While building efficiency matters, air quality is vital and poorly ventilated schools remain a nationwide problem, says Steve Keogh, an air technology specialist at Plasma Clean

A recent article in The Guardian estimated that 3.4 million children across the UK are at risk of long-term health conditions and infectious diseases due to poorly ventilated schools. Children spend a large portion of their lives in school – equating to around 7,800 hours across their educational life. We all generate CO2 when breathing out, and when you combine multiple bodies in an enclosed classroom with increased temperatures and humidity, this can significantly reduce air quality.

It is known that a CO2 level above 1,000 ppm has a negative impact. Studies have shown this can cause pupil performance to decrease by up to 15 per cent, cognitive performance to worsen by 60 per cent and could even lead to a significant (30 per cent) increase in headaches and respiratory issues. According to a February 2019 report, also in The Guardian, CO2 levels in schools can regularly exceed 2,500 ppm, causing children to lose focus and even feel drowsy during the school day. 

There are some 32,000 schools of all ages and sizes across the UK and indoor air quality is a challenge for many – most specifically older buildings without good mechanical ventilation. However, even newer school buildings put pupils at risk without proper measures to ensure indoor air quality and ventilation. Many schools believe opening a window is a free and sufficient way of generating a fresh air supply, but it isn’t a practical long-term solution. During the winter months, open windows cause discomfort and significant increases in heating bills.

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Schools in some busy urban areas have particular problems regulating ventilation and ensuring fresh air

There’s also the very real issue of external pollution, such as vehicle emissions. This is particularly the case for schools located in urban areas. Areas of London, Maidstone, Leeds and Doncaster are among the worst affected for unsafe air quality, with at least 3,250 schools in these areas considered at heightened risk. There are regulations in place to ensure that school buildings currently being built or planned for the future adhere to strict guidelines around ventilation. However, existing schools are not expected to meet the same exacting standard.


The solution lies in further investment and tighter guidelines for schools to ensure the protection of pupils’ health and wellbeing. Investing in CO2 sensors and air quality technology allows schools to continuously monitor indoor air quality and adapt the ventilation accordingly. Although the government has begun a £25m initiative to supply over 300,000 CO2 monitors free to state-funded facilities, there won’t be enough to cover every classroom. Moving monitors around can lead to inaccurate readings and, for long-term solutions, indoor air quality must be monitored over a sustained period. 

“Improved air quality is shown to increase performance and grades, support better cognitive function and young people’s wellbeing – and it’s a technology that is also proven to limit the potential for a Covid-19 outbreak”

Here at Plasma Clean, we’ve partnered with air monitoring specialist Airthings, to deliver air quality technology to the education sector. This includes nondispersive infrared sensors (NDIR) to monitor indoor air quality (these are recommended by the Chartered Institution of Building Services Engineers). As well as monitoring CO2 levels, they also assess temperature, humidity, radon, VOCs, pressure, light and virus risk – all in real time. 


Once a problem is assessed, a solution needs to be found. We use ultraviolet germicidal irradiation (UVGI). It improves indoor air quality and reduces the risk of airborne infections. It’s a proven technology used by schools for more than 80 years. From the hallway to the classroom, we’ve found it to be effective for both old and new buildings – upper room UVC can provide up to 20 air changes per hour in comparison to mechanical ventilation, which generates only between two and four air changes per hour. 

What matters is the impact: improved air quality is shown to increase performance and grades, support better cognitive function and young people’s wellbeing. In addition, it’s a technology that is proven to limit the potential for a Covid-19 outbreak. All parents have the right to know that their child’s health and education isn’t being negatively impacted by poor air quality. We believe it’s time for the nation’s schools to tackle this issue head on. 

Further reading: Bad made good – how recycled plastic is being put to good use in school settings