
and a submadman in his close cycle sub can use a 02 consumption
rate of 0,25 - 0,5 l/min. Maybe on his first test dive more..
>
> Breathing is affected most by elevated carbon dioxide levels (partial
> pressure CO2 up to 0.05 atm) not by low oxygen levels. The discomfort you
> feel after 45 minutes in your unreplenished sub is not low oxygen, but high
> carbon dioxide. All things equal, I'd rather have my scrubber outlast my
> oxygen because I would rather go from low 02 (sleepy) than high CO2
> (suffocating).
Thats right. The scrubber should work longer than the 02 bottle
and you died very friendly - but headeges are a good indicator thats
something with your scrubber goes wrong. If you visible view goes
from wide angle to a small angle without headeges - thats the last
and maybe to late indication thats your 02 vale is close and
your scrubber is still working..
>
> None of this really applies to me. Since I'm into the ambient scene, I don't
> recycle... I just run out of air...
>
But if you in the ambient/dry scene .. or if you use your ambient/wet
sub in combination with a scuba-rebreather !-)
Carsten
> Stan
>
> In a message dated 11/28/00 8:32:50 PM Eastern Standard Time,
> vulcania@interpac.net writes:
>
> << That's about what I was getting in the NAUTILUS without any life support
> system; after about 45 minutes, it started getting hard to breathe. I
> figure the volume of the pressure hull was about 35 cubic feet (about 991
> liters?), and she displaces about 2225 lbs. about 1011.36 kilos).
>
> So, given these specifications about my submarine hull and life support
> system, do you still think my new 20 cubic foot O2 bottle will last me about
> 37 hours? >>