As countries emerge from the pandemic, it will be interesting to see what the ‘new normal’ looks like. Will workers return to their offi ces full time? Or will there be a new preference for more fl exible hours and for hybrid working (home + offi ce). Either way, there will be a new, heightened responsibility to account for microbiological hazards such as Covid-19 in the provision of safe indoor environments. Anu Katka, an indoor environment expert from Vaisala (Finland), examines the role that ventilation systems will play in protecting people in offi ces and other work spaces from future microbiological threats.