FACE MASKS TO PREVENT COVID19 INFECTION
Which is the right mask for you and how to use it?
Wallet, keys, mobile phone and bag. This was the common checklist for everyone while leaving the house. But these days there is a new addition to this list – a face mask! This has become an essential item for all during the COVID19 pandemic. Suddenly we see our social media feeds filled with advertisements for different types of masks. Right from designer cloth masks, matching kalamkari and hand painted masks to costly state of the art N95 masks everyone seems to be shopping for them.
But there is still a lot of confusion about the different kinds of masks, when and how to use them correctly. Please read on to clear some of your doubts about face masks.
There are 3 main types of masks - Cloth face masks, surgical masks and N95 masks.
1. Cloth face masks
These are the most common, easily available and cost effective face coverings available on the market. With some basic sewing skills you can even make them at home.
Even though cloth masks do not effectively block the virus, research has shown that when used correctly along with adequate social distancing (maintaining 6ft distance from others) and correct hand washing or hand sanitizer use, transmission of COVID19 can be greatly reduced.
If 80% of the population wears masks in all public spaces along with adequate social distancing, scientists say that the outbreak can be completely stopped.
Choosing the right type of fabric face mask and following certain precautions while handling them can make all the difference!
Choose a cotton, densely woven material. You can check this by holding your mask up to the light. The best mask would be that which allows least light to penetrate.
Click HERE to learn how to make your own cloth mask!
2. Surgical mask or medical mask
These are disposable masks made of non woven plastic/polymer fabric.
They are generally 3 layered -
Innermost soft non woven layer,
Middle filter for large particles and germs
Outermost hydrophobic layer.
They are more effective in blocking larger droplets and secretions, for example when someone coughs or sneezes close to you. This is why they are used in healthcare setups and by front line health workers where there is contact with infected secretions.
Research has shown that in public areas where distance of 6ft can be maintained and there is encounter with asymptomatic cases, their efficacy is the same as a cloth mask. They don't block small aerosols and viruses.
Surgical masks are single use only. DO NOT REUSE ! Reusing or washing a surgical mask will make it less effective and in fact increase the risk of virus transmission.
These masks are not recommended for general use as it could lead to a shortage for frontline workers.
3. N95 Mask
These are masks made of electrostatic polypropylene material with an ergonomic design to seal nose and chin tightly. Their manufacture and distribution are strictly regulated by the National Institute of Occupational Safety and Health (NIOSH).
These masks have a 95% efficacy of filtering virus particles. They stop movement of virus particles by electrostatic property of the material. They can filter particles as small as 0.3 microns. Even the smallest respiratory aerosols are usually above that size.
In general settings when social distancing can be maintained these masks are unnecessary. They are not recommended for general use due to shortage for frontline workers.
These are SINGLE USE only. The electrostatic property of the material is compromised by contact with detergents or chemical disinfectants. The CDC recommends reuse of N95 masks only in case of critical shortages after disinfection by specific methods like UV sterilisation.
Some of these masks come with valves to make breathing easier and prevent moisture build up. Valved masks are not recommended as they do not filter the exhaled air.
BEWARE of dubious sellers selling fake N95 masks! List of approved brands with the corresponding approval numbers can be found on the NIOSH website. Any mask without a model and approval number printed on it is probably fake.
Hope this article has cleared some of your doubts regarding face masks for COVID19
Stay safe, be prepared and stay positive!
References and further reading:
1. Office of Principle scientific advisor to the government of India manual for use of facemasks - http://184.108.40.206/WriteReadData/userfiles/FINAL%20MASK%20MANUAL.pdf
2. Konda A, Prakash A, Moss GA, Schmoldt M, Grant GD, Guha S. Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks. ACS Nano. 2020 Apr 24
3. Ma QX, Shan H, Zhang HL, Li GM, Yang RM, Chen JM. Potential utilities of mask-wearing and instant hand hygiene for fighting SARS-CoV-2. J Med Virol. 2020. PMID: 32232986.
5. WHO guidance on mask use - https://www.who.int/emergencies/diseases/novel-coronavirus-2019/advice-for-public/when-and-how-to-use-masks