ABSTRACT
The spreading or transmission rate of COVID-19 caused by SARS-Cov2 infection is extremely fast and now almost all countries around the world reported the case of the disease. As a new type of coronavirus, it was identified that the size of SARS-Cov2 is about 100 nm (nano-meter). The spreading droplet from coughs is between 1 meter to another person around him. Therefore, the important task is to make a physical distancing more than 1 meter from the infected person. The transmission model of COVID-19 is different from other virus disease transmission such as through airborne or direct touch. The common transmission of COVID-19 is from the spreading of the droplet through the air as well as the other media surface. The transmission of respiratory infection via droplet will have different dimensions or sizes. When the droplet size of particles in diameter is less than 5μm (<5μm), this size will be referred to as droplet nuclei and it can be the residue of dried respiratory aerosol that results from evaporation of droplet coughed or sneezed into the atmosphere or by aerosolization of infective material. Another droplet size is 5 to 10 μm or more, it can be referred as a respiratory droplet or respiratory aerosols. One of the causes of the very fast-spreading transmission rate of COVID-19 is coming from droplet transmission through the air which contain virus in small droplet size type. It is recommended that airborne precautions for any situation involving the care of COVID-19 patients and consider the use of medical masks as an acceptable option in case of shortages of respirators (N95, FFP2 or FFP3). The other medical mask for general purposes in hospitals or clinics is a surgical mask. A surgical mask, also known as a procedure mask, medical mask, or simply as a face mask. Because of very rare and limited production volume of masks for ordinary people as well as special mask for medical also becomes very limited. Some homemade small industry tries to develop their own mask type and design by their own self. The use of homemade cloth base masks is becoming a new industry or an alternative for society to protect their health and activity from COVID-19. PM2.5 refers to atmospheric particulate matter (PM) that have a diameter of less than 2.5 micrometers. In the present study, the filtration efficiency of cloth cotton mask type by using detector particle type of PM2.5 is evaluated for reducing transmission of COVID-19. N95 mask type was used to be compared as special medical mask application with the cotton type mask for general use of people when the mask was very limited in the market. The analysis focused on the filtration efficiency of the mask that can reduce the particles entering the detector especially for particle size 2.5 micrometers or less to be used for droplet size of COVID-19 with the size of around that number.