COVID-19: Ventilation of Indoor Spaces to Stop the Spread of Coronavirus - updated

This government guidance has been updated to include information about the new COVID-19 variant.

Due to this and given the increased risk of transmitting COVID-19, extra caution is advised. The guidance emphasises the important of ventilation, noting that letting fresh air into indoor spaces can help remove air that contains virus particles and prevent the spread of

Coronavirus (COVID-19).

Workplaces

Ventilation should be considered as part of making your workplace or indoor public space COVID-secure.

It is important to identify and deal with areas that are not well ventilated. The more people occupying an area that is poorly ventilated, and the longer they remain in it, the greater the risk of spread of COVID-19.

Control measures such as avoiding certain activities or gatherings, restricting or reducing the duration of activities, providing ventilation breaks during or between room usage should be considered alongside ventilation for reducing the risk of airborne transmission.

Any actions to improve ventilation should not compromise other aspects of safety and security (for example, avoid propping open fire doors), and should consider other consequences such as health and wellbeing impacts from thermal discomfort.

Employers should provide employees with clear guidance on ventilation, why it is important, and instruction on how to achieve and maintain good natural ventilation or to operate systems if there are user controls.

Mechanical ventilation systems must be maintained in line with manufacturers’ instructions. Set ventilation systems to using a fresh air supply and not recirculating indoor air, where possible. For some existing and older buildings, ventilation systems may not have been designed to meet current standards and additional mitigations may be needed. If you are unsure, the guidance stresses that the advice of a heating, ventilation and air conditioning (HVAC) engineer or adviser should be sought.

The guidance, which also covers ventilation in vehicles, is available here.

Public Health England/Cabinet Office May 2021