The following literature will serve to evaluate design considerations for different types of masks, considering the surge of designs by many communities. Some previous studies have evaluated the effectiveness of different homemade masks. While "none of these are as effective as a commercially designed face mask", they all offer some protection when other options are not available. It could be argued that a cloth face mask design can be effective and therefore a recommended measure as long as the design is good and hygiene training is in place for all users.
Related works[edit | edit source]
Examine what sort of work has been done on the topic and identify new possible issues or any recent research that has brought up issues about past assumptions.
Effectiveness[edit | edit source]
- Measurements in relation to graded masks (N95, N100). Results from literature still have a wide variety of ranges (10%-70%) for face masks, which serves to understand that not all DIY masks are made and wore the same.
- DIY evaluation (testing in experimental conditions and real use feedback)
- Adaptation to different face shapes and sizes: designs need to be adaptable or parametric.
- Good practices of making and using masks must be reproduced in order for masks to make sense.
Filter materials[edit | edit source]
- Industrial filters: some DIY designs are currently considering the use of HEPA filters. Consider questions such as the cost and availability of these filters in your location for sustained use by healthcare workers or the general population.
- Tea towel (tea cloth) or fabric layers: Some studies corroborate the feasibility of using layered fabric to make masks. Different considerations must be used when designing cloth masks.
- EVA filter: Some DIY projects have used EVA as a filter, due to it being a cheap and widely-available material.
- PLA or other 3D-printed materials: a current discussion has been raised around the porous quality of 3D-printed masks, which raises the question of whether they are the best material for home-made masks.
Cost and appropriateness[edit | edit source]
- Availability of materials: how easy are the materials easy to find? Are they found everywhere in the world?
- Overall cost: How much does it cost to reproduce.
- Easiness of documentation: are these masks fully reproducible? Are there variations in how people will make them?
- Lack of digital fabrication tools in certain areas can limit how these masks are made.
Hygiene[edit | edit source]
- Will they be reused/disinfected? Heat, UV light, water, soap, alcohol.
- Availability of replacement filters or masks.
- Microplastics from 3D printing having an effect on health due to a sustained use.
- Where does the humidity from the wearer's mouth go.
Comfort and ergonomics[edit | edit source]
- People will wear a mask for longer if they feel comfortable with it.
- More protective masks are less comfortable to breathe through.
DIY mask design and testing[edit | edit source]
Shaffer, R., Krah Cichowicz, J., Chew, G., & Hsu, J. (2018). Non-occupational Uses of Respiratory Protection – What Public Health Organizations and Users Need to Know. NIOSH Science Blog. Retrieved March 20, 2021, from https://blogs.cdc.gov/niosh-science-blog/2018/01/04/respirators-public-use/
- Research Questions you're answering:
- Summary notes from article/source:
- Masks are likely to be worn incorrectly: independently of the mask used, a great part of the effort must be put into training the general population on the correct usage of masks.
- Fit tests must be performed for each user.
MacIntyre CR, Seale H, Dung TC, et al. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ Open 2015;5:e006577. doi: 10.1136/bmjopen-2014-006577
- This study recommends against the use of cloth masks.
- "Penetration of cloth masks by particles was almost 97% and medical masks 44%."
Mask assesment[edit | edit source]
Xiao J, Shiu EYC, Gao H, Wong JW, Fong MW, Ryu S, et al. Nonpharmaceutical measures for pandemic influenza in nonhealthcare settings—personal protective and environmental measures. Emerg Infect Dis. 2020 March 24. https://doi.org/10.3201/eid2605.190994
- Medical masks: "There is limited evidence for their effectiveness in preventing influenza virus transmission either when worn by the infected person for source control or when worn by uninfected persons to reduce exposure (...)"
- "Proper use of face masks is essential because improper use might increase the risk for transmission."
Shakya, K., Noyes, A., Kallin, R. et al. Evaluating the efficacy of cloth facemasks in reducing particulate matter exposure. J Expo Sci Environ Epidemiol 27, 352–357 (2017). https://doi.org/10.1038/jes.2016.42
"When the cloth masks were tested against lab-generated whole diesel particles, the filtration efficiency for three particle sizes (30, 100, and 500 nm) ranged from 15% to 57%."
This is another way to document your findings: Synthesis matrix. You can use your own method as long as you can identify the knowledge gaps that exist on the subject.
Conclusion[edit | edit source]
The conclusions must be related to the study's objectives and avoid statements not sufficiently supported by the available data. In addition, they have to be clear and concise.
Bibliography[edit | edit source]
- Creswell, J. W. (2009). Research design: Qualitative, quantitative, and mixed methods approaches (3rd ed.). Sage Publications, Inc.
- Shaffer, R., Krah Cichowicz, J., Chew, G., & Hsu, J. (2018). Non-occupational Uses of Respiratory Protection – What Public Health Organizations and Users Need to Know. NIOSH Science Blog. Retrieved March 20, 2021, from https://blogs.cdc.gov/niosh-science-blog/2018/01/04/respirators-public-use/
- MacIntyre CR, Seale H, Dung TC, et al. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ Open 2015;5:e006577. doi: 10.1136/bmjopen-2014-006577
- Jung, H., Kim, J., Lee, S., Lee, J., Kim, J., Tsai, P., & Yoon, C. (2014). Comparison of filtration efficiency and pressure drop in anti-yellow sand masks, quarantine masks, medical masks, general masks, and handkerchiefs. Aerosol Air Qual Res, 14(14), 991-1002. Retrieved from: http://aaqr.org/files/article/668/36_AAQR-13-06-OA-0201_991-1002.pdf
Appendices[edit | edit source]
