“The ultimate take away from this webinar should be that masks are effective in protecting you from COVID-19,” said Dr Arnab Bhattacharya, a material scientist with Tata Institute of Fundamental Research (TIFR) in Mumbai, who has been involved with a project on testing the efficacy of different mask materials along with other researchers at the institute.
The scientist on Sunday was addressing a webinar hosted by an organisation called Indian Scientists’ Response to COVID-19 (ISRC), in which he gave detailed explanations to queries on the use of masks during the pandemic.
The scientist began by citing a multitude of studies which established the efficacy of masks in controlling the spread of the pandemic. “Before we delve into what mask types should be worn by whom, you should know that if you just wear mask regardless of the levels of filtration, you will help curb the spread of the virus,” said Dr Bhattacharya. The doctor evidenced this by reading abstracts from studies which have showcased that mask use have been the most efficient form of curbing the pandemic, outside clinical intervention. “Any other social practice and precaution observed without wearing masks will not be efficient in curbing the pandemic. So wearing a mask is your best bet,” said the material scientist.
Deciding a suitable mask for yourself
The scientist stressed that N-95 masks are the most suitable for medical practitioners or any other essential service provider who is likely to be in crowded spaces or in the vicinity of potential COVID-19 patients. “For all other regular people, wearing a cloth mask or a surgical ply mask is the best, along with practicing physical distancing,” said Dr Bhattacharya.
The reason for this recommendation, he said, is that the point of the cloth mask and surgical mask is to ensure that the wearer is protected from large droplets, and so are others around him. These masks are also meant to be a little loose fitted as compared to N-95 masks, so that they remain comfortable to be worn for long hours. “If these masks are too uncomfortable and completely sealed, you will just not be able to breathe and will tend to take them off, which will defeat the whole point of the exercise,” explained the scientist. Furthermore, cloth masks are easy to re-use, unlike N-95 masks.
However, as the N-95 masks filter out over 95 per cent of particles smaller than 0.3 microns, they are more suitable for those who need to be protected from aerosol particles. These particles are more likely to be present inside hospitals, where certain surgical and clinical procedures lead to the formation of such particles.
However, all people, regardless of their profession, should stay away from masks with valves according to the scientist. These valves are placed in order to let people breathe out easier and are useful in places where there is a lot of dust. “Wearing a mask during the pandemic is meant to stop you from circulating air, so if you easily breath out your air into the environment around you, the virus is likely to spread further,” explained the material scientist.
How to wear masks
More important than the quality of the mask, is the way in which one wears it. If the mask is not properly worn or is loose fitted, it will not provide any form of protection to the wearer and others around him. “Every mask needs to be worn from the bridge of the nose to your chin, while its straps should be placed behind your head and adjusted rather than behind your ears. Cloth masks and surgical masks can have some gap on its sides to let air out so that the wearer is comfortable, but it should not be completely loose,” said Dr Bhattacharya.
Meanwhile, the N-95 masks need to be completely sealed to ones face to provide the amount of filtration it is meant to. Furthermore, all masks should be removed by touching the straps and not the mask itself. “Many healthcare workers are getting infected because they doff the mask by touching it rather than just holding it by the straps,” he added.
Cloth masks, which can be made easily at home by using old t-shirts, are efficient enough to filter out at least 50 per cent of particles and can be easily washed and reused. Dr Bhattacharya recommended the use of two cloth masks on alternate days so the user can wash one at the end of each day and wait for a day for it to dry. The mask should be washed using regular detergent and nothing else. “Furthermore, these masks should be made using material such as old t-shirts or towels. Because frayed cloth traps even more particles in it,” says the scientist.
For re-using N-95 masks, the easiest way to disinfect them is by waiting for a week before using them again. Other methods, such as disinfecting them by using alcohol or other techniques to kill virus particles will also damage the intermediary layer of the mask which has an electrical charge to capture particles. “Heat and time will do the trick to disinfect most of your N-95 mask within a week,” said the scientist.