Air quality for kids

Last updated 2026-05-23 · This page is for general information and is not medical advice.

Children breathe roughly twice as much air per kilogram of body weight as adults, have developing lungs that are more sensitive to oxidative damage, and tend to spend more time outdoors and engaged in intense activity. They're a textbook sensitive group. This page covers the AQI thresholds parents should pay attention to, what schools should be doing (and what to ask if they're not), and the smoke-season playbook for households with kids.

Why kids are more vulnerable than adults

The biology is straightforward:

• Higher minute ventilation per kg. A 30 kg child breathes about 8 L/min at rest vs. 6 L/min for a 70 kg adult — but per kilogram, the kid's ventilation rate is ~2× the adult's. Same outdoor AQI, double the dose-per-mass.
• Developing lungs. Lung development continues into early adulthood. Chronic exposure during childhood is associated with reduced peak lung function in adulthood — an effect that doesn't fully recover.
• More time outdoors, more time at high activity. Most kids spend more time playing outside than the average adult, and the activity is more intense (running, sports). Both multiply the dose.
• Asthma prevalence is higher. ~8% of US children have asthma. AQI matters more for them specifically. See our asthma page.

Action thresholds for kids

The EPA puts children in the sensitive-groups category, but practical parent-facing thresholds run a bit tighter:

• Green (0–50) — Normal play, sports, anything. No action.
• Yellow (51–100) — Awareness. Note dominant pollutant. Sensitive kids (asthma, recent respiratory illness) reduce sustained outdoor exertion.
• Orange (101–150) — Healthy kids: shorten outdoor PE and sports practice. Move to less intense activities (walking instead of soccer). Kids with asthma: indoor activities only.
• Red (151–200) — All kids: indoor only. Cancel outdoor recess. Move sports practices indoors.
• Purple+ (201+) — Stay home. School closure justified for outdoor-heavy schools.

What schools should be doing

School districts in air-quality-prone regions (California, Oregon, Washington, Mountain West) have written outdoor-activity policies tied to AQI. The general structure that works:

• Yellow (51–100) — Outdoor activities normal; PE teachers monitor sensitive kids.
• Orange (101–150) — Shortened outdoor PE; reduced intensity. Indoor option for sensitive students. Recess shortened.
• Red (151+) — All PE and recess indoors. After-school sports practices canceled or moved to indoor venues. Strenuous outdoor activities (cross-country, soccer practice) canceled.
• Purple+ (201+) — School closure considered, especially for schools without HVAC filtration or in mobile classrooms.

If your school doesn't have a written policy, a polite email asking what they do during smoke events almost always produces one. The CDPH, ORDeQ, WADoH, and EPA all publish reference policies districts can adopt.

The smoke-season playbook

For households in fire-prone regions, the pre-season checklist:

1. HEPA in the kids' bedrooms. The bedroom is where 8+ hours of dose accumulates. A purifier sized per our air-purifier-sizing guide running on its lowest acceptable setting overnight is the single highest-leverage move.
2. MERV-13 HVAC filter. Replace before fire season; change twice as often during active smoke days.
3. N95s in kids' sizes. 3M, Project N95, and Honeywell make N95s in small/medium that fit kids 8+. Toddlers can't fit a respirator effectively — the answer for that age group is indoor sheltering, not masking.
4. Pediatrician contact info ready. Asthma rescue refills, sick visits during smoke events.
5. Activity plan. Pre-decide what indoor activities work during a multi-day smoke event. Bored kids stuck inside is a real management problem; planning beats improvising.

Pollen + AQI vs respiratory illness

Parents often conflate three different exposures that produce similar symptoms in kids:

• High pollen days — sneezing, runny nose, watery eyes. Pollen isn't in the AQI; check local pollen counts separately. Antihistamines help.
• Bad-AQI days — cough, throat irritation, asthma flare. AQI app + HEPA + indoor sheltering helps. Antihistamines don't.
• Respiratory illness — flu, RSV, COVID. Different symptoms (fever, body aches), different management. See AQI and outbreaks for the overlap during smoke + flu season.

Tools that pair with this

Smog Report shows the AQI for your nearest EPA monitor with widget + Lock Screen alerts — useful for the morning "is it safe to walk the dog before school" check. Free on iOS.

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