Is there a Do-It-Yourself method for testing air for Volatile Organic Chemicals?
For those who wish to go beyond the “smell” test, scientific testing for volatile organic chemicals can provide an informed basis for embarking on an air purification project, and can satisfy one’s curiosity.
Gas detection technology seems to have developed in approximately the 1980s, in response to awareness of indoor air pollution. Just as different mechanical air filters were developed to deal with different types of particulate or gaseous pollutants, so were gas sensors developed for each type of pollutant. For a summary of how one company tests for the various indoor air pollutants, mainly with gas monitors, see this website.
We looked at Do-It-Yourself mass spectrometers and gas chromatographs, but found none that tested for formaldehyde, benzene, toluene, or xylene, identified in Wolverton’s work as VOCs to be eliminated.
A few types of air testing kits are available for testing air samples, but the tests generally were one-test solutions which were expensive, starting at approximately $40. Some current tests involve exposure of a chemically infused paper that turns color when exposed to the gas. Some involve sending a special vial filled with air to a lab for testing.
In learning that a reasonably-priced, repetitive-use, gas identification method was not easy to come by, we looked for, and finally found, a method that allows for repeated testing, though it involves time, some equipment, and self-teaching. It has the appeal of allowing for creativity and using open-source programming, and potentially connecting to a community of do-it-yourself amateur scientists.
However, this method does require an interest in detail and in electronics, and does require an expenditure of cash, so some may prefer to bypass testing and expend funds for an electronic air purifier which purifies for VOCs.
It should be remembered that there are drawbacks to using plants to purify air, such as maintenance, and a large number of plants if the fan-assisted technology is not used. Many will prefer to filter the air mechanically, which may appear practical and easier than dealing with plants.
But for those who appreciate the value of plant air purification, and will be pleased to involve themselves in do-it-yourself gas testing, here is our lowest-cost DIY solution.
Use an Arduino controller and MQ gas sensor to test for VOCs.
One way to develop a VOC detection system is to use a programmable controller such as the Arduino, along with a message-queuing (MQ) gas sensor for each group of gases to be detected.
In the next two pages, we will review the following components of a do-it-yourself gas detection system:
1. How to attach an MQ-138 gas sensor to an Arduino controller
2. What are the components of the Arduino controller
Click next page to see a video of how an Arduino controller is set up to measure gas with a gas sensor.
