How unhealthy is the air out right now? You do not need your own sensor to find out. Here̵7;s how to find out how bad smoke and pollution are in your local area – or elsewhere.
Understanding Air Quality Index (AQI)
These services show all air quality index numbers. The higher the number, the more pollutants in the air right now.
Note that different countries use different air quality index systems. If you are not in the United States, you need to look up your country’s air quality index standard.
Here’s what the numbers mean in the US:
Timely reports to the audience: PurpleAir
Although there are a number of ways to get official numbers from standardized state sensors – and we will explain them a bit – there is a way to get faster results.
PurpleAir displays more localized air quality numbers. They are much more current but come from people from sensors set up by individuals. Individual sensors in an area may not be positioned correctly. But if you look at an area with several sensors, the average shows you a fairly complete picture.
Just go to the PurpleAir map and search for your local area (or any other area you want information about.)
If a particular sensor is too high or low compared to its ambient, you should ignore it. That said, the sensors in your area should point to an average reading that is fairly accurate right now. They can even suggest differences from neighborhood to neighborhood in your city.
PurpleAir sensors display US AQI numbers even when in other countries, so you can look around the world and compare readings across multiple countries, if you like.
Slower official numbers: AirNow and Smartphone apps
You can also check the official figures reported by your government. In the United States, these figures are provided by the EPA and its partners. They are updated every hour and come from a smaller number of more accurate sensors.
It’s convenient, but they will not show you the most detailed details about air quality if it changes quickly or how air quality differs from neighborhood to neighborhood in your city.
To find these numbers in the US, Canada and Mexico, you can use the AirNow website. Connect a place and you will see the air quality in your area. (For other countries, you will need to find a website with data for your country.)
AirNow also offers a map showing air quality over North America.
For convenience, you can quickly find these numbers via smartphone apps. On your iPhone, both the Maps and Weather apps display air quality information. You can see your local air quality information or see another area on the map and see its local air quality. (This is not available in all countries.)
On Android, you can ask Google Assistant about the air quality of your local area or another area. (Again, Google Assistant does not support this in all countries.) You can also install a third-party app that displays this information.
Both Apple’s and Google’s apps display the same official information that you find on AirNow and on government websites. For information from the audience, contact PurpleAir.
RELATED: How to check your local air quality index on iPhone or iPad
If you want to learn more, Wired did a great job of explaining the difference between the numbers on PurpleAir and AirNow and how they are measured.
The figures generated by the government are the canonical historical, official data for an area – but with conditions changing rapidly and varying from place to place even within a particular city, PurpleAir’s figures may be more useful at the moment.