COVID-19: How to Make Indoor Spaces Safer  | Virus World | Scoop.it

From good ventilation to redesigning spaces, here are ways to help reduce the risk of transmission in closed settings. With the winter season upon us in the Northern Hemisphere, cold weather conditions are forcing people to stay indoors. Coupled with children heading back to school and offices reopening, there is looming concern around a second wave of the coronavirus in Europe, North America and other parts of the world. COVID-19 is a highly contagious respiratory disease. In closed and crowded indoor settings, there is a higher risk of it spreading compared with the outdoors, where the flow of fresh air can dilute and dissipate the virus particles. According to the WHO, the coronavirus is primarily transmitted by droplets spread through direct or close contact with an infected person, and indirect contact with contaminated surfaces, also known as fomite transmission. But there is also the possibility of airborne transmission in crowded indoor settings with poor ventilation, such as restaurants, gyms, night clubs and offices. A number of measures can be taken to reduce the risk of infection in such closed settings.

Natural ventilation

Ventilation is the introduction of fresh air into an indoor space while the stale air is pushed outside.  Whether at home or in public buildings, such as schools and offices, ventilation can be improved by simply opening windows and doors whenever possible. Luca Fontana, a water, sanitation and hygiene (WASH) specialist consultant at the WHO, told Al Jazeera ventilation is “one part of the big package of infection prevention and control measures” along with physical distancing, hand hygiene and face masks. “The general proposal of ventilation in the building is to provide healthy air for breathing by both diluting the pollutant originating in the building and removing the pollutant from the space itself,” he said in a recent Facebook live Q&A.

HVAC systems

In public spaces, ventilation through mechanical measures like heating, ventilation and air conditioning (HVAC) systems can be helpful in improving indoor air quality. According to the WHO, a well-maintained and operated HVAC system can reduce the spread of COVID-19 in indoor spaces by increasing the rate of air change, reducing recirculation of air and increasing the use of outdoor air. The air should preferably not be recirculated and the HVAC systems should be regularly inspected, maintained and cleaned by professionals. The WHO has outlined technical specifications for operating and maintaining these systems in the context of COVID-19.  

Filters and fans

High-efficiency particulate air (HEPA) filters that are commonly used in aeroplanes and hospitals are another useful tool to remove viruses and germs from the atmosphere. These can minimise the duration of the exposure to any potential infectious materials produced by a cough or sneeze. The use of fans, with certain considerations, can improve air circulation and reduce pockets of stagnant air in an enclosed space. “A table or pedestal fan is safe for air circulation among family members living together who are not infected with the virus that causes COVID-19,” said Maria Neira, director of the department of public health and environment at the WHO. “However, fans should be avoided when people who are not part of the immediate family [are present], since some people could have the virus despite not having symptoms,” she added. “Air blowing from an infected person directly at another in a closed space might increase the transmission of the virus from one person to another.” When using a ceiling fan, Fontana said it was important to maintain good ventilation – by opening a window for instance – as an efficient way to increase the exchange of air between indoors and outdoors...