Re: [PSUBS-MAILIST] pressure hull sizing

[Al Secor <wreckdiver@usadatanet.net>]

This has been covered before in the list archives.  You input O2 at the
rate your body metabolizes it...somewhere between .8 and 1.0 liters per
min at rest.  You circulate the cabin air through a CO2 scrubber which
extracts the CO2 from the air.  As a result there should be no net
increase or decrease in cabin pressure and it remains at 1 atm.  A
simple baramoter can be used to keep track of the cabin air creeping up
or down.  A valve to vent the cabin environment to the outside at the
surface will equalize and small pressure differential to avoid any
difficulties in opening the main hatch.

Al

DBACKIDS@aol.com wrote:
> 
> It seems that whether you put the excess air into a tank, or vent it
> (which seems a better idea), you will still need a pump, because as
> Adam said, the surrounding pressure also increases. A valve would only
> equalize the pressure, would it not?

-- 
Al Secor  ARS: WA3PWX  Scuba Instructor SSI DCSI #5528 TDI #1413
http://www.geocities.com/SubDiverI