Chemicals (TVOCs)

And their effect on learning environments

Chemicals (TVOCs)

Beyond the impact on wellbeing, research confirms that airborne pollution significantly damages learners’ academic progress.
Volatile Organic Compounds, otherwise known as VOCs are a diverse group of common chemicals that are often found in the air in our homes and offices. They are both naturally occurring and human-made. The Learnometer will detect between  0 and 60,000ppb ±10%

“According to the EPA, “Studies from the United States and Europe show that persons in industrialized nations spend more than 90 percent of their time indoors. For infants, the elderly, persons with chronic diseases, and most urban residents of any age, the proportion is probably higher. In addition, the concentrations of many pollutants indoors exceed those outdoors.”  Because VOCs are such a common and prevalent indoor pollutant, exposure to them can have a variety of impacts on health and comfort. VOCs can contribute to a host of symptoms including headache, fatigue, eczema, and even cancer.

Exposure to moderate levels of VOCs can trigger allergies and asthma. They can cause nasal congestion, cough, wheezing, and pharyngtis (inflammation and soreness of the throat). Aside from respiratory symptoms, VOCs can cause headaches, dizziness, conjunctival irritation (irritation of the membrane covering the eyes and inside of the eyelids), allergic skin reactions, and fatigue.

Higher levels of VOCs can include irritation of eyes and nasal passages, nausea and headaches, lethargy and malaise, rash, skin irritation, and eczema.

Long term VOC exposure effects also contribute to overworking the liver and kidneys and has been linked to cognitive impairment, personality changes, and  cancer.

Which of these many effects specifically impact most on Learning is less clear but two recent studies, one from China one from California suggest that the impact is significant, so we have increased the pollution monitoring power of our final Learnometers.

A 2018 paper in the journal Proceedings of the National Academy of Sciences (, analysed language and arithmetic tests conducted on 20,000 people across China nation between 2010 and 2014. For high pollution levels there were significant drops in test scores in language and arithmetic, with the average impact equivalent to having lost a full year of the person’s education.

Just north of Los Angeles, in 2015, a substantial gas leak impacted on many schools. To reduce the impact simple air purifiers were fitted to schools within a  five mile radius. The gas was long gone by then, but there appeared to be tangible improvements in literacy and maths scores. There is some debate about magnitudes, but a 2020 working paper ( suggests that the impact is similar to a substantial reduction in class size.

In short, pollution hurts learning, even if we are not very clear about how that happens.”

Stephen Heppell

Learnometer Inventor