Indoor Mold Growth & Spore Dispersal Simulator (2D)

A damp wall corner is modeled as a grid of cells, each tracking its own Mold Growth Index using a temperature-dependent critical-humidity model from building science: above the local threshold, colonies expand; below it, they slowly dry out and decline. Colonies past a visibility threshold emit spores into a well-mixed room-air model, whose concentration is set by the balance between emission, ventilation air-changes-per-hour, and optional HEPA filtration. Adjust humidity, temperature, ventilation and filtration and watch the wall colonies and the airborne spore cloud respond in real time, with live readouts for the growth index, spore concentration, wall coverage and elapsed simulated time.