Children can be more affected by air pollution than adults because their lungs and other systems are still developing, they are often active outdoors, and they breathe more air relative to body size. EPA identifies children as an at-risk group for ozone and particle pollution and links exposure with coughing, wheezing, and aggravation of illnesses such as asthma (EPA criteria-air-pollutant indicators for children).
Parents do not need to invent a different “safe AQI” for every sport or age. A better plan combines the official pollutant-specific activity guidance, the child's symptoms and asthma plan, the length and intensity of the activity, and access to cleaner air.
Why Children Need Extra Attention
Children are not simply smaller adults. Their lungs and other organs continue developing, their behavior can increase contact with outdoor pollutants, and active play raises ventilation rate. EPA's assessment of environmental risks also notes that children take in more air relative to their size and body weight than adults (EPA report on climate, air quality, and children's health).
Some children need additional planning, including those with asthma, other lung disease, heart conditions, or a history of symptoms during smoke or ozone events. Risk is not determined by age alone; housing, nearby sources, school facilities, access to healthcare, and the duration of an event can all affect exposure.
Read the AQI Before Making the Decision
The U.S. AQI reports the highest index among the pollutants being measured. The same overall number can be driven by PM2.5 on a smoke day or ozone on a sunny summer day, and the useful controls differ.
- Check the current AQI and forecast at AirNow or your local air agency.
- Identify the main pollutant, not just the color or number.
- Check how long the event is forecast to last and whether conditions are changing.
- Consider the child's planned activity, symptoms, and health plan.
- Recheck before a long practice, field trip, or commute because current readings can change.
AirNow's real-time public data are preliminary and may update after quality checks. Nearby smoke can also vary over short distances. Treat the AQI as a decision aid, not a precise measurement of one child's personal dose.
Use Official School Activity Guidance
EPA and AirNow publish Air Quality and Outdoor Activity Guidance for Schools to help keep children active while reducing exposure. The guidance does not impose one blanket indoor rule at the first sign of pollution. Instead, it progressively adjusts duration and intensity:
- On Good days, normal outdoor activity is appropriate.
- On Moderate days, watch unusually sensitive students for symptoms.
- When air is Unhealthy for Sensitive Groups, short activities such as recess can often continue, while longer activities should include more breaks and lower intensity; students with asthma should follow their action plans.
- When air is Unhealthy, everyone should take more breaks and reduce intensity, and schools should consider moving longer or more intense activities indoors or rescheduling.
- When air is Very Unhealthy, the school guide recommends moving activities indoors or rescheduling.
These are category-level public-health recommendations, not a medical clearance for every child. Local agencies may issue stronger directions during wildfire smoke, extreme heat, a chemical release, or another emergency.
Duration and intensity matter
A brief, low-intensity recess is not the same exposure as a two-hour endurance practice. The AirNow framework emphasizes three adjustable levers:
- make an activity shorter;
- make it less intense; and
- take more breaks in cleaner air.
Moving an activity earlier is useful only when the local forecast indicates cleaner conditions. Ozone often follows a different daily pattern from wildfire PM2.5, so “always exercise in the morning” is not a universal rule.
Build a Family and School Plan
For a child with asthma or another condition
Use a written action plan prepared with the child's healthcare professional. Make sure the school has the current plan, prescribed quick-relief medicine where permitted, emergency contacts, and clear instructions for symptoms. Do not change medication because of a blog post or an AQI number.
Questions for the school or childcare provider
- Which official source supplies current AQI and forecasts?
- Who decides whether recess, PE, or sports are modified?
- Are decisions based on the main pollutant and activity duration?
- Is there a room with effective filtration and safe cooling?
- How are families notified during smoke, heat, or evacuation events?
- How are asthma action plans and prescribed medicines handled?
- Are bus and vehicle engines kept from idling near air intakes and pickup areas?
A school's distance from one road does not by itself determine the child's total exposure. Building ventilation, traffic patterns, nearby sources, time outdoors, indoor sources, and actual monitoring all matter.
Make Indoor Air Cleaner
Keeping a child indoors helps only if the indoor environment is cleaner and safe.
During outdoor PM2.5 or wildfire smoke:
- close windows and select recirculation on HVAC or air conditioning when appropriate;
- use a portable air cleaner with enough tobacco-smoke CADR for the room;
- avoid smoking, vaping, candles, incense, aerosol sprays, and smoky cooking;
- keep the room safely cool; and
- ventilate when outdoor air improves.
Use the air purifier size calculator and our clean air room guide. A purifier reduces particles; it does not remove every gas, correct mold or moisture, or make fuel-burning appliances safe. Maintain working smoke and carbon-monoxide alarms.
If power fails, the home overheats, smoke still enters heavily, or authorities issue an evacuation order, relocate to a suitable cleaner-air/cooling location or follow emergency instructions.
Respirators for Children Require Care
The first choices are cleaner air and less time in smoke. CDC/NIOSH says children age two and older can wear masks or respirators, but NIOSH-approved respirators are generally designed for workplace adults and may not be available in sizes that fit very young children (CDC/NIOSH child fit considerations).
If a child uses a respirator, it should cover the nose and mouth, fit under the chin without impairing vision, remain in place, and be worn according to its instructions. Poor fit, frequent removal, or pulling it below the nose reduces the intended benefit. Never put a mask or respirator on a child under age two or a person who cannot remove it independently.
An N95 filters particles, not ozone, carbon monoxide, or vapors. It also does not make outdoor sports during smoke risk-free.
Watch the Child, Not Only the App
Air pollution can be associated with coughing, wheezing, chest tightness, unusual shortness of breath, eye or throat irritation, or reduced exercise tolerance. If symptoms appear, stop or reduce the activity and move to cleaner air. Follow the child's action plan and prescribed medication instructions. Seek medical help when symptoms do not improve as the plan specifies, and use emergency services for a medical emergency.
Do not assume that a child without diagnosed asthma cannot have symptoms. Conversely, do not diagnose asthma or long-term injury from a single smoke day based on an AQI app.
Do Not Translate a Child's Day Into “Cigarettes Smoked”
Our cigarette-equivalent model is not designed to estimate a child's personal health risk, school safety, inhaled dose, or the effect of a mask. It accepts only a U.S. PM2.5 AQI or a direct PM2.5 concentration. An overall AQI driven by ozone, CO, PM10, sulfur dioxide, or nitrogen dioxide must not be treated as PM2.5.
The Berkeley Earth framework is a population-level risk-communication heuristic based on long-term epidemiology. It is not literal smoking, a pediatric risk equation, or medical advice. Use AirNow's activity guidance—not a cigarette comparison—to make a child's daily activity decision.
A Simple Parent Checklist
- Check current and forecast AQI and identify the pollutant.
- Use the official activity category instead of a homemade cutoff.
- Adjust time, intensity, and breaks before cancelling all movement.
- Follow the child's asthma or disease action plan.
- Coordinate with school or childcare staff.
- Maintain a safely cooled, filtered indoor space.
- Watch symptoms and recheck changing conditions.
- Follow local smoke, heat, fire, and evacuation instructions.
Bottom Line
Protecting children from air pollution is a repeated decision process, not one universal AQI threshold. Use official pollutant-specific guidance, reduce long and intense exposure as conditions worsen, make indoor air genuinely cleaner, and anchor medical decisions in the child's action plan and healthcare team.