It’s been months since COVID-19 first hit our shores, and although we’re already in Phase 2, that doesn’t mean we can be less cautious about contracting the virus. As we all know by now, wearing a face mask is one of the easiest things we can do, but with the amount of different masks now available, which is the most effective?
Why Should We Wear Masks?
If you’ve been wearing a mask but you’re still wondering why this action is needed, here’s a simple explanation — wearing a mask is the most simple way to prevent the spread of COVID-19. Back in January, the public was recommended to only wear masks if they were unwell, recovering from illness or showed symptoms such as a fever, cough or runny nose. Wearing a mask helps to contain any small droplets that may come out of your mouth and nose when you talk, sneeze or cough, and reduces the chances of these droplets being spread to others.
By mid-April, it had become compulsory to wear a mask when stepping out of the house. Because COVID-19 can be asymptomatic, wearing a face mask not only reduces the possibility of you contracting the disease, but also the possibility of someone unknowingly passing it to others.
Types Of Face Masks
In their guide to masks and respirators, the Health Science Authority (HSA) lists 4 types of protection — cloth or paper face masks, surgical masks, N95 respirators and surgical N95 respirators. As seen from the table above, each variant has a specific purpose, filtration efficiency and fluid resistance.
While N95 masks are capable of filtering out airborne particles, the filtration efficiency of cloth or paper face masks seems to be the least effective when compared to the other three variants, due to their looser fit. While they may be able to shield the nose and mouth from releasing larger particles, they may not be able to protect the wearer as well as other variants. However, some cloth masks, such as the 3-ply cotton masks issued by the government, do seem to have a tighter fit compared to the home-made alternative.
Most Effective: N95 Mask & Surgical N95 Respirator
According to the Centers for Disease Control and Prevention (CDC), Surgical N95 Respirators are the most effective in terms of filtering airborne particles, as they are able to prevent up to 95% of particles between 100 – 300 nanometers (nm) in size — the average diameter of COVID-19 particles are estimated to be less than 125nm, with a Korean report recording them to be between 70 – 90nm. Used during haze situations in Singapore, the Surgical N95 Respirators are tighter fitting, but the design of it also makes it difficult for people to breathe in. However, according to Professor Leo Yee Sin, “if you find the N95 mask easy to breathe in and comfortable, you are wearing it wrong”. As the executive director of the National Centre for Infectious Diseases (NCID), he also suggested that N95 masks are mainly used by medical staff, and are not recommended for the general public.
N95 masks can be found at some local pharmacies, depending on availability, but they will be uncomfortable to wear and may affect your breathing.
Very Effective: Surgical Mask
Unbeknownst to many, there are actually several different types of surgical masks. They can vary in thickness, and this will affect their ability to protect the wearer, along with how easy it is to breathe through the mask. Because they are considered to be a medical device, according to the U.S. Food and Drug Administration (FDA), surgical masks are very effective against large-particle droplets, splashes, sprays or splatter, and may also reduce exposure of the wearer’s oral and respiratory liquids to others. Most typical surgical masks have a 3-ply structure — a waterproof front and back layer, with a non-woven fabric middle layer for filtration.
Its loose fit is also ideal for those who may be wearing them throughout the day, but extended use of the same surgical mask is not recommended. When using a disposable mask, it should be discarded once the inner lining becomes moist. A damaged or soiled mask diminishes its protection, and can do more damage to your health as you may be breathing in harmful bacteria. Do remember to discard your mask properly and safely — if left exposed, aerosolisation may take place, which results in substances left on the mask being dispersed and transmitted to others through the air. If you’re not sure of what the proper disposal method is, check out our guide here.
Least Effective: Cloth Mask
Although the use of cloth masks is the least effective method among the four listed, they are still much safer to wear compared to not wearing a mask at all. The government did issue a 3-ply, cotton face mask, which is similar to typical surgical masks, that are also made with a 3-ply structure. They are considered to be the least effective because while they prevent large particles from being released and spread by the wearer, they don’t necessarily prevent external fluids from reaching the wearer, especially if these fluids are bigger in diameter.
Cotton is the most commonly used material for reusable cloth masks, and the higher the thread count, the better the protection. In a recent study on aerosol filtration efficiency, it was found that cotton, natural silk and chiffon provide better protection, provided they have a tight weave, and higher threads per inch cotton with tighter weaves resulted in better filtration efficiencies. Materials such as polyester, spandex and satin were found to be less efficient.
If you plan on making your own reusable face masks, adding an additional built-in filtration layer would make them more effective. Check out our DIY guide here. However, do keep in mind that the CDC does not recommend cloth face masks for children or those who generally have trouble breathing.
Surgical masks seem to be the most effective and accessible for the general public. Overall, while N95 masks may be the most effective in terms of acting as a physical barrier, they are not as easily available as regular surgical masks may be, and they are also a lot more uncomfortable to wear — not ideal if you’re going to be wearing a mask all day. Surgical masks provide 95% bacterial filtration efficiency, and are also fluid resistant, acting as a barrier between liquid particles from the wearer and vice versa.