US AQI guide
AQI 301–500: Hazardous
Health warning of emergency conditions: everyone is more likely to be affected.
Who is at risk
Everyone, including healthy adults.
What to do at AQI 301–500
Walking and commuting
AvoidStay indoors. Postpone non-essential trips.
Running and jogging
AvoidSkip strenuous exercise, even indoors if the air inside is not filtered.
Cycling
AvoidAvoid riding outdoors.
Children playing outside
AvoidKeep children indoors in a room with filtered air.
Older adults and heart or lung conditions
AvoidStay indoors with filtered air and seek care if symptoms appear.
Open windows
AvoidSeal gaps around doors and windows if you can.
Mask outdoors
EssentialN95 or FFP2 mask essential outdoors.
Air purifier indoors
EssentialRun a HEPA purifier on high in a closed room.
Based on the US EPA Air Quality Guide, applied to the current US AQI category. If you have symptoms, follow your doctor's advice.
At home, school and work
- Stay indoors with windows and doors closed and a purifier on high.
- Wear an N95 or FFP2 mask if you must go out.
- Follow instructions from local authorities, including school or office closures.
- Seek medical help for chest pain, severe breathlessness or palpitations.
On other scales
When PM2.5 drives the reading (above 225 µg/m³), this is Very Poor or Severe on India's NAQI. China's MEE index uses the same breakpoints as the US for its headline number but different pollutant tables, so values are usually lower.
Cities at AQI 301–500 right now
US AQI- Kabupaten Barito SelatanIndonesia500
- Kabupaten Gunung MasIndonesia500
- Kabupaten Kotawaringin TimurIndonesia500
- Kabupaten Murung RayaIndonesia500
- Kabupaten TabalongIndonesia500
- PalangkarayaIndonesia500
- Dibba Al-FujairahUnited Arab Emirates500
- BanjarmasinIndonesia435
- Kabupaten Muaro JambiIndonesia411
- PalembangIndonesia345
- Kabupaten Abab Lematang IlirIndonesia301
Frequently asked questions
Is it safe to run outside at AQI 301?
Skip strenuous exercise, even indoors if the air inside is not filtered.
Can children play outside at AQI 301?
Keep children indoors in a room with filtered air.
Should I wear a mask at AQI 301?
N95 or FFP2 mask essential outdoors.
Who is at risk at AQI 301 to 500?
Everyone, including healthy adults.
What is AQI 301 to 500 on India's scale?
When PM2.5 drives the reading (above 225 µg/m³), this is Very Poor or Severe on India's NAQI.