Children and school staff spend much of the day sharing indoor air. Indoor air quality is now explicitly a workplace health-and-safety issue: the HSA Code of Practice sets out practical measures for compliance with employers’ legal requirements. Better indoor air quality can reduce exposure to airborne pathogens, indoor and outdoor sources of air pollution, microplastics, pollen and more.
Children are particularly susceptible to the harms of air pollution.
Clean indoor air was always needed. The pandemic has made it more urgent than ever.
BBC report on London’s school air-filter programme, 17 October 2025
The Mayor hopes to expand the programme to all London schools and wants London to be a model for the rest of the UK. The UK COVID-19 Inquiry has recommended the immediate rollout of HEPA filters as a first step towards adequate indoor air quality.
Washington DC Public Schools · Ventilation
Washington DC public schools immediately set about upgrading their ventilation systems in response to COVID-19. In Ireland, very few schools have ventilation systems to upgrade. The Irish government decided against providing HEPA filters as standard. There has been no public health information on why HEPA filters would be a good idea.
Response to us from the Department of Education:
“To date 35 schools have applied for additional funding under the emergency works scheme to assist with ventilation. Of these, 24 have been approved, 2 were incorrectly classified as ventilation-related and assessed separately, 7 were rejected as the application form was not fully completed and 2 are waiting for the schools to revert with further information. None of these applications were for the funding of HEPA filters and contact was made with each of the schools who had applications rejected to advise them how best to proceed.”
Dr Jeffrey Siegel, University of Toronto: improved indoor air quality and ventilation in schools has clear benefits beyond COVID, including reduced absenteeism and asthma impacts and improved cognitive and educational outcomes.Prof Chris Whitty, UK COVID Inquiry: ventilation in public buildings should be taken much more seriously — for COVID, flu, RSV, other infections and indoor air pollution.
Our position: We believe the current Irish approach is increasingly difficult to reconcile with the direction of international public-health guidance and the growing evidence base. WHO Europe recommends good indoor ventilation as part of preventing COVID-19 and Long COVID, while CDC guidance for schools explicitly includes cleaner air and portable air cleaners. We regard a system in which classroom air quality is often unmeasured and filtration is not routine as untenable.
200+London schools receiving high CADR HEPA filters in every classroom. Why not Irish schools?
27–68%lower PM₂.₅ in London City Hall filter research. PM₂.₅ is a problem in rural schools as well.
1,319 ppmmedian occupied classroom CO₂ in a 2025 study. 75% of classrooms spend more than 50% of their time above 1,000 ppm.
2×rate of diagnosed Long COVID after a second documented infection in a large US paediatric study
How we got here
The clean-air campaign timeline
From the start of the pandemic to the campaign for healthier classrooms.
Latest research & news
Latest research, news & developments
Selected studies, reporting and developments on clean indoor air, COVID, Long COVID and children’s health. Links go directly to the original source.
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So where are they?
International direction
Cleaner indoor air is still public-health policy elsewhere.
This is not a return to emergency restrictions. It is the application of lessons learned about airborne transmission and indoor air quality.
CDC · Schools
Cleaner air in schools
CDC school guidance says cleaner air can reduce the likelihood of spreading disease and lists portable air cleaners as an option in spaces with low ventilation.
CDC describes cleaner air as a core prevention strategy and advises organisations, where possible, to aim for five or more air changes per hour of clean air using ventilation, filtration or a combination.
Preventing Long COVID starts with preventing infection
WHO Europe says protection from Long COVID means reducing COVID-19 infection in the first place and includes vaccination/boosters, well-fitted masks and well-ventilated indoor spaces among recommended measures.
The Mayor of London’s £2.7 million School Filters Programme is installing HEPA filters in at least 200 schools, with one filter per classroom where possible, plus air-quality monitoring, maintenance and education. City Hall reports previous research showing PM₂.₅ levels 27–68% lower in classrooms using these filters.
Ireland entered the pandemic with a serious asthma burden
Clean indoor air matters independently of COVID-19. Children are particularly vulnerable to air pollution, and asthma has long been a major child-health issue in Ireland.
Children
Around 1 in 5 Irish children has asthma
The Asthma Society of Ireland says asthma affects around one out of every five children in Ireland.
In 2019, the Asthma Society warned that asthma deaths in Ireland were rising. Contemporary reporting described Ireland as having the fourth-highest prevalence of asthma worldwide.
Ireland lagged other countries on youth asthma mortality
A 2019 report said Ireland had the second-highest asthma death rate among young people in the 14 EU countries studied. Across all 19 international countries in that comparison, Ireland ranked fifth for asthma mortality among 15–19-year-olds.
What WHO Europe is saying about Long COVID and clean air.
WHO/Europe's 2026 myth-busting campaign was created because misconceptions about Long COVID continue to hinder diagnosis, prevention, care and rehabilitation. The campaign combines evidence-based information with patient stories and is intended for the public, health and care workers, families and caregivers.
30 January – 31 March 2026
Eight Long COVID myth-busters
WHO/Europe says more than 36 million people across the WHO European Region may have experienced Long COVID during the first three years of the pandemic, while reduced testing and uneven surveillance after 2022 mean the true cumulative number is likely higher.
Its campaign stresses that Long COVID is real, can be life-changing, affects physical, cognitive and mental health, and remains relevant as new infections continue to occur.
Video assembled by Parents for Clean Air from WHO/Europe's 2026 Long COVID myth-busting campaign materials.
1
Young and fit people can still develop Long COVID.
Age or fitness does not provide complete protection after SARS-CoV-2 infection.
2
Severe acute illness is not required.
Long COVID can follow an infection that was not severe, including in people without a pre-existing condition.
3
It is more than “just being tired”.
Long COVID can be debilitating and affect physical and cognitive functioning.
4
It is not laziness or an excuse.
The condition can substantially affect work, education, daily activity and well-being.
5
Symptoms can continue for months or longer.
Long COVID is not limited to symptoms that persist for only a few weeks.
6
Long COVID is a real health condition.
WHO/Europe rejects the claim that it is simply caused by stress, anxiety or poor mental health.
7
Vaccination reduces Long COVID risk.
WHO/Europe states that COVID-19 vaccines reduce the risk of Long COVID; they do not cause it.
8
Long COVID has not gone away.
New COVID infections still lead to new Long COVID cases.
WHO/Europe on clean air
WHO/Europe has long treated indoor air quality as a health issue, including in schools and other settings for children. Its school-focused indoor-air resources note that children can face higher risks from indoor pollutants and provide evidence-informed measures for public settings such as schools, kindergartens and day-care centres.
“Everybody on the planet has the fundamental right to breathe clean air.”
Dr Hans Henri P. Kluge, WHO Regional Director for Europe
“Clean air is a political choice and a societal responsibility.”
Children face a frustrating lack of answers about Long COVID
WHO/Europe has highlighted the particular difficulties children and families can face when Long COVID affects school, daily life and development, including uncertainty, delayed recognition and gaps in support.
Facebook videos: Facebook share links cannot be reliably embedded on external sites, so these now use direct Facebook links rather than broken players.
WHO Europe campaign material and related videos
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Facebook video
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UNICEF's parenting guidance explains that children can experience Long COVID and provides information on symptoms, recognition and when families should seek medical advice.
Irish measurements show why this deserves attention.
Ventilation and filtration do different jobs. Ventilation dilutes indoor pollutants and removes rebreathed air; particle filtration removes airborne particles but does not remove CO₂.
2025 Irish classroom study
A peer-reviewed study across 17 Irish buildings, including nine schools, found a median occupied classroom CO₂ concentration of 1,319 ppm, compared with 714 ppm in offices. Indoor PM₂.₅ tracked outdoor concentrations strongly, and the WHO 24-hour PM₂.₅ guideline was exceeded on 48% of monitored days.
The Health and Safety Authority’s Code of Practice recommends a CO₂ threshold of 1,000 ppm as an indicator of adequate ventilation, while stressing that it is not an acceptable ceiling and that levels should be reduced as far as practicable. Consistent levels above 1,400 ppm indicate poor ventilation.
Natural ventilation can be limited by temperature, noise, security and outdoor pollution. The Irish study found indoor PM₂.₅ strongly correlated with outdoor levels. A clean-air strategy therefore needs both ventilation and appropriate particle filtration, designed for the room and occupancy.
Children & Long COVID
Repeated infection is not a neutral event.
Most children recover from acute COVID, but some develop substantial post-COVID illness. Recent paediatric evidence strengthens the case for reducing avoidable infections and reinfections.
Communications Medicine · 2025
Quality of life and school functioning
In a Dutch cohort of 106 children aged 8–18 with physician-diagnosed paediatric Long COVID, 84.4% reported impaired overall health-related quality of life. Impairment in school functioning was reported by 80.2%, and outcomes were significantly worse than in a comparison group with other chronic health conditions.
This is a clinical Long COVID cohort and should not be interpreted as the prevalence of Long COVID among all infected children.
An analysis of roughly 407,000 patients across 40 US paediatric hospitals found 904 diagnosed Long COVID cases per million every six months after one documented infection versus 1,884 per million after a second documented infection.
The second infection was also associated with higher risks of several post-COVID conditions.
Preventing infections and reinfections matters for children’s health, their attendance and their ability to participate fully in education. Cleaner air is one of the few measures that protects people passively while normal school life continues.
RTÉ & Irish Media
Irish coverage of Long COVID and clean air
Selected Irish reporting and broadcast material on Long COVID, indoor air quality and the experiences of people affected.
RTÉ News · Long COVID
“Devastating impact” on a Dublin family
RTÉ News reported on a Dublin mother whose daughter and son developed Long COVID, including the effects on schooling, daily life and family life.
Cleaner air can reduce exposure to airborne respiratory particles, outdoor particulate pollution that enters buildings, indoor particle sources and pollen. Better ventilation and filtration can also help create more comfortable and functional learning spaces.
Respiratory infection
Cleaner air lowers the concentration of airborne infectious particles. It complements staying home when ill, vaccination and FFP2 masking.
Air pollution & pollen
HEPA filtration removes fine particles. This matters in classrooms influenced by road traffic, combustion, indoor particle sources or seasonal pollen.
Attendance & learning
Healthy indoor environments should be treated as basic educational infrastructure: something that supports attendance, concentration, comfort and participation.
What We Are Asking
We want high CADR (Clean Air Delivery Rate) HEPA filters to be made standard in every classroom as a first, easily achievable step towards adequate indoor air quality for our children and for teachers.
If it is happening in London, Hertfordshire, Canada, the USA, Australia and elsewhere, why hasn’t it happened in Ireland yet, after €62 million in funding was announced for ventilation upgrades and HEPA filters in December 2021?
Truthful public-health information
We want truthful, up-to-date public-health information about Long COVID and the airborne transmission of COVID-19 and other pathogens, as provided in the US by the CDC and State Health Departments.
Indoor air quality guidance
A public-health information campaign on the HSA Code of Practice on Indoor Air Quality.
The HSE FADA report
A public-health information campaign on the HSE FADA report, released in December 2024, which confirms international evidence that women are at far higher risk of Long COVID, risks increase on reinfection, and many people with Long COVID are not recovering.
COVID and the immune system
Truthful public-health information on the impact COVID-19 can have on the immune system.
A national clean-air programme
A national clean-air programme for schools that treats indoor air as a normal part of health, safety and educational infrastructure, with the end goal of achieving excellent indoor air quality in all schools, childcare settings, healthcare settings and workplaces.
Maintenance, filter replacement and long-term funding.
Vaccine and antiviral access
Vaccine access for all, as in the US, including access to Novavax. Antiviral access.
Better antigen-testing advice
Proper advice on antigen testing and why antigen tests are an important tool in reducing transmission and for accessing antivirals, as in the US.
Honesty and accountability
Honesty and accountability from the institutions responsible for public health, education and workplace safety.
Questions for schools
What CO₂ levels are you seeing?
Do you use portable filtration?
What practical barriers are you facing?
What support would make clean indoor air achievable?
London school filtration announcementIrish school filtration examplePublic-health information on post-COVID effectsLong COVID information for childrenUS public-health Long COVID communicationCDC cleaner-air communication
Contact
Contact Parents for Clean Air
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