Department of Environmental Protection


Air Quality, Energy & Sustainability

Division of Air Quality — Air Monitoring

Community Science Air Monitoring

NJDEP monitors air pollutants throughout New Jersey to protect public health and the environment.

Communities can now also monitor their own air quality, using portable and relatively affordable instruments. These “low-cost sensors” range in price from a few hundred to a few thousand dollars.

Use a low-cost sensor to:

  • Do your own research
  • Learn more about air pollution
  • Find local sources of pollution
  • Monitor hotspots

What’s the Best Approach to Using Low-Cost Sensors?

What Do You Want to Find Out or Show With Your Measurements?
What Do You Want to Find Out or Show With Your Measurements?

Before choosing a project type and low-cost sensor, first identify:

  • The air pollution issue that concerns you
  • The field conditions you are likely to encounter
  • The length of time you should collect data
  • The potential quality of these measurements

Use the information above to develop a question or goal that air monitoring can help to answer.

Here are a few examples:

  1. How can I teach my students about air quality and integrate hands-on data collection into the lesson plan?
  2. What is my exposure to air pollution during my usual walking route?
  3. Are pollutant levels higher near a source in my neighborhood?
What Pollutants Do You Want to Measure?
What Pollutants Do You Want to Measure?

To get the sensor that will fit your needs, you have to decide on a target pollutant, or pollutants. In other words, what should your low-cost sensor be able to measure?

Some pollutants can be found in the air everywhere, such as the ones that NJDEP monitors:

  • Ozone (O3)
  • Particulate matter (PM2.5)
  • Nitrogen dioxide (NO2)
  • Sulfur dioxide (SO2)
  • Carbon monoxide (CO)

These have National Ambient Air Quality Standards that are set at levels to protect human health and the environment.

Other pollutants may not be routinely monitored, and may even be difficult to measure. Some can have local impacts when they are emitted by nearby facilities or mobile sources (cars, buses or trucks).

Learn more about air toxics

Learn more about hazardous air pollutants

What Kinds of Low-Cost Sensors Are Available?

low cost sensorLow-cost sensors range in price from a few hundred to a few thousand dollars, while regulatory monitors like those used by NJDEP can cost tens of thousands of dollars. Some give results in actual concentrations, others use a yes/no light to indicate the presence of a pollutant, others use a color code to indicate whether levels are of concern. The sensor you select should be able to collect data that will answer your questions.


What Kind of Funding Assistance is Available?

Funding is sometimes made available by the U.S. Environmental Protection Agency (USEPA) or other public health agencies for community groups to carry out studies using low-cost sensors. The funding may require partnering with a university or state agency.


  • NJDEP has a limited number of low-cost sensors available for community groups to borrow. Contact the Bureau of Air Monitoring at about the low-cost sensors that are currently available.
  • For an example of how sensors can be used for a classroom project, see the Student Air Monitoring Project

What Do My Sensor Readings Mean & What Are Normal Levels?

The following sources can help you understand different levels of air pollution.

AQI Level Public Health Risk
Air pollution poses little or no risk.
Air quality is acceptable, but may affect people who are unusually sensitive.
Unhealthy for Sensitive Groups
Members of sensitive groups may experience health effects.
Everyone may begin to experience health effects.
Very Unhealthy
Health warning: The entire population is likely to experience health effects.
Health alert: Everyone may experience serious health effects.

What Type of Low-Cost Sensor Project Works for You?

NJDEP has developed technical guidance for four types of low-cost sensor projects.

Read through the four project descriptions pdf before deciding which type of project you’d like to do.

After reading through the project descriptions, use the table below to link to guidance documents that will help you develop and carry out that specific type of project.

Contact the Bureau of Air Monitoring at if you have questions about doing a community science project.

Also see the “Helpful Links” below.

4 Types of Low-Cost Air Sensor Projects

Type Purpose Description Level of Effort
1 General Information and Education pdf Sensors indicate the presence or absence of pollutants, or relative quantities, with indicator lights or color coding. Low
2 Personal Exposure Monitoring
Group pdf
Wearable sensors measure air pollution that individuals are exposed to during their daily routines. Medium-High
3 Supplementary Network Monitoring pdf Sensors are placed in an area where the regulatory network is lacking to better understand air quality in those locations. Medium-High
4 Hotspot Identification and Characterization pdf A cluster of sensors is placed downwind of or around a source to identify its potential air pollution impacts. High