An Inside Look at How Air Quality Monitors Work

by Amanda Hawkins

The air we breathe is crucial to our overall health and well-being, yet many of us take it for granted. With pollution levels on the rise around the world, monitoring air quality has become more important than ever. 

As air quality technology improves, air quality monitors are an increasingly popular tool used to measure the air quality around us. So, let’s take a look at how air quality monitors work.

Here, we’ll explore how air quality is measured, the methods for measuring air quality, and how you can install your air quality monitor in your neighborhood.

How is Air Quality Measured? 

Air quality is measured by monitoring the levels of various pollutants that affect the air we breathe. Several methods and instruments are used to measure air quality, including air quality monitors and remote sensing.  

The Air Quality Index (AQI) is a measurement scale used to report the levels of common air pollutants in the air. The AQI provides a standardized way of communicating air quality information to the public that is easy to understand and helps people make informed decisions about their health and activities. 

The AQI measures 5 common air pollutants that can negatively impact human health: 

  • Ground-level Ozone
  • Particulate Matter (PM2.5 and PM10) 
  • Carbon Monoxide (CO) 
  • Sulfur Dioxide 
  • Nitrogen Dioxide 

Typically, the AQI ranges from 0 to 500, with higher values indicating poorer air quality. The AQI scale in the US, for example, has 6 categories.

Each category represents a different level of health concern:  

  1. Good (0-50) 
  2. Moderate (51-100) 
  3. Unhealthy to Sensitive Groups (101-150) 
  4. Unhealthy (151-200) 
  5. Very Unhealthy (201-300) 
  6. Hazardous (301-500) 

When the AQI exceeds 100, people with respiratory or cardiovascular diseases, children, and seniors may experience adverse health effects, such as difficulty breathing, coughing, and wheezing. 

4 Methods for Measuring Air Quality  

Air quality monitors use sensors to detect and measure the levels of pollutants in the air we breathe. There are several types of air quality monitors, each designed to measure different pollutants and parameters. 

  1. Particulate Matter (PM) Monitors, like the PurpleAir’s air quality monitors, use laser light scattering to measure the number and size of particles in the air.  
  2. Gas Monitors use sensors to detect and measure the levels of specific gases in the air. 
  3. Meteorological Stations use sensors to measure parameters such as wind speed, temperature, and humidity.
  4. Satellite Imaging is another method commonly used for measuring air quality. This approach involves using satellites equipped with sensors to observe the intensity of light in specific wavelength ranges on the Earth’s atmosphere, detecting the presence of pollutants.  

Satellite imaging can provide a broad perspective of air quality over large geographical areas, which makes it useful for monitoring air quality on a regional or global scale. Additionally, satellite imaging can track the movement of pollutants across different regions. 

3 Tips on Installing Your Air Quality Monitor  

Have you recently invested in an air quality monitor but need help with how to best install it? Here are some tips to get you started. 

#1 - Location and Placement 

The location is the first thing to consider when installing your air quality monitor. If you only have one air quality monitor, you’ll first want to determine if your goal is to measure indoor or outdoor quality. It may be worth considering getting more than one so you can measure both.  

For indoor air quality monitoring, consider the most important room and the purpose of that specific room to determine the best location. For example, if you monitor air quality in a bedroom, consider placing the sensor near the bed. 

For outdoor air quality monitoring, there are a few factors to consider when it comes to location for installation:  

  • Elevation: You’ll want to mount your sensor at a convenient height. Ensure that it’s off the ground to allow for airflow and that water cannot splash into the sensor. 
  • Household Pollution: To get the best reading for the general area, install the sensor away from sources of household pollution such as furnaces, vents and barbeques.  
  • Sunlight: Direct sunlight can impact the temperature so try to place it in a shaded area. 
  • Foliage: Avoid mounting the sensor near trees or other vegetation, as insects can get into the sensor and impact the readings. 
  • Distance From Connectivity: Finally, be sure to install the sensor where it can maintain its WiFi connection. 

But what if you’re not sure that you have the right one for the job? Well, at PurpleAir, we design our air quality monitors for specific conditions which can impact their placement.

Here is a quick guide to help: 

#2 - Follow Manufacturer Instructions 

There are many different types of air quality monitors, so there may be specific manufacturer instructions to follow when it comes to installation. Make sure to read through these instructions before beginning installation.  

Your monitor also may come with air quality monitor maintenance instructions. This help you know how to keep it clean or how to troubleshoot if it stops working properly. 

#3 - Register to an Air Quality Map

Lastly, registering your monitor on an air quality map is a great way to contribute to your community’s overall understanding of air quality. The data collected can be used in scientific research to improve our understanding of air pollution, inform local government policy and regulations, and even connect to you Smart Home automation tools. 

Additionally, you can access data from other monitors in your area through the air quality map. This data can provide a more comprehensive picture of air quality in your community, helping you make more informed decisions about your health and safety. 

Worried About Your Air Quality? 

Monitor the Particulate Matter levels around the world with our free, real-time PurpleAir Map or join PurpleAir's mission to make air quality data accessible to everyone by investing in an air quality monitor for your home. 

Together, we can be informed and make changes in our daily habits and the community to improve air quality.  

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