Oxygen guage?

[NipplesTheCat]

How do I know how much oxygen I have left in the boat? Is it related to the Co2 levels or is there another gauge I am missing somewhere?

[Herr Russ]

Edit: Just thought about it... I think 3rd. guage is compressed air & not O2... Sorry...

If you click on the Chief Engineer & then click on reports, you'll see the battery, O2 and CO2 guages...

Good Luck..

[SteamWake]

How do I know how much oxygen I have left in the boat? Is it related to the Co2 levels or is there another gauge I am missing somewhere?

Directly related to the Co2 gauge.

As oxygen is used up it is replaced by Co2 more or less at a 1 to 1 basis.

100% Co2 = 0% Oxygen.

[NipplesTheCat]

thanks :D

[Respenus]

But as some people pointed before, a 1 on 1 ration is not realistic. There was a long thread on this matter not long before.

[irish1958]

It doesn't make any difference what the O2 level is; if the CO2 level is high enough, it's toxic.
I have always wondered: why can't the sub exhaust the stale air with the compressed air?

[Jusa_Finn]

I remember reading long time ago that compressed O2 was released inside the sub while being forced to be submerged a long time. It was painful to the crew because the atmospheric pressure increased inside the sub.

I think WWII subs didn't have the technology to exhaust air while submerged.

[Arnold]

Potash cartriges absorb carbon dioxide exhaled to prevent the carbon dioxide level to exceed 4%. Any higher level is dangerous. Does each mark on the CO2 guage (in the stock SHIII sim) equal 4.16% since 100% is 24 equal marks?

[K-61]

Agreed, carbon dioxide levels are the limiting factor. Nobody suffocates from lack of oxygen in confined spaces, they suffocate from carbon dioxide poisoning. Cartridges can stretch the air supply, but eventually the CO2 builds to a toxic level. As for compressed air in the sub, the level of pressure constantly rose due to air leaking from the various lines and fittings in the boat. It was virtually impossible to leakproof subs in WW2; I'm not even certain today's subs have eliminated the problem, but I suspect they have, since modern nuclear subs can cruise submerged for months.

[Gargamel]

I have always wondered: why can't the sub exhaust the stale air with the compressed air?

Because then you'd be compressing the air inside the sub, requiring decompression stops before you could surface.

For every 33ft (so call it 10 meters?) of depth, 1 atmosphere of pressure (14 psi) is added to the pressure outside the hull. In order to vent the bad air with the good air, you'd have to make the pressure inside the hull greater than the outside pressure. at 100m, that's 10 atm of pressure. At that pressure, gaseous nitrogen liquefies into the bloodstream and lodges in various locations in your bodies, primarily the joints, lung and brain tissue.

The pressure would have to be very slowly bled off to allow the crew back onto the surface. If you were at 150m, and vented the air, and then had to surface, You couldn't just pop the hatch. The rapid depressurization would cause every body to rapidly, and very painfully, die.

US Navy dive charts for recreational divers (and I'm doing this from memory), state that at about 110ft (30m +/-). humans have about 5 minutes of bottom time before they are required to make decompression stops on their ascent back to the surface. I am not familiar with deco charts so I cannot speak for times, but Google should present you with some answers on that one. But if at 110 ft, you have 5 min max, imagine how long it would take to deco from a 450 ft (150m) dive for 10 hours. In comparison, at 10m, humans can stay something like 120 minutes, just shows the logarithmic scale of the chart.

Also, rapid pressurization can cause Nitrogen narcosis. Imagine going from sober to 10 beers in 5 seconds. That's what it feels like, been there done that. Some people do it for fun, but a whole crew full of instantly drunk guys is a bad idea IMO.

They could (in theory) slowly add some air to the sub, forcing to CO2 to a lower level closer to the floor, allowing the crew to breathe better when standing. But they could only do a little of this, for reasons I outlined above.

Maybe having some sort of pump force the air out, while slowly letting good air in would work, but any discrepancy in pressures would cause great discomfort to the crew, possibly death.