Air Quality Travel Guide: How to Check AQI Before Any Trip
Air pollution affects 9 out of 10 people worldwide — and many of the world's most popular travel destinations have serious air quality issues for at least part of the year. This guide tells you exactly how to check AQI before your trip, which apps to use, what masks actually work, and the best and worst months to visit 12 major destinations.
Understanding the AQI Scale
AQI values above are based on the US EPA standard (most widely used globally). Some countries use different scales — China's AQI and India's AQI use slightly different breakpoints. Always confirm which standard an app is using.
Air Quality Calendar: 12 Popular Destinations
Delhi (India)
Travel tip: November–January can exceed AQI 300. N95 is essential. Book accommodation with air purifiers.
Bangkok (Thailand)
Travel tip: Chiang Mai in March is far worse than Bangkok. Bangkok's worst is Feb–April (dry + traffic + crop burning upwind).
Beijing (China)
Travel tip: Summer 2024 saw significant improvement. Winter remains challenging. Buy a KN95/N95 in advance.
Jakarta (Indonesia)
Travel tip: Counter-intuitive: Jakarta is WORSE in summer (dry season) due to no rainfall to clean air.
Tokyo (Japan)
Travel tip: Generally safe. March–April kosa (Asian dust) season: monitor JMA forecast if sensitive.
Hanoi (Vietnam)
Travel tip: Hanoi's winter is surprisingly polluted for a tropical city. Bring a mask for Oct–March visits.
Cairo (Egypt)
Travel tip: Year-round sand dust adds to traffic pollution. Summer is ironically the least bad. Mask advised year-round.
Kuala Lumpur (Malaysia)
Travel tip: Haze season (Aug–Oct) is unpredictable — peatland fires in Sumatra/Borneo drive extreme spikes.
Seoul (South Korea)
Travel tip: Spring hwangsa (yellow dust) from China is the primary risk. Check Korea Meteorological Administration forecast.
London (UK)
Travel tip: Generally good. Jan/Feb can have NO2 episodes in central areas. No mask needed for most visitors.
Singapore (Singapore)
Travel tip: Aug–Sep haze from Indonesia can be severe (PSI 200+). Check NEA's 24-hr PSI forecast.
Los Angeles (USA)
Travel tip: Wildfire season (Sep–Nov) can spike AQI dramatically. Check AirNow.gov before any outdoor activity.
Best Air Quality Apps for Travelers
IQAir AirVisual
Best global coverage, excellent historical data, forecasting. Most trusted by health professionals.
Free tier limited. Some regions have sparse sensor density.
AirNow
Official US EPA data. Wildfire smoke forecasts. Very reliable during fire events.
USA only.
Plume Labs Flow
Personal sensor integration. Good European data. Exposure tracking.
Personal sensor expensive. Free tier is basic.
AQICN (waqi.me)
Aggregates official government monitoring data from 130+ countries. Very accurate for covered cities.
Only shows official stations — misses local hotspots. Less polished UI.
Soramame
Japan's Ministry of Environment official network. 1,900 stations. Most accurate for Japan.
Japanese language primary. Web-only.
NEA (Singapore)
Official. Shows PSI (Pollutant Standards Index) used in Singapore alongside AQI.
Singapore only.
Masks: What Actually Protects Against PM2.5
Not all masks are equal. The key factor is filtration efficiency at 0.3 micron particle size — the hardest size to filter (PM2.5 ranges from 0.1 to 2.5 microns).
N95 (USA Standard)
US NIOSH-approved. Look for '3M 8210', 'Moldex 2200', or similar brand + NIOSH TC number. Effective against PM2.5.
KF94 (Korea Standard)
Korean-certified. Boat/beak shape provides better face fit than flat-fold N95. Popular in Asia. LG Airwasher, Bluna are reputable brands.
KN95 (China Standard)
Similar to N95 standard. Quality varies widely by manufacturer. Counterfeits common. Look for reputable brands with GB2626-2019 certification.
FFP2 (EU Standard)
European equivalent of N95/KF94. Required on many EU public transit systems during COVID. Easy to find in European pharmacies.
Surgical/Cloth Mask
NOT sufficient for PM2.5 protection. Surgical masks don't seal against the face — particles bypass around the edges. Only marginally better than nothing.
Fit is more important than filtration rating
An N95 with a poor face seal offers less protection than a properly fitted KF94. The boat-shaped KF94 tends to fit better for most face shapes due to its 3D structure. Perform a seal check: cup your hands over the mask and exhale sharply — you should feel air escaping from the seal if it's not fitted correctly. Adjust the nose wire and ear loops until you get a complete seal.
Practical Tips for Traveling in Polluted Cities
Check AQI 3 days in advance
Apps like IQAir provide 3–5 day forecasts. If arriving during a predicted haze event, pack masks and book a hotel with in-room air purifiers.
Avoid early morning outdoor exercise
Overnight inversions trap pollution near ground level. In cities like Delhi and Bangkok, 6–8am often has the worst air of the day. Wait until 10am+ after sea/land breeze activates.
Choose higher floors in hotels
PM2.5 concentrations decrease with altitude, especially below the inversion layer. Floors 15+ are noticeably cleaner than ground level in highly polluted cities.
Request a room with a HEPA purifier
Many international hotels provide portable HEPA purifiers on request. Carry a portable purifier for extended stays. Hotel choice matters — some high-end hotels have central air filtration.
Avoid outdoor eating on bad AQI days
Roadside food stalls and outdoor restaurants concentrate both kitchen smoke and traffic exhaust. AQI 150+ days: prefer indoor, ventilated spaces for meals.
Taxi vs walking: both expose you
Car interiors don't filter outdoor air unless the cabin filter is fresh. Walking or cycling in heavy traffic gives brief but intense exposure to exhaust. Use a mask for both during bad AQI periods.