Asthma triggers: the indoor list

Roughly 25 million Americans have asthma. The disease is multifactorial, genetic susceptibility, viral infections, allergic sensitization, but symptom severity is overwhelmingly driven by environmental triggers, most of which are indoors. EPA's trigger list is the canonical reference.

The big indoor triggers, in rough order of prevalence in temperate-climate North America: dust-mite allergen, mold and dampness, pet dander (especially cat), cockroach allergen (urban areas, multi-family housing), gas-stove NO_x, secondhand smoke, fragrance and cleaning-product VOCs, fine particulates (cooking, candles, wildfire), and cold-dry air in winter. GINA ranks these globally.

For Terrestream, the actionable subset is anything the sensors can see directly or infer: PM_2.5 and PM₁₀ events, NO_x spikes from cooking, VOC bursts from cleaning, mold-risk RH conditions, and outdoor pollen/ozone cross-references. The dashboard's "Asthma in household" setting changes notification thresholds, NO_x notifications trigger at lower levels, sustained humidity gets flagged sooner, and the IAQ composite weights gas and particle parameters more heavily.

For active management, beyond the air itself: an asthma action plan with your physician, allergen-impermeable bedding covers, weekly hot-water laundering, HEPA filtration in the bedroom, and stove ventilation are the highest-yield interventions across most US/Canadian housing. NIH NIEHS publishes evidence-based reviews for clinicians and patients.

This is environmental information, not medical advice. The dashboard's readings help you make decisions about the air in your space. They do not diagnose conditions, interpret symptoms, or replace conversations with your physician. If symptoms persist, worsen, or coincide with a known exposure, talk to a healthcare professional. See the AI's medical-advice scope.