popped eardrums in spacefarer modules

[darknotezero]

so in my last colony, I had a spacefarer module rocket design where i put a storage bin of oxylite in the corner and let that fill the spacefarer module and also eat any off-gassed CO2. It worked well enough, but I started to see that when my dupes would dock their exosuits, they would suffer from popped eardrums.

With my current colony, i've modified my spacefarer module design to address this, but after digging into the mechanics of popped eardrums with my gf when she asked a question about it, I now find myself confused as to why I was getting popped eardrums in the first place:

• oxylite will stop off-gassing when the off-gassing tile or tile around it hits 1.8k
• Oxygen's default mass per tile is 1.8k before it shifts to the next tile
• Popped Eardrums happens when dupes are in an atmosphere of >4k per tile

So how does the pressure in the spacefarer module get so high if the oxylite will stop off-gassing at around the same capacity that oxygen normally occupies per tile? I know that it's possible for more oxygen to occupy a tile when it's in a 'compressed' situation and/or forced by, say, a high pressure vent, but getting to 4k when the only pressure that's happening comes from off-gassing oxylite feels like it should be an extreme circumstance rather than a normal one, and I was getting PEardrums pretty regularly.

[BakerBob]

When the CO2 is being deleted that tile is being overwritten with an amount of O2. When your dupes are breathing out CO2 rather than overwriting the current O2 tile, it shifts the gasses in the tile to the side making space for the CO2. This creates a loop of CO2 being overwritten and overpressurising all tiles in the capsule. A way around this is to set up a powerless gas filter for the CO2 at the bottom of the module and put the Oxylite storage near the top of the capsule to prevent overwriting

[blakemw]

A dupe breaths out a 1 g tile of CO2. That tile of CO2 covers the Oxylite. The Oxylite, if it's a large stack, can emit a large amount of oxygen each outgassing, like for 10t of Oxylite it should be about 5 kg per outgassing.

What's more, with certain configuration of gases, the CO2 won't be destroyed, instead getting merged into another packet of CO2, then splitting off again, the split off CO2 tile can be at lower pressure, if it's below 1.8 kg the Oxylite can outgas. It can basically go on like this, with the Oxylite outgassing each time the CO2 tile splits, until the pressure gets high enough that both halves of a split CO2 tile are above 1.8 kg. This can require in excess of 5 kg of pressure.

To minimize this use smaller amounts of Oxylite and/or store the Oxylite high in the spacefarer. You can set up a permanent CO2 removal system or just have nothing important in the bottom layer (for example the Rocket Control Station should be at the top) and let the CO2 accumulate and manually pump it out from time to time.

[darknotezero]

aaah that totally makes sense.

the solution that i came up with was a little different:

the only small annoyance/negative about this design is that i need to construct/deconstruct a conveyer loader any time i need to load up more oxylite into the corner.

the positive is that it makes a washroom, barracks, and great hall. plus if i have an efficient oxylite farm, i can load up a gazillion tons of oxylite and then forget about it forever more.

room/gas/automation overlays:

Spoiler

 

[Gurgel]

Reminds me when I found something like 50kg/tile of Oxygen in my spacefarer module and it was beging supplied by a regular vent that cannot do more than 2kg/tile pressure. This mechanic is really not very intuitive. The solution there was to place the vent at the bottom so it deletes the CO2.