Life-Support Standards Compliance Envelope (2D)

Standards In Effect

NASA-STD-3001CO2≤0.53kPa ESA ECSS-E-ST-34CO2≤1.01kPa ISS MultilateralCO2≤1.33kPa

Crew & Hardware

Crew size 4

CO2 scrubber efficiency 70%

O2 generator output 60%

Cabin leak rate 0%

Cabin Readout

Compliant with all selected standards

pCO2

0.30 kPa

pO2

21.0 kPa

Total pressure

101.3 kPa

Mission time

0.0 d

How it works

The cabin's three partial pressures evolve from a first-order mass-balance model, integrated every frame:

dpCO2/dt = k_meta·N − k_scrub·eff·pCO2 − leak·pCO2
dpO2/dt  = k_gen·rate − k_resp·N − leak·pO2
dpN2/dt  = −leak·pN2
P = pO2 + pCO2 + pN2

Crew metabolism (N crew) constantly produces CO2 and consumes O2; the scrubber removes CO2 at a rate proportional to its own concentration, the O2 generator adds O2 at a rate set by its throttle, and any cabin leak bleeds all three gases toward vacuum together.

NASA-STD-3001, ESA's ECSS series and the ISS Multilateral operating limits don't agree on the numbers — each gauge below shows the enabled standards' allowable band for that one parameter as stacked colored zones, with the white outline marking the harmonized band: the intersection every enabled standard must satisfy at once. The marker on each gauge turns red the instant that parameter alone leaves its harmonized band, and the strip at the bottom scrolls a green/red history of the overall compliance state.

Limits shown are simplified, order-of-magnitude representative values based on publicly documented differences between agency life-support standards — not a substitute for the actual regulatory text.

NASA-STD-3001 ESA ECSS ISS Multilateral Harmonized band

Life-Support Standards Compliance Envelope — 2D Gauge & Timeline View