Public Lab Wiki documentation

Simple Air Sensor

3 | 31 | | #18517

The Simple Air Sensor is a prototyping and onboarding kit for study design around air sensing.

It is also part of an effort to develop an open source project and community that functions similarly to #PurpleAir, so that, over time, people can transfer the expertise they've developed as #PurpleAir users regarding installation, organizing, communication, etc to an open source ecosystem. In this way, this kit offers an "offramp" from a corporately controlled, closed source project that lacks public forums for asking and answering questions, or for organizing and advocating around the data collected.

NOTE: The colored light displayed by this sensor is not related to the Air Quality Index (AQI) colors in any way.


  • to see immediate qualitative differences in air quality at low cost; by displaying a realtime colored light readout, this kit supports explorations into how the particulate sensor used in the closed source #PurpleAir responds to varying air conditions
  • to build familiarity with the electronic components used in air sensors without having to program
  • to use in groups (with 3+ sensors) to plan out placement of a #PurpleAir or other more expensive sensor, for example with consideration for wind direction and spacing


This project emerged from observations that while many people share an understanding of the importance of "right to know" laws and of the purpose that transparency serves in a society, here is much less awareness of the fragility of technology, and the (inadvertent) gate-keeping role of expertise that leaves people without a pathway to "knowing how they know." This project is part of a longterm effort to encourage a culture of empiricism.

More about what's in the Simple Air Sensor

This sensor circuit uses the same type of particle detector as the #PurpleAir sensor, but only one as compared to #PurpleAir's two; does not include a temperature, humidity and pressure sensor as the Purple Air does; and instead of logging either to the cloud or to the device itself, it displays a red/yellow/green light that illustrates the PM2.5 levels it detects without converting into an Air Quality Index (AQI).

This project is part of an ecosystem

Quite a few people have built simple open source, Arduino-based devices around the cheap #plantower particulate air sensor datasheet, see:

This is a version that is easy to assemble (no soldering, just push wires into a breadboard), and comes pre-programmed. We also offer it assembled and ready to plug in in the Public Lab Store.

Parts List

  1. 1 Arduino
  2. 1 RBG LED Light
  3. 1 Sensor with cable
  4. 1 Breadboard


Add an activity or request an activity guide you don't see listed


Title Author Updated Likes Comments
Brainstorm on ways to use colored light to show sensor readings @warren about 1 year ago 8
What do the different colors mean on the Simple Air Sensor? @stevie about 1 year ago 5
How could we design a group activity around siting air sensors? @warren over 1 year ago 10
What do I do next, after using a low-cost or DIY air sensor? @warren over 1 year ago 7
What happens to the simple air sensor when the battery pack runs low? @stevie over 1 year ago 11
Can someone clarify the colors on the simple air sensor? (turning white when plugged in) @stevie over 1 year ago 5
What are the advantages to using 2 particle sensors at the same time? @warren over 1 year ago 11
What are some activities for using the Simple Air Sensor as part of a broader air quality project? @warren over 1 year ago 15
Is there a predictive relationship between the number of PM 2.5 and smaller airborne particulates compared to the mass of the same ug per cubic meter? @Tomp over 1 year ago 5
Can we log data on an Arduino without an SD card? @warren over 1 year ago 3
Questions about Plantower sensors from the University of Wisconsin - Eau Claire @OrionAllgaier over 1 year ago 5
Show more

Ask a question  or help answer future questions on this topic