Below are several papers (PDFs) published by the UK Government’s Scientific Advisory Committee for Emergencies (SAGE) which relate to ventilation and building services.
Role of Ventilation in Controlling SARS-CoV-2 transmission
Published 23rd October 2020
This was the first SAGE paper looking at the importance of ventilation in reducing viral transmission. It highlighted the risks of higher transmission in poorly ventilated spaces and the need to focus on improving ventilation in those areas rather than increasing rates in better ventilated spaces. It recognised that increased occupation of spaces has a significant impact on transmission, with a doubling of occupancy increasing transmission risk fourfold. It concludes that ventilation should be considered as part of a hierarchy of risk controls approach and that measures to control sources of infection such as restricting or reducing duration of activities and enhanced use of face coverings should be considered alongside ventilation for reducing far-field aerosol transmission risks.
Application of CO2 monitoring as an approach to managing ventilation to mitigate SARS-CoV-2 transmission
Published 11th June 2021
This paper provides an update on earlier guidance on the importance of ventilation to mitigate transmission of COVID-19. It includes recommendations for appropriate ventilation rates and provides baseline carbon dioxide (CO2) concentrations in indoor air that indicate good or poor ventilation. It also considers in more detail the evidence for the physical and behavioural factors that need to be considered to deploy CO2 sensors as a means to identify highly occupied and poorly ventilated spaces or to enable occupants to manage ventilation provision in a space.
Potential application of Air Cleaning devices and personal decontamination to manage transmission of COVID-19
Published 4th November 2020
This paper recognized the potential application of air cleaning devices to reduce airborne transmission risks in poorly ventilated spaces and the limited benefit in spaces that are already adequately ventilated.
Air cleaning devices are no substitute for ventilation and should never be used as a reason to reduce ventilation; all occupied spaces need background ventilation to be suitable for human habitation and to comply with building and workplace regulations. It is better to improve ventilation than install air cleaners. There is some evidence that candidate air cleaning technologies are effective against other coronaviruses, but there is as yet little data to demonstrate effectiveness against SARS-CoV-2. Advice in this paper is therefore based on potential effectiveness drawn from the known efficacy of devices against other viruses and the principles of virus transmission.
Air cleaning devices based on fibrous filtration or germicidal UV (UVC) are likely to be beneficial if deployed correctly and are recommended for settings where the ventilation is poor and it is not possible to improve it by other means. The efficacy and safety of such devices should be evidenced by relevant test data. Other technologies including ionisers, plasma, chemical oxidation, photocatalytic oxidation, electrostatic precipitation have a limited evidence base for effectiveness against SARS-CoV-2. They could potentially generate undesirable secondary chemical products that could lead to health effects such as respiratory or skin irritation. These devices are not recommended unless their safety and efficacy can be unequivocally and scientifically demonstrated by relevant test data.
Application of UV disinfection, visible light, local air filtration and fumigation technologies to microbial control
Published 31 July 2020
This paper summarises the evidence for the use of ultraviolet (UV) disinfection, visible light, local air filtration and fumigation technologies to control COVID-19 transmission. It provides a detailed review of the knowledge of these technologies up to May 2020.
MHCLG Housing Impacts Paper
Published 10th September 2020
This paper was written in response to an MHCLG request for advice from SAGE to better understand the role of housing in transmission and how it might be mitigated. The relationship between housing and health is well established but multifactorial and complex. Transmission rates in housing are high, but existing data may not be sufficient to determine causal relationships and transmission pathways. COVID-19 mortality rates have been linked to houses of multiple occupation, temporary accommodation, multi-generation households, shortages of social housing and areas where overcrowding is more prevalent. However, the role of specific environmental, demographic and social factors is not yet known.