DIY air pollution sensors

Niall Marsay 
Cranfield University
n.h.marsay@cranfield.ac.uk
ECG Bulletin January 2023

Find out where the air pollution is hiding in your house with this simple DIY sensor. We all live with air pollution daily, but did you know that research suggests there is 2 to 5 times more air pollution inside our homes than outdoors? Air pollution has been linked to higher chances of asthma and allergy and, in some cases, premature death. As environmental scientists, we work to understand where air pollution is and its sources.
This How To shows you how to make a simple though effective air pollution sensor at home to monitor your environment. 

Challenge
Dose the position of the sensors in each room make a difference? Can you think of or find any ways to reduce air pollution in your homes? 
You’ll need
• Paper/ card
• Sellotape
• Scissors
• A hole punch
• Magnifying glass or microscope 

 

Instructions
1. Hole punch the top of the paper.
2. Fold the paper and cut a triangle in the fold. 3. Unfold and place Sellotape over the large hole be carful not to let the Sellotape in the opening touch any surfaces and become “contaminated”.
4. Thread string through the hole to make a hanger. 5. Place a sensor in several rooms in the house and think about which room might have the most air pollution. Do not forget to label your sensors!
6. After a week, take down the sensors and examine them with a magnifier of some sort.
7. What did you find?

​Extension
If you are feeling particularly scientific, try to count the number of particles on each sensor, and estimate the particle density (e.g. how many per square cm). You can then compare quantitatively as well as qualitatively between sensors.