The German government is investing €500m (£452m; $488m) in improving ventilation systems in public buildings to help stop the spread of coronavirus. The grants will go to improve the air circulation in public offices, museums, theatres, universities and schools. Private firms are not yet eligible. Viruses spread on tiny droplets called aerosols, exhaled by infected people – especially when they sneeze or cough. Studies suggest they can remain in a room’s air for at least eight minutes. Colder weather puts more people at risk because they spend more time indoors. The main aim is to upgrade existing air conditioning systems, rather than install new ones, which costs more. Each upgrade is eligible for a maximum of €100,000. Funding is also available for CO2 sensors which indicate when the air in a room is unhealthily stale. The grants will be allocated from Tuesday.(BBC)…[+]