Most of us spend much of our time indoors. The air that we
breathe in our homes and work areas can put us at risk for
health problems. Understanding and controlling some of the
common pollutants can help improve your indoor air quality,
and reduce yours and your family's risk of health concerns
related to air quality.
A DIY
Indoor
Air Quality
Monitoring
System
By Tom Kibalo
There are some excellent guides on this available from the US Environmental Protection Agency, but an important step in this process is to begin to monitor your indoor air environment. Given the availability of inexpensive gas
sensors, gas monitoring for the DIY enthusiast is
readily attainable. As a result, we decided to
build our own gas monitoring prototype system
using ISaAC (a Raspberry Pi adapter board
introduced back in the Nuts & Volts August
2014 issue) and a Raspberry Pi. ISaAC seemed
like a natural fit based upon its ease of use with
the Raspberry Pi — especially in this type of
measurement and control application. We finally
ended up with a monitoring air quality
measurement system capable of collecting,
measuring, and recording selected indoor air gas
pollutant concentrations and the ability to report
pollutant levels in real time, while allowing long
term logging of concentrations to understand
both trends and to facilitate rework/validation
for any notional remedies. The resulting
prototype system is portable enough for easy
deployment to isolated areas of a house
including the basement, garage, bedroom, attic,
etc.
In this article, we will discuss the prototype
system design, our sensor selections, and the
approach we used on how to apply specific
manufacturer’s specifications to derive gas
concentration levels. Let’s get started!
August 2015 53
