Types of Masks

In Order From Least to Greatest Average Filtration

Scarves and Bandanas

Scarves and bandanas are some of the most accessible options but because they are not actually masks they do not perform as such. According to the study, An Overview of Filtration Efficiency Through Masks: Mechanisms of the Aerosols Penetration, in the Science Direct Journal, they are 44% efficient at filtering large droplets and 49% efficient at filtering aerosols. These masks should not be worn in an area and only used as a last resort.

Masks with Built in Vents

Masks with built in vents can be used in most settings but it is discouraged. According to the study, An Overview of Filtration Efficiency Through Masks: Mechanisms of the Aerosols Penetration, while these masks are 90% effective at filtering large droplets and 90% effective at filtering aerosols, they do not protect others. Masks are supposed to filter out particles going into the mask and catch one’s particles going out. The issue with these masks is that the valve or vent doesn’t filter out one’s exhaled particles. This has been deemed the “selfish mask” by healthcare professionals because it protects only its wearer.

Two-layer Cotton Masks

Two-layer cotton masks are the most common homemade masks. According to the study, An Overview of filtration Efficiency Through Masks: Mechanisms of the Aerosols Penetration, they are 99.5% efficient at filtering large droplets and 82% effective at filtering aerosols. (This data is based upon two 500 thread count layers and the overall efficiency will become lower as the thread count drops). These masks are a good choice for public and indoor areas.

Surgical Masks

Surgical masks are normally used in healthcare settings. According to the study, An Overview of Filtration Efficiency Through Masks: Mechanisms of the Aerosols Penetration, these masks are 98.5% efficient at filtering large droplets and 89.5% efficient at filtering aerosols. Surgical masks are meant to be disposable but if used over and over again, their fibers deteriorate resulting in less filtration. These masks can also be worn in public or indoor areas.

Hybrid Masks

Hybrid masks are made up of more than three layers; these layers are made up of different fibers to increase filtration. According to the study, An Overview of Filtration Efficiency Through Masks: Mechanisms of the Aerosols Penetration, they are 96% efficient at filtering large droplets and 94% efficient at filtering aerosols. Hybrid masks are suitable for public and indoor areas.

N95, KN95, and KFN95 Respirator Masks

All of these masks have a five layer filter protection system. The difference between these masks are that N95 masks are up to FDA and NIOSH standards, KN95 masks are up to Chinese government standards and KF95 masks are up to the Korean government standards. The three masks are very similar with almost no differences. According to the study, An Overview of Filtration Efficiency Through Masks: Mechanisms of the Aerosols Penetration, all of these masks are around 99.9% efficient at filtering large droplets and 95% efficient at filtering aerosols. The CDC urges people to use hybrid or cotton masks so that more people who need them, like healthcare workers and first responders, will have access to them. Outlined in The Harvard-Westlake Return to School Plans and Guidlines Document, KN95 masks will be provided during the hybrid-model to students, faculty and staff.

What Students Have to Say

“I use respirator masks for regular wear that were shipped to me from Korea, but I wear surgical masks when I am working out because they are easier to breathe in,” Nicole Lee ’24 said.

“I mostly use a pleated cotton fabric masks that one of my friends made for me. I use the mask when going to the grocery story and walking around my neighborhood; it is quite versatile,” Lola Kim ’24 said.

“I use the KF95 masks,” Kriste An ’24. “They’ve been scientifically proven to be the best quality and were easily accessible for me. Ever since quarantine, I haven’t engaged in a lot of activities, but I would wear this mask when going to school events, the dentist, or walks,” An said.

Leave a Reply