World Health organization(WHO) COVID-19 Guidelines in Air conditioning What is vantilation and how can it prevent COVID-19 from spreading? Ventilation involves introducing clean air into a space while removing stale air, in order to maintain or improve air quality. Ventilation can be achieved naturally (e.g. by opening a window) or by installing a mechanical system. The spread of COVID-19 occurs most often when an infected person is in close or direct contact with another person. The risk of the spread of the virus is higher in crowded and poorly ventilated spaces where people spend long periods of time together in close proximity. Improving indoor ventilation can reduce the risk of the virus spreading indoors. Ventilation is not a standalone measure and it should be implemented as part of a comprehensive package of measures, such as physical distancing, wearing a mask, frequent hand cleaning, and coughing or sneezing into a bent elbow. Each of these is important to protect you against...