Holidays and gatherings produce multi-source events the dashboard sees as distinct from any single-source pattern. Thanksgiving cooking is hours of gas-stove or oven use plus a roasting turkey (significant fat aerosol, sustained PM2.5 elevation) plus often several lit candles or a fireplace, plus 8 to 20 additional people, plus pre-meal cleaning. The AI recognizes the compound signature and tags it as a gathering event rather than alarming on each component.
CO2 tracks guest count almost linearly. A typical kitchen+living area that holds 600 ppm with the resident family at dinner climbs to 1,200 to 1,800 ppm with twelve people for several hours. The interpretation does not flag this as a ventilation crisis (it is the largest single-day deviation in a typical year); it tracks the recovery time after guests leave.
PM2.5 and VOC interact during gatherings. Multiple candles plus a few hours of cooking plus fragrance from guests can sustain VOC index 200+ and PM2.5 30-80 µg/m³ for the duration of the event. Wood-burning fireplaces add another order of magnitude. These are short-duration exposures; the cumulative-exposure regime is unchanged. For sensitive household members (asthma, cardiovascular), the dashboard suggests proactive HEPA filtration in the room they retreat to, and a post-event ventilation plan.
Recovery is the diagnostic phase. A well-ventilated home returns to baseline within 1-3 hours of guests leaving. A sealed home takes 6-12 hours. If recovery is meaningfully slower than that, the structural ventilation is worth checking before the next gathering. The dashboard's post-gathering analysis surfaces the recovery curve and flags any parameters that did not return to baseline overnight.
