Pack your jumpers! With facilities managers being urged to increase air supply and exhaust ventilation systems to minimise the risk of coronavirus spreading through work environments, your office air quality will be better, however it might be a little cooler than usual.
The general advice in relation to COVID-19 is to supply as much outside air as reasonably possible, increasing the amount of air changes and reduce recirculated air to avoid building occupants from breathing in infected air via ventilation systems.
The advice comes from the Chartered Institution of Building Services Engineers (CIBSE), who have been providing information to engineers and building managers since the outbreak began. As the return to the office becomes more imminent you may wish to consult with your building services teams on the following advice:
In buildings with mechanical ventilation systems extended operation times are recommended. Change the clock times of system timers to start ventilation at nominal speed at least 2 hours before the building usage time and switch to lower speed 2 hours after the building usage time. At nights and weekends if your space is not used – do not switch ventilation off. Instead keep systems running at lower speed. Exhaust ventilation systems of toilets should always be kept on and make sure that under-pressure is created. It’s also important to instruct building occupants to flush toilets with the lid closed to avoid the virus reaching other surfaces.
Virus particles in return ducts can re-enter a building when centralised air handling units are equipped with recirculation sectors and therefore it is recommended to switch off any recirculated air. This is what may lead to problems with heating or cooling capacity and it may be necessary to make changes to ventilation and heating or cooling systems, depending on the building. However, cool it may get, preventing recirculated air from moving through your workspace can prevent contamination and protect public health.
Supply of outside air and the rate at which exhaust is ventilated should be increased in all buildings so that as much outdoor air is introduced as possible. In buildings without mechanical ventilation systems it is recommended to actively use operable windows as much as reasonably possible – even when this causes some thermal discomfort. In buildings with mechanical ventilation, window airing can be used to further boost ventilation. Avoid open windows in toilets to assure the right direction of ventilation.
It’s now more important than ever to ensure the regular filter replacement and maintenance works are performed on your building ventilation systems. Ensure you replace central outdoor air and extract air filters as usually, according to maintenance schedule.
Any changes made to any ventilation system or office air quality changes will need to be designed by a qualified mechanical engineer in collaboration with the building management teams to ensure that changes made are effective and do not impair comfort levels.