It is a sunny morning, the kids want to play in the garden, and you are planning a walk before work. But is it safe to go outside today? The sky looks clear — yet air pollution is often invisible. What you cannot see can still affect your breathing, energy levels, and long-term health.
The good news is that you do not need a science degree to decide. A quick check of the Air Quality Index (AQI) and a few simple rules can tell you whether today is a green-light day or a stay-indoors morning.
Why "looks fine" is not enough
Our eyes are poor pollution detectors. Fine particles (PM2.5), ozone, and nitrogen dioxide can reach unhealthy levels on days that look bright and blue. Winter smog, traffic rush hour, wildfire smoke, and dust storms all push readings up without obvious visual cues.
That is why public health agencies worldwide recommend checking air quality today before outdoor plans — especially if you have asthma, a heart condition, young children, or older adults in your household.
What changes through the day
Air quality is not fixed at breakfast time. Pollution often peaks during morning and evening commutes, dips mid-morning when wind picks up, and can spike again in hot afternoons when ozone forms. Checking once is helpful; checking the hourly forecast is even better.
AQI safe levels — a quick reference
AQI safe levels depend on who you are and what you plan to do outside. Here is a practical guide most people can follow:
0–50 (Good)
Air quality is satisfactory. Go outside freely — walks, sports, and playground time are all fine for most people.
51–100 (Moderate)
Acceptable for the general public. Unusually sensitive people may notice mild effects during long or strenuous activity. If you have mild asthma, keep an inhaler handy.
101–150 (Unhealthy for sensitive groups)
Children, older adults, and people with lung or heart disease should reduce prolonged outdoor exertion. Healthy adults can usually manage light activity but should skip intense workouts.
151+ (Unhealthy and above)
Everyone should limit time outside. At very high levels, stay indoors with windows closed and follow local health advisories.
Who should be extra careful?
Even moderate air quality today can matter more for some groups:
- Children breathe faster than adults and spend more time active outdoors.
- Asthma and COPD sufferers may react to pollution before others notice anything wrong.
- Pregnant people are advised to avoid sustained exposure during high-AQI periods.
- Older adults and those with heart disease face higher risk from fine particles entering the bloodstream.
If anyone in your household falls into these groups, treat AQI above 100 as a reason to shorten outdoor time or move activities indoors.
Practical decisions for common situations
School run and playground
A short walk to school is usually fine below AQI 100. If readings are orange or higher, keep playtime shorter and avoid running games near busy roads.
Exercise and sport
Heavy breathing pulls more pollution deep into the lungs. Postpone vigorous runs and cycling when AQI exceeds 100, or shift to early morning when levels often dip.
Opening windows
Fresh air is wonderful when outdoor pollution is low. When AQI rises, closing windows keeps indoor air cleaner — especially if you live near a motorway or industrial area.
Masks — when they help
Cloth masks do little for fine particles. A well-fitted N95 or KN95 can reduce exposure during smoke events or long waits in traffic, but reducing time outside is still the best strategy.
How to check before you leave
- Open a trusted air quality tracker on your phone or computer.
- Allow location access or search for your city.
- Read the current AQI and the dominant pollutant (often PM2.5).
- Glance at the hourly forecast — is it improving or getting worse?
- Match the reading to the activity you have planned.
This whole process takes less than a minute. Make it part of your morning routine the same way you might check the weather forecast.
Check live AQI on Aether
Aether shows real-time air quality today for cities worldwide — live AQI, PM2.5 levels, hourly forecasts, and health context in one free dashboard. Whether you are in Johannesburg, London, or checking conditions while travelling, you can see if it is safe to go outside today before you step out the door.
See the air quality where you are right now — updated in real time.
Check live AQI on Aether