"Mechanisms of transmission through the air are called 'airborne aerosols' and 'droplets'. Both are related to the size of airborne particles," Dr. Dicky Budiman MScPH, Ph.D. (Can) of Griffith University, Australia, informed during an online discussion monitored here on Thursday.
He said cases of COVID-19 transmission in indoor spaces had been in the spotlight, such as in China and South Korea, and later became the subject of scientific research.
Transmission in the two countries occurred quickly due to poor air circulation in indoor spaces, he noted. Air conditioning and ventilation systems recirculate air in a room instead of using outside air, which is crucial for maintaining good indoor air quality, he said.
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The potential for virus transmission during outdoor activities is smaller, but people can still get infected if they do not use a mask, he cautioned.
He emphasized that the potential for exposure in an enclosed room is 20 times higher than outdoors.
"In every crowded event, there is something called a 'super spreader' that carries a lot of viruses. Especially when it comes to the Delta variant, which has 100 times the number of viruses compared to the previous one," he expounded.
He also advised people to use two-layer masks -- medical and cloth -- and never open them in enclosed public spaces. Then, most importantly, reduce mobility and avoid crowds, he added.
Taking note of the air circulation issue, building consultant, Dedy El Rashid, urged building managers to start paying attention to air ventilation systems to prevent the transmission of COVID-19.
"We recommend increasing the intake of clean air by conducting air change two times and using better filters that have higher efficiency," he said.
Building managers can also add facilities by installing standard ultraviolet C rays to kill bacteria and viruses, although further research needs to be conducted on their effectiveness in inactivating SARS-CoV-2, he added.
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