A single sensor's alarm logic only tells half the story of a real life-support monitoring network: the other half is where the sensors physically sit relative to a leak. This 3D simulator places twelve gas sensor nodes in a fixed grid throughout a cabin volume and lets you trigger a leak plume that diffuses outward from a random point. Every node reads the local plume concentration plus its own noise and runs an identical threshold + sustained-duration alarm rule, but because the plume has to travel through space, nodes near the leak trip first and distant ones may miss it entirely if it dilutes below threshold before arriving. Tune sensor noise, alarm threshold and sustained duration and watch which nodes catch a leak — and which don't.