BRONZE

So Many Masks - What to Wear?

I am conducting experiments to find out what type of mask is the most effective for protection against an airborne disease. I am also using the designs of the successful mask(s) to create the most ideal mask.
Cooper Choi
Grade 8

Hypothesis

Problem

Since the beginning of the pandemic, masks have become one of the most essential pieces of equipment. Thousands of different brands have produced their own models, which vary in type of materials, number of layers, size, and more. This is where a problem arises. While many masks properly filter out particles and keep us safe, countless others are ineffective in this. Thus, it is difficult to determine which masks protect one from the virus, even more so when finding one that is comfortable and cost efficient. The governments throughout the world have urged their citizens to wear masks, but which ones? There are many studies discussing this issue, but due to their mismatching data, I have decided to conduct experiments to find out which masks are the safest, most comfortable, most durable, and cost efficient.

Objective

There are two main objectives in my experiments:

*I will be conducting three experiments in total; two testing safety and one testing comfortability. Other factors of a mask, such as durability and cost efficiency will be analyzed through research. 

  • Determine, out of the masks I test, what type of mask is the most safe, comfortable, durable, and cost efficient overall  (The Best Mask)
  • Analyze the design/characteristics of the masks which had the most positive results in each experiment and create a design for what the most ideal mask would look like.

Definitions: 

Best Mask:

  • A mask that is safe, comfortable, durable, and cost efficient, especially in the above factors which are deemed more important in the list below

Factors of a Mask’s Design (in order of priority within my experiments) 

  • 1. Safety 
  • 2. Comfort
  • 3. Durability 
  • 4. Cost Efficiency
  • *Durability + Cost Efficency = Financial Choice

  • *I am conducting a total of 3 experiments and research to test these 4 factors

  • Safety - 2 experiments

  • Comfort - 1 experiment

  • Durbaility + Cost Efficiency - research

Overall Scientific Question and Hypothesis: 

- Scientific Question: How does the type and design of a mask (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) that is worn affect the wearer’s safety, comfort, and financial choice of masks?

- Hypothesis: If five different masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) are worn in experiments and research regarding safety, comfortability, and financial choice, then the KF94 mask will be most successful, because, despite it not being made of any polypropylene, it filters 94% of particles and has 4 layers of nonwoven fabric, a material which is efficient at filtering, as well as being flexible. 

    - Additionally, in the same experiments and research, the cloth mask will be the least successful, because it only has one layer, has no nose wire to prevent air from escaping or the mask from slipping down, and the polyester used in it is the only material with no characteristics related to filtering properties. 

Research

Background Information

Masks Used in the Experiments:

- Dental Mask (Brand: Boomcare)

-  Cloth Mask (Brand: Bauer)

-  KF94 Mask (Brand: P&B)

- KF80 Mask (Brand: Welkeeps)

- KN95 Mask (Brand: Medsup Canada)

(In KF80, KF94, and KN95, the "KF" or "KN" stands for the country where the mask was designed by and the number stands for the percentage of particles that the mask can filter through) 

- *HEPA (High efficiency particulate air-filter) masks are masks which have a more thorough filter than normal surgical masks 

  - HEPA masks include: 

    - N95, KN95, KF94, KF80, and other masks which have a similarly structured name

Further Information on Masks:

- Dental Mask (Brand: Boomcare)  

  • Non-medical, Protective 
  • Price: About $20.00 for 50 - approx $0.40 for 1
  • Material: 67% non-woven fabric, 33% meltblown fabric 
  • Layer Number: 3 - Non-woven + Meltblown + Non-woven
  • Single use recommended 
  • Wire Material: Unknown
  • (Photos: Left - Mask, Right - Cross Section of Mask Layers) 

-  Cloth Mask (Brand: Bauer)

  • Non-medical, Protective
  • Price: About $12.00 for 1
  • Material 100% polyester 
  • Layer Number: 1 - Polyester
  • Multiple use recommended 
  • Reversible 
  • No nose wire 
  • (Photos: Left - Mask, Right - No Image Because Mask Only Has One Layer) 

-  KF94 Mask (Brand: P&B)

  • Non-medical, protective 
  • Price: about $17.00 for 12 - approx 1.40 for 1
  • Material: Non-woven, meltblown fabric
  • Layer Number: 4 - Lining (Non-woven Fabric) + Intermediate Layer (Non-woven Fabric) + Filter (Non-woven Fabric) + Outer Fabric (Non-woven Fabric) 
  • Single use recommended
  • Wire Material: Polypropylene Double Wire
  • (Photos: Left - Mask, Right - Cross Section of Mask Layers) 

- KF80 Mask (Brand: Welkeeps)

  • Non-medical, Yellow Dust protective 
  • Price: About $50.00 for 25 - approx $2.00 for 1
  • Materials: Nonwoven Fabric, Polypropylene Nonwoven Fabric
  • Layer Number: 4 - Nonwoven Fabric(Lining) + Polypropylene Nonwoven Fabric (Filter) + Polypropylene Nonwoven Fabric (Outer Layer) + Rest (Unknown) 
  • Single use recommended
  • Wire Material: Sheathed Double Iron Core
  • (Photos: Left - Mask, Right - Cross Section of Mask Layers) 

- KN95 Mask (Brand: Medsup Canada)

  • Non-medical, protective
  • Price: About $25.00 for 20 - approx $1.25 for 1
  • Material: Polypropylene SBPP 30%, MBPP 30%, WMPP 40%
  • Layer Number: 4 - Non-woven (Filter) + Rest (Unknown) 
  • Single use recommended
  • Wire Material: Unknown 
  • (Photos: Left - Mask, Right - Cross Section of Mask Layers) 

Sources:

Further Background Research on Materials of Masks

Dental Mask

- Non-woven + Meltblown + Non-woven

Cloth Mask

- Polyester 

KF94 Mask

- Non-woven Fabric + Non-woven Fabric + Non-woven Fabric + Non-woven Fabric 

KF80 Mask

- Nonwoven Fabric + Polypropylene Nonwoven Fabric + Polypropylene Nonwoven Fabric + Unknown 

KN95 Mask

- Non-woven + 3xUnknown

Materials:

Nonwoven Fabric (2 layers in dental mask, 4 layers in KF94 mask, 1 or more layers in KF80 mask, 1 or more layers in KN95 mask)

- Nonwoven Fabric Characteristics: 

  • Absorbency
  • Bacterial barrier
  • Cushioning
  • Filtering
  • Flame retardancy
  • Liquid repellency
  • Resilience
  • Softness
  • Sterility
  • Strength
  • Stretch
  • Washability

(Source: https://www.inda.org/about-nonwovens/ - Might be some bias but still credible) 

Polypropylene Nonwoven Fabric (2 layers in KF80 Mask) 

- Polypropylene Nonwoven Fabric Characteristics:

Nonwoven Fabric Characteristics + 

  • Semi-rigid
  • Translucent
  • Good chemical resistance
  • Tough
  • Good fatigue resistance
  • Integral hinge property
  • Good heat resistance

(Source: https://www.bpf.co.uk/plastipedia/polymers/pp.aspx)

Polyester (1 layer in cloth mask)

  • durable
  • moisture-resistant
  • retains shape
  • coarse
  • non-biodegradable 

(Source: https://www.masterclass.com/articles/polyester-fabric-guide#what-are-the-characteristics-of-polyester-fabric)

Melt-Blown Fabric (1 layer in dental mask)

- Melt-Blown Fabric Characteristics: 

  • softness
  • elasticity
  • wettability
  • chemical resistance of formed fibers

(Source: https://www.entechsrl.com/sectors/melt-blown/#:~:text=Basic%20characteristics%20of%20the%20Melt,as%2010%20to%2015%20%C2%B5m. )

Further Background Research on Wire Materials of a Mask

Dental Mask

- Wire Material: Unknown

Cloth Mask

- Wire Material: No Nose Wire

KF94 Mask

- Wire Material: Polypropylene Double Wire

KF80 Mask

- Wire Material: Sheathed Double Iron Core

KN95 Mask

Wire Material: Unknown

Materials:

Polypropylene (In KF94 mask)

- Polypropylene Characteristics:

  • Semi-rigid
  • Translucent
  • Good chemical resistance
  • Tough
  • Good fatigue resistance
  • Integral hinge property
  • Good heat resistance

(Source: https://www.bpf.co.uk/plastipedia/polymers/pp.aspx)

Sheathed Double Iron Core (In KF80 Mask)

Sheathed - similarly to how electric cables are

Iron

- Iron characteristics: 

  • Ductile (Being able to be bent out of shape while mainaining properties)
  • soft
  • good conductor 

(Source: https://www.chemicool.com/elements/iron.html#:~:text=Characteristics%3A,%2C%20forming%20red%2Dbrown%20oxides. )

Other Papers/Researches/Articles on Masks 

Coronavirus Face Masks & Protection FAQs - Johns Hopkins Medicine - Lisa Lockerd Maragakis, M.D., M.P.H. https://www.hopkinsmedicine.org/health/conditions-and-diseases/coronavirus/coronavirus-face-masks-what-you-need-to-know - Last updated: January 29th, 2021

- Article

 - bandannas(too many openings), gaiters(too thin), and masks with valves(particles escape through valve) are ineffective in protection 

- the article defines a best mask as:

  - being able to be worn without frequent adjustment 

    - does not slip down while moving

    - comfortable 

  - fits face without any gaps 

  - has multiple layers of fabric 

  - flexible but strong wire

- more layers do not mean more effective - might make it hard to breath which means that mask must be adjusted more

  - double masks are not neccessary

- recommended materials for homemade masks: densley woven cotten fabrics 

  - don't use stretchy knits  

- face shield recommended only with a mask 

A User's Guide To Masks: What's Best At Protecting Others (And Yourself) - NPR (National Public Radio - US) - Maria Godoy - https://www.npr.org/sections/goatsandsoda/2020/07/01/880621610/a-users-guide-to-masks-what-s-best-at-protecting-others-and-yourself - Posted: July 1st, 2020

- Article

- cloth masks:

  - tightness of weaves are important 

    - eg). a knit of a scarf as compared to that of tights 

  - cotton is effective as a material

    - cotton has a 3D structure, which creates a more dynamic surface for particles to get caught up in 

    - polyester is another effective material

- multiple layers is effective

- best filter material is polypropylene

  - polypropylene is also electrostatic - traps particles

    - electrostatic charge is lost when mask is washed (but can be regained through friction)

    - two layers + polypropylene filter = about 70% of particles filtered

  - do not use coffee filters as filters (breath goes around the mask rather than through it) 

shape of mask is also important

  - masks with folds are effective in this

- gaiters are so-so, do not use masks with valves

- wet masks are harder to breath through

- N95 (=KN95) masks are highly effective due to their composition of multiple layers of polyproylene fabric

  - there is a widespread number of counterfeit KN95 masks in the U.S.

- surgical (dental) masks

  - meant to filter large particles, usually not small ones

  - performance varies

  - most are made of paper, some with polypropylene

  - are good at stopping particles from escaping a person with a virus but not neccessarily in protecting a person from incoming particles

Filtration Efficiencies of Nanoscale Aerosol by Cloth Mask Materials Used to Slow the Spread of SARS-CoV‑2 - ACS Nano (American Peer-Review Journal) - Christopher D. Zangmeister,* James G. Radney, Edward P. Vicenzi,§ and Jamie L. Weaver§ - https://pubs.acs.org/doi/pdf/10.1021/acsnano.0c05025 - Published: March 8, 2021

- Paper/Experiment

- *Note that all results are ONLY FOR CLOTH MASKS, NOT for single-use masks or others. 

- Purpose: measure the filter efficency and other factors (quality, construction parameters, and differential pressure) of 32 different cloth mask materials

  - "14 cotton, 1 wool, 9 synthetic, 4 synthetic blends, and 4 synthetic/cotton blends" 

  - surgical (dental) mask and N95 masks were also tested

- no cloth mask performed as well as the N95

- best performing cloth mask: moderately thick yarn, visibly raised fibers

JKMS (Journal of Korean Medical Science) - Linked to PMC (US National Library of Medicine National Institutes of Health) - What Type of Face Mask Is Appropriate for Everyone-Mask-Wearing Policy amidst COVID-19 Pandemic? - Mi-Na Kim - Published May 25th, 2020 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7246185/

- Paper/Research

- Purpose: prove that HEPA masks are not the best and if so, find out what masks are the most effective

- HEPA are more effective than surgical mask filters (when the mask properly covers the wearer's face)

- however, paper states that comfort is more essential than safety for long-term use; HEPA masks are more tight in order to be effective, causing them to require frequent adjustment in long-term use

- they are also not recommended for more than 4 hours because due to their tight fit, they trap the harmful particles inside the mask, harming the mask filter faster

  - surgical (dental) masks

    - its primary function is to protect others from body fluids during operations or examinations - thus, it requires less adjustment but is corresponsingly loose-fitting

    - pleated structure prevents fluids from passing through

  - cotton cloth masks 

    - prevents a significant amount of fluids from pasing through

    - only 1/3 as efficent as the surgical mask

- Results: Although a HEPA mask is effective in filtering particles, it comes at a disadvantage for comfort and prolonged use/reusability; thus, surgical masks are the most effective for long-term use 

- AAAS (American Association for the Advancement of Science) - Low-cost measurement of face mask efficacy for filtering expelled droplets during speech - Emma P. Fischer, Martin C. Fischer, David Grass, Isaac Henrion, Warren S. Warren, Eric Westman - Published September 2nd, 2020 - https://advances.sciencemag.org/content/6/36/eabd3083

- Paper/Experiment

- Purpose: testing the amount of fluid that passes through during talking/sneezing in order to find the most effective mask in terms of safety

- Results: 

  - Masks in order of best performing to least (approximate number of droplets that got past the mask) 

    - N95 mask (0)

    - Surgical mask (0-0.15)

    - Polyester-cotton mask (0.25-0.75) 

    - Polypropylene mask (0.5-0.1)

    - Various cotton masks

    - Knitted (0.1-0.6) 

    - Bandanna (0.2-1.1)

    - Gaiter (0.65+)

- PMC (US National Library of Medicine National Institutes of Health) - Effectiveness of Surgical and Cotton Masks in Blocking SARS–CoV-2: A Controlled Comparison in 4 Patients - Seongman Bae, MD,* Min-Chul Kim, MD,* Ji Yeun Kim, PhD,* Hye-Hee Cha, BS, Joon Seo Lim, PhD, Jiwon Jung, MD, Min-Jae Kim, MD, Dong Kyu Oh, MD, Mi-Kyung Lee, MD, Seong-Ho Choi, MD, Minki Sung, PhD, Sang-Bum Hong, MD, Jin-Won Chung, MD, and Sung-Han Kim, MD - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7153751/ - Published April 6th, 2020

- Paper/Experiment

- Purpose: to see if surgical and cloth masks are equally effective as N95 masks when preventing a patient infected with Covid-19 from spreading it to others

- Masks tested:

  - surgical mask ("3 layers [inner surface mixed with polypropylene and polyethylene, polypropylene filter, and polypropylene outer surface]") 

  - cloth mask (reusable, cotton)

- Results: neither mask was effective in preventing the spread of Covid-19 through coughing

Variables

Basic Introduction to Experiments

Experiments (Total of Three) 
- 1. Testing Safety (How much air the mask lets through) 
  - Testing if a candle can be blown out while wearing a certain type of mask
  - No human participants

  - Independent Variables: Type of mask 

  - Dependent Variable: Whether or not the candle was blown out (yes/no) and number of blows taken to blow candle out. 

- 2. Testing Safety (How much water the mask lets through) 
  - Testing, when a certain type of mask is used as a filter, how much water can pass through out of the 30ml that is poured in 
  - No human participants 

  - Independent Variables: Type of mask 

  - Dependent Variable: Amount of water that passes/seeps through the mask out of 30ml (ml)

- 3. Testing Comfort (How fast the mask causes fogging on the wearer's glasses) 
  - Testing, when a certain type of mask is worn with glasses at -17°C and 0°C, how long it takes for the glasses to fog up to an extent 
    that the wearer has to take them off. 
  - Human participants involved because I do not wear glasses (but ONLY MY PARENTS - only my mother)

  - Independent Variable: Type of Mask 

  - Dependent Variable: Time that it takes for the glasses to fog up to an extent that the wearer needs to clean them. (seconds) 

Procedure

Experiment Procedure and Extented Information

 Experiment 1 - Safety

  • Materials: Candle, lighter, masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask)
  • Location: Indoors
  • One of the most important factors of a mask is its safety and ability to filter out particles in the air. This can be related to how well a mask lets air pass through. 
  • In this experiment, I will be testing how well air can pass through each mask type; however, it should be noted that a mask cutting off much air from passing through is not always effective, for a mask should let some air pass through for the purpose of proper breathing. 
  • Procedure: The candle will be lit, picked up, and held approximately 5-7cm from my mouth. I will attempt to blow the candle out. I will blow up to a maximum of five times. If the candle is not blown out after the maximum of five blows, it will be recorded as such. I will record whether or not the candle was blown out and the number of blows it took to blow it out. 
  • Number of Trials: 5
  • Control Experiment: No mask
  • Independent Variables: Type of mask 
  • Dependent Variable: Whether or not the candle was blown out (yes/no) and number of blows taken to blow candle out. 
  • Control Variables: type and size of candle, height and distance from body the candle is placed when blowing it, location/room where experiment is conducted, strength of the air which I blow (as strong as possible, but I realize that this might not always be consistent), brands for each mask
  • Scientific Question: How does the type of mask (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) that is worn affect whether or not a candle can be blown out in five blows (No Units, No Measuring Tool)? 

  • Hypothesis:  If several different masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) are worn while trying to blow out a candle, and whether or not the candle was blown out and the number of blows it took to do so is recorded, then the candle will not be blown out while wearing the KF94, KF80, and KN95 masks, because they have a larger number of layers and their texture is more stiff and rigid due to the inclusion of polypropylene nonwoven fabric. 

  • The candle will be blown out while wearing the dental and cloth masks because they have a smaller number of layers and are more pliable. 

Experiment 2 - Safety

  • Materials: timer (computer), phone, phone stand, 250ml beaker, 30ml plastic cup, masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask), tapwater 
  • Location: Indoors
  • Masks are also used to prevent spit and other harmful liquids from escaping or entering the wearer’s body.
  • In this experiment, I will be testing how well a mask lets water pass/seep through it. 
  • Procedure: The mask will be used as a filter for water. The mask will be positioned over a beaker, completely covering the top, and then 30ml of water will be carefully poured on it. I will wait five minutes and then remove the mask and whatever water that has not passed/seeped through. Then, I will measure the amount of water that has seeped through into the beaker. 
  • Number of Trials/Experiment: 3
  • Control Experiment: No mask 
  • Independent Variables: Type of mask 
  • Dependent Variable: Amount of water that passes/seeps through the mask out of 30ml (ml)
  • Control Variables: type of water used (tapwater), amount of water used in each trial, beaker size, plastic measuring cup size, pace when pouring water onto mask, duration of each trial, brand of each mask
  • The experiment, including the three trials for each, will be conducted twice, with one where the outside of the mask is facing up and another where the inside of the mask is facing up. 
  • Scientific Question: How does the type of mask (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) that is used affect the amount (or fraction) of water that can be filtered through it out of 30ml (ml, measuring cup)? 

  • Hypothesis:  If several different masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) are used to filter 30ml of water, and the amount of water that passes through the filter after 5 minutes is recorded, then all masks except for the cloth mask will prevent any water from passing through because they all have multiple layers of nonwoven fiber, a material that has some degree of liquid repellency. 

Experiment 3 - Comfort

  • Materials:  timer (phone), phone stand, masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask)
  • Location: Outdoors
  • A less important yet significant factor within mask is comfort; if I mask is too tight or keeps on slipping down, the wearer has to constantly touch their face while adjusting, which defeats the purpose of wearing one. One of the most prominent parts of comfort is the amount of fogging on glasses wearing a mask causes. 
  • In this experiment, I will be testing what mask is the least/most prone to causing fogging on glasses when worn with them
  • Procedure: The mask wearer, also wearing glasses, will walk back and forth between two points at a constant speed. They will take their glasses off when they judge that the fog is hindering their vision; the time (seconds) until they remove their glasses will be recorded. Due to the setting of the experiment, if the wearer has not taken off their glasses after two minutes (120 seconds), the experiment will end. 
  • The experiment will be conducted twice, at different temperatures, in order to observe if temperature affects the results  
  • Number of Trials/Experiment: 3 
  • Control Experiment: No Mask
  • Independent Variable: Type of Mask 
  • Dependent Variable: Time that it takes for the glasses to fog up to an extent that the wearer needs to clean them. (seconds) 
  • Control Variables: wearer of the mask, temperature of the location where each experiment is conducted in, location where the experiment is conducted, type of glasses used, time of day during which each experiment is conducted, consistency of brands for each mask, movement of mask wearer during the experiment, consistency of breathing from the mask wearer, consistency in walking pace, brand of each mask
  • In order to observe the affect of temperature on the results, and whether or not it causes any experimental error, I will conduct this experiment, along with the the three trials for each, at two different temperatures. 
  • Scientific Question: How does the type of mask (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) that is worn affect the time that is takes for the wearer’s glasses to fog up to an extent that they need to be taken off (Seconds, Timer)? 

  • Hypothesis: If several different masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) are worn with glasses and the time it took for the glasses to fog up to an extent that the wearer has to take them off is recorded, then the KF80 mask will take the longest to do so because its wire is made of sheathed double iron core, a material that is ductile, and therefore can be bent to fit the wearer while maintainging its properties of strength. 

  • The glasses will be taken off after the shortest time when wearing the cloth mask because it does not have any wire at all.

  • Extended Reasoning (In Background Information Section): 

  • The strength and flexibility of the mask’s wire often affects how much fogging is caused on the wearer’s glasses; a wire has to be flexible enough to be bent to match the wearer's face, but als has to be to strong enough to stay in that position once bent into it. 

Observations

Experiment 1

- Table:

 

Whether or  Not Candle Was Blown Out (Trial 1)

Whether or  Not Candle Was Blown Out (Trial 2)

Whether or  Not Candle Was Blown Out (Trial 3)

Whether or  Not Candle Was Blown Out (Trial 4)

Whether or  Not Candle Was Blown Out (Trial 5)

Majority (Majority is used instead of average because there cannot be a fraction of a blow)

No Mask (Control)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Dental Mask (Boomcare)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (2 blows)

Yes (1 blow)

Yes (1 blow) 

Cloth Mask (Bauer) 

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

KF94 Mask (P&B)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (1 blow)

Yes (4 blows)

Yes (1 blow)

KF80 (Wellkeeps)

No (5 blows)

No (5 blows)

No (5 blows)

No (5 blows)

No (5 blows)

No (5 blows)

KN95 Mask (Medsup)

No (5 blows)

No (5 blows)

No (5 blows)

No (5 blows)

No (5 blows)

No (5 blows

*Given the lack of dynamic data, I deemed the graphs inadequate to do, for they confused the reader rather than making the data easily decipherable.  

Experiment 2

- As I said in my introduction, I will be conducting the experiment twice, once with the inside of the mask facing up and once with the outside of the mask facing up.

Inside of Mask Facing Up

- Table: 

 

Amount of Water That Seeped Through Mask (Trial 1)

Amount of Water That Seeped Through Mask (Trial 2)

Amount of Water That Seeped Through Mask (Trial 3)

Average Amount of Water That Seeped Through Mask

No Mask (Control)

30ml

30ml

30ml

30ml

Dental Mask (Boomcare)

0ml

0ml

0ml

0ml

Cloth Mask (Bauer) 

0ml

0ml

0ml

0ml

KF94 Mask (P&B)

0ml

0ml

0ml

0ml

KF80 (Wellkeeps)

0ml

0ml

0ml

0ml

KN95 Mask (Medsup)

0ml

0ml

0ml

0ml

*Given the lack of dynamic data, I deemed the graphs inadequate to do, for they confused the reader rather than making the data easily decipherable. 

Outside of Mask Facing Up

- Table: 

 

Amount of Water That Seeped Through Mask (Trial 1)

Amount of Water That Seeped Through Mask (Trial 2)

Amount of Water That Seeped Through Mask (Trial 3)

Average Amount of Water That Seeped Through Mask

No Mask (Control)

30ml

30ml

30ml

30ml

Dental Mask (Boomcare)

0ml

0ml

0ml

0ml

Cloth Mask (Bauer) 

25ml

19ml

5ml

16.33ml

KF94 Mask (P&B)

0ml

0ml

0ml

0ml

KF80 (Wellkeeps)

0ml

0ml

0ml

0ml

KN95 Mask (Medsup)

0ml

0ml

0ml

0ml

*Given the lack of dynamic data, I deemed the graphs inadequate to do, for they confused the reader rather than making the data easily decipherable. 

Experiment 3 

- As I said in my introduction, I will be conducting this experiment at two different temperatures, which I later determined to be at -17°C and 0°C. 

At -17°C (February 15th, 2021) 

- Table:

 

Time Taken For Glasses to Fog up (Trial 1)

Time Taken For Glasses to Fog up (Trial 2)

Time Taken For Glasses to Fog up (Trial 3)

Average Time (Rounded to Two Decimal Places) 

No Mask (control) 

No Fog (∞)

No Fog (∞)

No Fog (∞)

No Fog (∞)

Dental Mask (Boomcare)

13s

7s

14s

11.33s

Cloth Mask (Bauer) 

4s

5s

5s

4.67s

KF94 Mask (P&B)

41s

85s

20s

48.67s

KF80 (Wellkeeps)

23s

46s

22s

30.33s

KN95 Mask (Medsup)

13s

20s

14s

15.67s

- Graphs:

Feb

At 0°C (February 24th, 2021) 

- Table:

 

Time Taken For Glasses to Fog up (Trial 1)

Time Taken For Glasses to Fog up (Trial 2)

Time Taken For Glasses to Fog up (Trial 3)

Average Time (Rounded to Two Decimal Places) 

No Mask (control) 

No Fog (∞)

No Fog (∞)

No Fog (∞)

No Fog (∞)

Dental Mask (Boomcare)

7s

6s

8s

7s

Cloth Mask (Bauer) 

12s

13s

7s

10.67s

KF94 Mask (P&B)

120s<

120s<

120s<

120s<

KF80 (Wellkeeps)

17s

22s

37s

25.33s

KN95 Mask (Medsup)

20s

15s

10s

15s

 

- Graphs: 

 

Analysis

Experiment 1

Analysis

  • Best Performing Masks in This Experiment: KF80 Mask, KN95 Mask

- All three masks took a majority of 1 blow to blow the candle out

- My hypothesis was partially correct - If several different masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) are worn while trying to blow out a candle, and whether or not the candle was blown out and the number of blows it took to do so is recorded, then the candle will not be blown out while wearing the KF94, KF80, and KN95 masks, because they have a larger number of layers and their texture is more stiff and rigid due to the inclusion of polypropylene nonwoven fabric.

- Only the KF94 mask did not fit my hypothesis

  • Poorer Performing Masks in This Experiment: Dental Mask, Cloth Mask, KF94 Mask

- Both masks could not blow the candle out in 5 blows

- My hypothesis was partially correct - The candle will be blown out while wearing the dental and cloth masks because they have a smaller number of layers and are more pliable. 

- Only the KF94 mask did not fit my hypothesis

- (Reasoning for both) The KF94 mask probably did not fit my hypothesis because, despite being 4-layered, all layers are made of the same material, nonwoven fabric. In order for a mask to properly filter air/particles, there needs to be some variation in the holes within the layers and the materials used for them, a design which the KF94 mask did not possess. 

Experiment 2

Analysis 

  • Best Performing Mask in This Experiment: Dental Mask (Both Sides), Cloth Mask (Inside of Mask Facing Up), KF94 Mask (Both Sides), KF80 Mask (Both Sides), KN95 Mask (Both Sides)

- All of the sides of these masks let no water through of the 30ml that was poured in

- My hypothesis was almost correct - If several different masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) are used to filter 30ml of water, and the amount of water that passes through the filter after 5 minutesis recorded, then all masks except for the cloth mask will prevent any water from passing through because they all have multiple layers of nonwoven fiber, a material that has some degree of liquid repellency. 

  • Poorer Performing Masks in This Experiment: Cloth Mask (Outside of Mask Facing Up)

- When the water was poured in from the outside, the cloth mask let in, on average, 16.33ml through

- My hypothesis was almost correct - If several different masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) are used to filter 30ml of water, and the amount of water that passes through the filter after 5 minutesis recorded, then all masks except for the cloth mask will prevent any water from passing through because they all have multiple layers of nonwoven fiber, a material that has some degree of liquid repellency. 

- (Reasoning for both) The cloth mask might have not let water pass when it was poured in from the outside because it had some type of waterproof coating on the outside; upon feeling either side of the cloth mask, the outside does seem to have a shinier texture which could indicate coating. 

Experiment 3 

Analysis 

  • Effect of temperature change on experiment results:

- For the majority of the masks, the time that it took for the wearer’s glasses to fog up to an extent that they needed to be taken off increased with the increase in temperature. 

- This is because fogging happens due to the difference in temperature between one’s breath and outside; breath has a relatively high temperature, and as the outside temperature increased, it decreased the difference between the two temperatures, making it harder for fog to appear.

- However, the trend and difference in time between the masks remained the same.

- changing temperature did not cause any experimental error and the higher the temperature, the less fogging appears on the glasses while wearing a mask. 

  • Best Performing Mask in This Experiment: KF94 Mask

- The KF94 mask took the longest to fog up to an extent that it affected visibility at -17°C, with an average of 48.67 seconds. At 0°C, it did not fog up to such an extent for the full 120 seconds (2 minutes)  

- My hypothesis was incorrect - If several different masks (Dental mask, Cloth Mask, KF94 Mask, KF80 Mask, KN95 Mask) are worn with glasses and the time it took for the glasses to fog up to an extent that the wearer has to take them off is recorded, then the KF80 mask will take the longest to do so because its wire is made of sheathed double iron core, a material that is ductile, and therefore can be bent to fit the wearer while maintainging its properties of strength. 

- The above results are likely because, although the KF80 used a robust and flexible wire, it might have been strong to an extent that it could not be bent to match the wearer's nose line, letting more air escape that the KF94, the mask with the less rigid yet more flexible wire.

  • Poorest Performing Mask in This Experiment: Dental Mask or Cloth Mask

- The dental mask took an average of 11.33 seconds at -17°C and 7 seconds at 0°C. 

- The cloth mask took an average of 4.67 seconds at -17°C and 10.67 seconds at 0°C. 

- It could be said that the cloth mask is the least successful because it took the shortest average amount of time to cause fogging at -17°C, the temperature which is more prone to causing fogging amongst the two. 

- My hypothesis was correct - The glasses will be taken off after the shortest time when wearing the cloth mask because it does not have any wire at all.

Conclusion

Conclusion

Please Read "Comparision Between My Experiment's Results and Other Papers" and "Ways to Improve My Project" later on in this section

Experiment 1

- The KF80 mask and the KN95 mask properly block air and are safe to wear

  A Good Mask Should: 

  - have 4 or more layers (for proper filtering)

  - include at least 1 layer of polypropylene fabric (for rigid structure) 

- The dental mask, cloth mask, and KF94 mask let the air pass through easily and are therefore unsafe to wear

  A Good Mask Should: 

  - use at least two different materials for layers (for proper filtering and to avoid from accumulating repetitive layers which have no effect)

- Ranked (From most successful to least) - based on yes/no and number of blows needed

1. KF80 or KN95

2. KF94 

3. Dental

4. Cloth

Experiment 2

- The dental mask, KF94 mask, KF80 mask, and KN95 mask do not let spit or other types of potentially harmful liquid pass through from either side and are safe to wear

  A Good Mask Should: 

  - include at least 1 layer of nonwoven fabric (for some degree of waterproof structure which prevents harmful liquids from entering/leaving) 

- The cloth mask lets a large portion of liquids pass through when they move from inside the mask to outside, which means that, although the cloth mask may prevent potentially harmful liquids from entering the wearer's nose or mouth, they let such liquids from the wearer's body escape and harm others; therefore, they are unsafe to wear

  A Good Mask Should: 

  - Avoid using polyester (ineffective filter) 

- Ranked (From most successful to least) 

1. Dental and KF94 and KF80 and KN95

2. Cloth

Experiment 3

- The KF94 mask took the longest time to cause fogging on glasses to an extent that they had to be taken off and is the most comfortable

  A Good Mask Should: 

  - use a polyproylene double wire (flexible yet rigid to an extent) 

- The cloth mask took the shortest time to cause fogging on glasses to an extent that they had to be taken off and is the least comfortable

  A Good Mask Should: 

- have a nose wire

- Ranked (From most successful to least) - data from experiment at -17°C since it is the condition more prone to causing fogging

1. KF94

2. KF80

3. KN95

4. Dental 

5. Cloth

Research (Durability+Cost Efficiency aka Financial Choice)

- Dental Mask: $0.40/1 - single use

- Cloth Mask: $12.00/1 - multiple use

- KF94 Mask: $1.40/1 - single use

- KF80 Mask: $2.00/1 - single use

- KN95 Mask: $1.25/1 - single use

- Ranked (From most successful to least) 

- For Single Use:

1. Dental

2. KN95

3. KF94

4. KF80

- For Multiple Use:

1. Cloth

Overall Rankings

- Safety 

  - KF80=KN95>KF94>Dental>Cloth

  - Dental=KF94=KF80=KN95>Cloth 

- Comfort

  - KF94>KF80>KN95>Dental>Cloth 

- Durability + Cost Efficiency 

  - Dental>KN95>KF94>KF80 (for single use) 

    or 

    Cloth (for multiple use) 

- Overall Ranking

 

Number of 1st Place Rankings

Number of 2nd Place Rankings

Number of 3rd Place Rankings

Number of 4th Place Rankings

Number of 5th Place Rankings

Dental Mask

2 (Safety, Durability+Cost Efficiency) 0 0 2 (Safety, Comfort) 0

Cloth Mask

0 (or 1 for Durability+Cost Efficiency)  0 0 0 3 (Safety, Safety, Comfort)

KF94 Mask

2 (Safety, Comfort) 0 2 (Safety, Durability+Cost Efficiency) 0 0

KF80 Mask

2 (Safety, Safety) 1 (Comfort) 0 1 (Durability+Cost Efficiency) 0

KN95 Mask

2 (Safety, Safety) 1 (Durability+Cost Efficiency)  1 (Comfort) 0 0
  • 1. Safety 
  • 2. Comfort
  • 3. Durability 
  • 4. Cost Efficiency

Using the chart (above) that I used to order the priority of the factors of a mask design, we can find that: 

- Amongst the masks tested and researched on in the experiment, the KF80 mask is the best mask. 

- The cloth mask is the least successful mask

- In order of most successful to least:

1. KF80 Mask

2. KN95 Mask

3. KF94 Mask

4. Dental Mask

5. Cloth Mask

Verdict on Each Mask

- KF80 (Welkeeps): Although the manufacturer may say it only filters 80% of particles, less than the other KN or KF masks, this mask excels in both air and fluid filtering aspects of safety. It is also comfortable, taking a long time to cause fogging on glasses to an extent that it obstructs vision. However, the main disadvantage is that it is more than twice as expensive as the dental mask. Nevertheless, I would recommend the Welkeeps KF80 mask to anyone; but due to it being made in Korea, the KN95 mask is a good alternative.

- KN95 (Medsup Canada): Although the tight fit of the mask may take away from being comfortable, the KN95 mask is equally effective in filtering air and water droplets as the KF80 mask; additonally, it is cheaper than the KF80. I would recommend the Medsup KN95 mask to anyone, especially since it will be more easier to find than the KF80 mask. 

- KF94 (P&B): Despite having said to filter 94% of particles, the KF94 mask is only effective when filtering water. Nevertheless, it possesses an advantage in comfort; being the mask which took the longest time to cause fogging on glasses that obstructs visibility. It is about a dollar more expensive than dental masks. I would recommend the P&B KF94 mask to anyone, and although a KF80 or KN95 mask is generally better, the KF94 mask might be better for longer periods of use, since, due to the lack of fogging, it does not have to be adjusted as often. 

- Dental Mask (Boomcare): Although the dental mask is inexpensive, it comes at the cost of safety and comfort. In terms of safety, the dental mask can prevent water droplets from passing through, but is ineffective when it comes to filtering air. Furthermore, it causes frequent fogging on glasses, making the user need to touch their face to adjust it. I would only recommend the Boomcare dental mask to those who want additonal protection when outdoors, and if they cannot afford the KF or KN masks.  

- Cloth Mask (Bauer): This mask does provide the wearer with any advantages; it lets air and water droplets pass easily through, frequently causes fogging, and is expensive. It is also disappointing that the cloth mask has a poor performance, although Bauer, as a sporting goods company, should provide one of the better masks to protect athletes from the risk of infection they are exposed to during excersise. I would not recommend the Bauer cloth mask, especially to athletes. 

 

Comparison Between My Experiment's Results and Other Papers

KF80 mask was the best performing; Cloth mask was the poorest performing

Coronavirus Face Masks & Protection FAQs - Johns Hopkins Medicine

- The KF80 mask fits what the article defines as characteristics of a good mask

  - able to be worn without frequent adjustment - takes a long time to cause fogging

  - has multiple layers of fabric - has 4 layers

  - flexible but strong wire - wire stopped air from escaping and condensing on the glasses while wearing the KF80 mask

- The article says that a cloth mask should be made with densley woven cotton fabrics

  - the Bauer cloth mask used in my experiment was composed of polyester, so this might be a reason for its poor performance

- Similar to my findings 

A User's Guide To Masks: What's Best At Protecting Others (And Yourself) - NPR (National Public Radio - US) 

- the article says that both cotton and polyester are effective materials for cloth masks

  - the cloth mask tested in my experiment was made of polyester but still performed poorly

- article says that multiple layers are effective

  - KF80, and all masks other than cloth masks had multiple layers

- article says polyproylene is a good filter material due to its electrostatic charge 

  - KF80 mask had a polypropylene filter, and another layer made of it

- article says masks with folds are effective

  - only the dental mask had folds and it performed second poorest

- article says dental masks are effective at stopping particles from escaping the wearer, but not neccessarily when protecting them from incoming ones

  - the dental mask let air escape easily from the wearer, resulting in the blowing out of the candle

- Overall, similar to my findings, with minor differences

Filtration Efficiencies of Nanoscale Aerosol by Cloth Mask Materials Used to Slow the Spread of SARS-CoV‑2 - ACS Nano (American Peer-Review Journal)

- in this experiment, where types of cloth masks, neck gaiters, and N95 masks were tested, the N95 performed the best

  - Excluding the KF masks, for they were not tested in ACS Nano's exepriment, the KN95 mask, the Chinese counterpart of the N95 performed the best

- Similar to my findings

KMS (Journal of Korean Medical Science) - Linked to PMC (US National Library of Medicine National Institutes of Health) - What Type of Face Mask Is Appropriate for Everyone-Mask-Wearing Policy amidst COVID-19 Pandemic?

- In this experiment, it was conluded that HEPA masks (KN or KF masks) enforced safety at the cost of comfort

  - In terms of causing fogging on glasses, which was the main method of how I judged comfort, the KN and KF masks achieved either 1st or 2nd in rank of best performing to least performing

- Contradicts with my findings

AAAS (American Association for the Advancement of Science) - Low-cost measurement of face mask efficacy for filtering expelled droplets during speech

- In this experiment, the rank of best performing to least performing mask were: N95, dental, cloth, gaiter/bandanna 

  - Excluding the KF masks which were not tested in AAAS's experiment, the ranking in my experiment was: N95, dental, cloth

Similar to my findings

PMC (US National Library of Medicine National Institutes of Health) - Effectiveness of Surgical and Cotton Masks in Blocking SARS–CoV-2: A Controlled Comparison in 4 Patients

- In this experiment, it was found that neither cloth or dental mask was effective as N95 masks against Covid-19

  - neither cloth mask or dental mask performed higher than N95

Similar to my findings

Overall:

My experiments' results are similar to many other professional sources from across the world; thus, they are reliable

Ways to Improve My Project

1. Although the Bauer cloth mask displayed poor performance, there are other variations of cloth masks with more than 1 layer or polypropylene filters that can be tested; this could be an extended/additonal study on my project

2. I judged the masks based on safety, comfort, durability, and cost efficency. However, I could include factors such as fit (size) or conduct opinion-based surveys on the comfort of the mask; admittedly, this would not be possible due to the pandemic

- if I did the survey:

  - I would have a participant wear a type of mask for a day, and then ask them to fill out a (Google) form which could ask them to rank the comfortability of the mask on a scale of 1 to 10 or answer yes/no questions on whether or not the mask slipped down while talking, whether it was hard to breath, etc. 

3. I could adjust experiments 1 and 2 to have stronger quantitative data 

- Experiment 1 (data is not specific enough - yes/no)

  - I could attach the mask as a cover to a hair drier or some strong type of blowing device, that can blow a candle when there isn't any covering

    - I could then try blowing the candle out again using the covered hair drier/blowing device and record if the candle is blown out

    - although this does not make my data more specific, it makes my experiment much easier to control, in terms of blwoing strength 

- Experiment 2 (there is little variation between data - almost all, other than cloth masks, let 0ml pass through of the 30ml)

  - I could try testing the individual layers of the masks, rather than testing the mask as a whole

    - The water would seep through much more easily, and give me variation in data

  - I could also try spraying one side of the mask with water, and measuring how much water seeps through and also recording visual observations

    - Another variation could be dropping food colouring on the mask and observing how much shows up on the other side

4. I could create an experiment for durability and cost effiency, factors which I analyzed through research instead of experimenting

- Initially, I did try to make an experiment for durability and cost efficency by washing the masks in the washing machine, but they broke apart and got stuck in the machine*

  - Instead, I could handwash them and assess the physical damage done; however, this would have to be qualitative and might not be strong data 

5. I could add more participants in experiment 3, rather than solely my mother; again, this would not be possible due to the pandemic

6. I could re-do schlieren imaging*; this would allow me to incoporate a complicated experiment, acting as support for other experiments

- Sclieren Imaging is a photography technique used to view fluids of different density (viewing movement of air)

- I initially tried this*, but I did not have the proper equipment

- If I gain these equipment, notably a high resolution camera and large concave mirror, there is a high chance I might be able to make it work

7. I could test bandannas or neck gaiters to see if they really were ineffective, since most of the articles I read deemed them as one of the worst performing face-coverings

8. I could also test the N95, in order to see if there is some difference in performance between it and its Chinese counterpart, KN95, which I tested in my experiment

*refer to logbook and the "failed experiments" section

Application

Real World Application

Experiment 1

- The less air that passes through a mask, the less potentially harmful particles enter or escape the body, keeping both the wearer and those around them safe

Experiment 2

- The less amount of liquids that can pass through a mask, the less potentially harmful fluids enter or escape the body, similarly keeping both the wearer and those around them safe

Experiment 3

- The less fogging, the less the wearer has to touch their face to adjust their glasses or wipe them, enforcing a safer usage of masks

Overall

- Potential to be used in developing other filters, such as water filters used in piping and air filters used in washing machines or air conditioners 

- Many people rely on homemade cloth masks - debunks this belief

- Provides people with what type of mask they should be using:

  - a KF80 mask 

  - but since KF80 masks are only widely available in South Korea and Asia, I also made a design for what the most ideal mask would look like.

  - an ideal mask would have the follow criteria:

    - have 4 or more layers

    - include at least 1 layer of polypropylene fabric

    - use at least two different materials for layers

    - include at least 1 layer of nonwoven fabric

    - no polyester

    - use a polyproylene double wire

  • Non-medical
  • Materials: Nonwoven Fabric, Polypropylene Nonwoven Fabric (No Polyester)
  • Layer Number: 4 - Nonwoven Fabric + Polypropylene Nonwoven Fabric + Polypropylene Nonwoven Fabric + Nonwoven Fabric 
  • Single use recommended
  • Wire Material: Polypropylene Double Wire
  • Estimated Price: <$2.00/1 

Sources Of Error

Experimental Errors:

Experiment 1

- The strength with how I blow each time 

Experiment 2

- Minimum time errors - caused by a possible slight difference in the time it took for me to pour the water on the mask and then press the timer 

- Discovered that if mask was wet, it let water through eaiser (error was corrected) 

- Speed with how water was poured on top of the mask

Experiment 3

- Some fogging could have accumulated on glasses when wearer stepped outside, before starting the experiment

- Experiment was only conducted based on 1 person's opinion 

Failed Experiments: 

- Schlieren Imaging: 

  - Schlieren imaging is a technique involving optics which allows one to visulaize heat waves

  - It needs a complicated setup, involving high-tech materials

  - Although there were some sources showing ways to do schlieren imaging using low-tech materials, ultimately, I did not have the tools to successfully pull such an experiment off

  - Mine:

  - What it should look like:

- Earlier Variations of Experiment 1:

  - Initially, I tried blowing out the candle while wearing a mask 1m away from it. I would step closer to the candle by 3cm until I could blow it out

  - But, candles need to be close to the mouse in order to be blown out, so I had to scrap this experiment and modify it

- Durability Experiment:

  - Initially, I also had an experiment for durability, where I put the mask in a washing machine and assessed the dammage done to it

  - However, the masks meant for single use caused unprecedented difficulties by breaking apart and getting stuck in the machine, forcing me to replace the experiment with a research into the durability and cost efficiency of each mask instead. 

Citations

Works Cited

“About Nonwovens.” INDA, Association of the Nonwoven Fabrics Industry, 17 Dec. 2019, www.inda.org/about-nonwovens/.

“ARCHIVED: Coronavirus Disease (COVID-19): Summary of Assumptions.” Canada.ca, Government of Canada / Gouvernement Du Canada, 24 Aug. 2020, www.canada.ca/en/public-health/services/diseases/2019-novel-coronavirus-infection/health-professionals/assumptions.html.

Bae, Seongman, et al. “Effectiveness of Surgical and Cotton Masks in Blocking SARS-CoV-2: A Controlled Comparison in 4 Patients.” Annals of Internal Medicine, American College of Physicians, 7 July 2020, www.ncbi.nlm.nih.gov/pmc/articles/PMC7153751/.

Bult, Laura, et al. What Face Masks Actually Do against Coronavirus. Vox, Vox, 22 Apr. 2020, www.youtube.com/watch?v=P27HRClMf2U.

Fischer, Emma P., et al. “Low-Cost Measurement of Face Mask Efficacy for Filtering Expelled Droplets during Speech.” Science Advances, American Association for the Advancement of Science, 1 Sept. 2020, advances.sciencemag.org/content/6/36/eabd3083.

Godoy, Maria. “A User's Guide To Masks: What's Best At Protecting Others (And Yourself).” NPR, NPR, 1 July 2020, www.npr.org/sections/goatsandsoda/2020/07/01/880621610/a-users-guide-to-masks-what-s-best-at-protecting-others-and-yourself.

Hindle, Colin. Polypropylene (PP), British Plastics Federation, www.bpf.co.uk/plastipedia/polymers/pp.aspx.

“Installation Lines Melt Blown - ENTECH Srl.” ENTECH S.R.L. EXTRUSION NONWOVENS TECHNOLOGIES, Entech, www.entechsrl.com/sectors/melt-blown/#:~:text=Basic characteristics of the Melt,as 10 to 15 µm.

"Iron." Chemicool Periodic Table. Chemicool.com. 06 Oct. 2012. Web. 3/3/2021
<https://www.chemicool.com/elements/iron.html>.

Kim, Mi Na. “What Type of Face Mask Is Appropriate for Everyone-Mask-Wearing Policy amidst COVID-19 Pandemic?” Journal of Korean Medical Science, The Korean Academy of Medical Sciences, 25 May 2020, www.ncbi.nlm.nih.gov/pmc/articles/PMC7246185/.

Labos, Christopher. “What Makes a Good Mask? Let's Uncover the Facts.” Office for Science and Society, Mcgill , 17 July 2020, www.mcgill.ca/oss/article/covid-19-health/what-makes-good-mask-lets-uncover-facts.

Maragakis, Lisa Lockerd. “Coronavirus Face Masks & Protection FAQs.” Coronavirus Face Masks: Types & When to Use | Johns Hopkins Medicine, John Hopkins Medicine, 29 Jan. 2021, www.hopkinsmedicine.org/health/conditions-and-diseases/coronavirus/coronavirus-face-masks-what-you-need-to-know.

MasterClass. “Polyester Fabric Guide: Explore the Look and Feel of Polyester - 2021.” MasterClass, MasterClass, 9 Nov. 2020, www.masterclass.com/articles/polyester-fabric-guide#what-are-the-characteristics-of-polyester-fabric.

Zangmeister, Christopher D., et al. “Filtration Efficiencies of Nanoscale Aerosol by Cloth Mask Materials Used to Slow the Spread of SARS-CoV-2.” ACS Nano, vol. 14, no. 7, 2020, pp. 9188–9200., doi:10.1021/acsnano.0c05025.

Acknowledgement

Thank you to:

- My mother for her participation in one of my experiments

- Webber Academy for providing me with the opportunity to pursue my interests even during these difficults times

- Ms. Grelowski, Ms. Diaz, and Ms. Gierus for coordinating the senior school science fair

- Dio for his adept advice in the organization and presenation of my project