Professional Air Purifiers for School Classrooms Environments

February 18, 2021 5 min read

Professional Air Purifiers for School Classrooms Environments


Schools across the UK have closed for a third national lockdown in efforts to reduce increasing rates of Covid-19 transmission and infection. Millions of families have been forced to re-adapt to home learning arrangements again.

While school closure forms an important part of national efforts to curb increasing infections, hospital admissions and mortality rates, we believe that once schools reopen, measures can be taken to provide additional protection from Covid-19 and safe learning environments for children. 

Here we explore the benefits of adopting air filtration and purification systems in school classrooms, alongside currently recommended measures such as social distancing, hand washing and face mask use. These provide protection against Covid-19 and improve indoor air quality more broadly.

Why is air purification in schools important?

Over the course of the pandemic, we have learned more and more about the ways in which Covid-19 is transmitted. In July 2020, the World Health Organization (WHO) highlighted that the virus can be passed on through aerosols, particularly in indoor settings with poor ventilation.[i]

It is vital that schools and other education settings take steps to provide safe learning environments for their pupils once they are able to reopen. This includes taking action to mitigate the risk of Covid-19 transmission and infection in classrooms.

In addition, the Royal College of Physicians (RCP) and Royal College of Paediatrics and Child Health (RCPCH) recently highlighted the need to consider the impact of low indoor air quality in homes and schools on health. Air pollution is linked to increased risk of asthma and allergies, impaired cognition, impaired lung and cardiovascular development, gene changes causing cancer and other disease associated with ageing. Regarding schools, the RCP and RCPCH recommended actions to ensure adequate ventilation and that ventilation systems are regularly maintained, noting that use of high-grade air filters in higher polluting areas may be beneficial.[ii]

The UK Government is hesitant to officially recommend air purification systems for some environments. This is understandable, as the market for air purification is currently unregulated and there are products available which make misleading efficacy claims. Nevertheless, high-quality High Efficacy Particulate Air (HEPA) filters - which are classified according to the EN1822*, certified and guaranteed leakage free - can provide significant protection from airborne viruses and pollutants in the ambient air. 

Protecting children from Covid-19 and general air pollution in schools

Effective air filtration systems which use HEPA filters successfully capture virtually all airborne particulate contamination that goes through its filters. Respiratory viruses and bacteria can effectively be filtered from indoor air using these technologies, including SARS-CoV-2, which measures between 0.25 and 1.0 μm in diameter.[iii]

In addition to removing viruses and bacteria from ambient air, HEPA filters are also effective in reducing traffic pollution, which has been a significant concern when air pollution penetrates into the school buildings, and therefore effect the air in school classrooms.

In 2020, a pilot study was conducted with two schools in South West London. It assessed the impact of installing IQAir high-performance air purifiers in classrooms and found a reduction of up to 96% of particulate pollution compared to outdoor pollution levels. Following the study period, the schools’ owner commented:

“We could immediately see the improvement in air quality throughout the schools, measured and visible in real-time, and with no inconvenience caused within the classes. This has provided reassurance to both the teachers and to parents that their children's respiratory health is being given the best protection through cleaner filtered air when attending our schools.”

The results of a different study conducted with a West London school found that the IQAir system demonstrated a removal effectiveness of up to 88% for both PM10 and PM2.5.

How have other countries utilized air purification systems in schools?

The German Federal Environment Agency published guidance in August 2020 highlighting that the use of consistent ventilation technologies indoors can significantly reduce the risk of Covid-19 transmission, when used in conjunction with general hygiene and distancing advise.[iv]

The Federal Institute for Occupations Safety and Health similarly notes that use of professional air purifiers can be a sensible technical solution to controlling indoor air contamination. Particularly for rooms with high occupancy density and when combined with ventilation measures that supply outdoor air.[v] 

In rooms with high occupancy such as school classrooms, the Agency noted the importance of effective airflow monitoring, alongside targeted placement of appropriate ventilation device, to ensure adequate protection. This can be achieved through monitors such as the IQAir AirVisual Pro air quality monitor, which can indicate where additional ventilation is needed, and in conjunction with the IQAir high-performance air purifier to monitor improvements in indoor air quality.

As a result of this guidance, the German Government has recently invested €500 million to improve ventilation systems in public buildings such as offices, museums, theatres, universities and schools, with funding also available for C02 sensors which indicate when indoor air quality is lacking oxygen.[vi]

This is an important and welcome step in reducing Covid-19 transmission and improving air quality in indoor environments. A step we hope the UK will soon follow, particularly in school environments once they reopen.


The IQAir high-performance air purifiers have been tested according to EN1822 and show an absolute minimum filtration efficiency of 99.5% for any particulate pollution, regardless of size and speed setting the unit is used on. The IQAir high performance air purifiers can be used as an effective supplemental measure to protect against Covid-19 and exposure to indoor air pollutants in schools.

Furthermore, the IQAir AirVisual Pro air quality monitor provides much-needed information to determine when ventilation is required and how to best utilise an professional air purifier.

We believe that together these systems can support schools to provide safe environments for their students and form an important part of the national Covid-19 response by helping to reduce transmission and infection.

*For more information on the EN1822 test, please see our blog article available here [insert link].



[i] World Health Organization. Transmission of SARS-CoV-2: implications for infection prevention precautions. July 2020. Available:

[ii] Royal College of Physicians and Royal College of Paediatrics and Child Health. The inside story: Health effects of indoor air quality on children and young people. January 2020. Available:

[iii] Zhao B et al. Air purifiers: A supplementary measure to remove airborne SARS-CoV02. Building and Environment. June 2020. Available:

[iv] Federal Environment Agency. The risk of transmitting SARS-CoV-2 indoors can be reduced by suitable ventilation measures. August 2020. Available: dokumente/irk_stellungnahme_lueften_sars-cov-2_0.pdf

[v] Federal Institute for Occupational Safety and Health. Ventilation in accordance with infection control - Instructions and measures in times of the SARS-CoV-2 epidemic. September 2020. Available:

[vi] Federal Ministry of Economic Affairs and Energy. To curb the spread of COVID-19: €500m for ventilation equipment in public buildings and places where people meet. October 2020. Available: euro-500-million-for-ventilation-equipment-in-public-buildings-and-places-where-people-meet.html

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