
This mask design fits very well. It is double layer cotton, with a space between for filter material. The nose bridge has a metal insert for forming around your nose. Straps go around your neck and head. Photo1 by Don Tai
These face masks are nowhere near as good a filter as an N95. The material to make an N95 is quite expensive and specialized. The N95 also needs to be air tight. N95 masks need to be certified. Wearers also need training and a fit test. No cloth mask, nor any surgical style mask meets this criteria. If you work in a hospital or are that close to a person with the virus, use an N95. This study Simple Respiratory Protection—Evaluation of the Filtration Performance of Cloth Masks and CommonFabric Materials Against 20–1000 nm Size Particles shows that these DIY cloth masks are nowhere near as good as the N95. The N95 standard is not only much more expensive, but if in high demand, such as a pandemic, will be difficult to obtain and may deprive health care workers of necessary stock.
The fabric materials tested in our study might also be expected to provide marginal levels of respiratory protection for 20–1000 nm aerosols (droplet nuclei). Fabric materials may provide respiratory protection levels (i.e. total inward leakage) similar to the levels obtained using some surgical masks,which have been measured to be, 10 (Oberg and Brosseau, 2008). Thus, the use of improvised fabric materials may be of some value compared to no protection at all when respirators are not available. Moreover, fabric materials would not suffer from limited supplies unlike respirators and surgical masks for emergency protection….
The penetration levels obtained for fabric materials against both polydisperse and monodisperse aerosols were much higher than the value for the control N95 respirator filter media but were in the range found for some surgical masks in previous studies.

This mask design fits very well. It is double layer cotton, with a space between for filter material. The nose bridge has a metal insert for forming around your nose. Straps go around your neck and head. Photo1 by Don Tai

This mask design fits very well. It is double layer cotton, with a space between for filter material. The nose bridge has a metal insert for forming around your nose. Straps go around your neck and head. Photo2 by Don Tai

This mask design fits very well. It is double layer cotton, with a space between for filter material. The nose bridge has a metal insert for forming around your nose. Straps go around your neck and head. Photo3 by Don Tai

Face mask nose bridge wire is originally 5″ long, ends bent back, and kinked in the middle. photo by Don Tai
I don’t really know the type of wire I’m using, but it is magnetic. The diameter is 1/16″ 0.0625″, as far as I can tell. This would be close to a 14 gauge 0.0641″ wire. The ends are turn inward into itself so the ends are no longer sharp. The wire is laid flat and then kinked in the middle. This kink acts as an aid once you put it into the sewn channel in the mask, providing a visual cue as to the middle of the nose bridge and therefore the mask. The nose bridge wire can then be custom bent to the person’s face contour for a custom fit.
Disinfecting clothing
This article has tips on how to disinfect clothing. Interestingly it recommends white cotton because it can withstand the hard disinfecting chemicals.
Normal laundry procedures should be using hot water (100 degrees F. or above with 140 degrees F being optimal), a disinfectant product following product directions, and finally, a high heat machine drying cycle…
When someone is ill, opt for white 100 percent cotton sheets. Why? They may be boring but are easy to disinfect with hot water. Sheets that are bright colors and a synthetic blend cannot stand up to the rigors of disinfecting chemicals.
US CDC disinfection information also recommends diluted bleach.
Disinfectant: 5tbsp bleach/4L water
More simply, to kill the virus, simply wash with soap and water. This breaks down the outer lipid/fatty layer of the virus and it does. This is simpler and less caustic than bleach or other disinfectant.
Improvements:
Make the inner layer shorter at the ends, edges sewn down to the wrong sides. This allows the outer layer’s edge to be folded over for the elastic, but allow extra filtering medium to be inserted into the middle.
Serge the outer layer’s ends. This reduces the bulk when you fold it over for the elastic.
Filter Material
Non-woven polypropylene, the material used in reusable shopping bags, has come up many times. This video 2’35” quotes a Dr Jorhay Zuniga, from Chile, on the Open Source COVID19 Medical Supplies thread, as saying the material will block 96.4% of 1 micron particles and 89.5% effective for 0.2 microns.
Jorge Zuniga
March 21 at 9:05 PM
NanoHack
NanoHack Mask is a last resort device with the purpose of offering protection from airborne particles and prevent spreading liquid contaminating the airways. Published data1 has shown that the filtration materials used by NanoHack (polypropylene, the same material used in surgical masks) achieves a filtration efficiency of 96.4% for microorganisms of 1 micron and 89.5% for microorganisms of 0.02 microns1.1. Anna Davies, et al. Testing the Efficacy of Homemade Masks: Would They Protect in an Influenza Pandemic? Disaster Medicine and Public Health Preparedness, Available on CJO 2013 doi:10.1017/dmp.2013.43
Fit tested Sewn Mask
Here’s a Youtube vid about a doc who used a University of Florida design with Halyard H600 material. The nose bridge is 5″ of 16 ga wire. Interesting testing procedure.
Addendum 2020 Mar 27 A Sewing Army, Making Masks for America
But a 2008 study on the use of both commercial and home-made masks by the general public to ward off influenza, published in the journal PLoS, found that “all types of masks reduced aerosol exposure”.
Although home-made masks performed less well, “any type of general mask use is likely to decrease viral exposure and infection risk on a population level, in spite of imperfect fit and imperfect adherence, personal respirators providing most protection,” the researchers from the Dutch National Institute for Public Health and the Environment concluded. source
face mask pattern from craftpassion.com
Fogging Glasses
We had an issue with fogging of glasses. This was greatly minimized when I added a metal wire to the nose piece, which greatly limits the air escaping from your exhale. How to stop a face mask fogging up your glasses
A flexible “nose”
Some masks come with a metal nose clip that allows the wearer to limit the amount of moisture that comes in or out of the mask. If you’re sewing home-made masks, you can use flexible objects like hair grips, paper clips or pipe cleaners to create a fitted “nose”.
HK Mask is a reusable cloth mask with a disposable middle layer filter. It was invented by Dr. K. Kwong during the outbreak of COVID-19 in early 2020.
The design of HK Mask is referred by that of 3-layer surgical mask in the market. The HK Mask is composited with a disposable middle layer filter which is sandwiched by a cloth mask as the outer and inner layers. There are a number of material chosen for the middle layer filter ranging from Kitchen Towel Paper to Nanofilter.
The filtration efficiency of a piece of kitchen towel paper is close to that of N70. The mask can be safely used after replacing a new middle layer filter to a cleaning and sterilizing the inner and outer layer cloth…
The FILTER can be two pieces of pocket tissue paper or one piece of kitchen tissue paper.
The mask can be made of any fabrics, but the thinner the better.
This mask design uses an inner pocket where you can add a filter layer. The filter layer sticks out the bottom 2 corners as well as the top. It has both ear elastics as well as ties at the back of the head and neck. The advantage is that the filter material is rectangular and needs no cutting nor sewing.
CuMask+, from the Hong Kong government
This mask design has a built-in filter that is washable 60 times, after which you can replace the filter. The filter material has woven copper that claims to attract small particles. The HK government will be providing a mask for each resident for free. This is a great idea, and should reduce the demand for single use surgical masks.

The CUMask+ from Hong Kong, is a washable, reusable face mask, provided free of charge to all HK residents. The filter material is washable, has copper fibers that attract small particles, and is replaceable. Great ideas from HK, and good government policy. Demand for single use surgical and N95 masks will be markedly reduced. Photo from SCMP.
HK CuMask Review. There are other reviews but are in Cantonese. One issue that came up with all reviews is that the mask has no nose bridge, leaving two open areas on either side of the nose. This lets in air when breathing, thus reduces the efficacy but eases breathing capability.
What we’ve learned after making 167,000 masks!: Uses the craftpassion pattern for a fitted mask
A different fitted mask design by Jesse Killion
Government Guidance Articles
- EU: Austria: Austria, in a shift, requires mask-wearing in supermarkets to cut pandemic’s spread
- Czech Republic: Czechs get to work making masks after government decree: Slovakia and the Czech Republic require masks in public
“The Czech Republic is one of the few in Europe that has significantly slowed down the spread of the virus,” the narrator says. “The main difference is that everyone who has to leave their house has to wear a mask…
“The students are making hundreds and hundreds of masks,” said Alice Klouzkova, an assistant and teacher at the academy’s fashion design studio. “Most of them have sewing machines at home and are happy to work with their hands. It’s important that the material is made with 100% cotton so it can be sterilised.””
- Germany, Jena: In ‘Big Adjustment,’ Some European Countries Push For Residents To Wear Masks
German Chancellor Angela Merkel said Wednesday that masks should be worn on public transport and in shops as Germany cautiously begins to ease curbs imposed to halt contagion of the coronavirus pandemic.
“It is recommended that masks be used in public transport and while shopping,” Merkel told journalists after talks with regional leaders from Germany’s 16 states.
Jena, a city in eastern Germany, announced this week that within several days it will be compulsory to wear a mask in supermarkets and on public transit — but the German government as a whole has issued no such recommendation.
- Germany: Germany recommends face masks in shops and public transport
- Germany:
New rules have come into force legally requiring most people in Germany to wear face masks on public transport, long-distance trains and in shops…
A poll by the Kantar market research institute found that acceptance for mask wearing was extremely high, with 97% of those asked saying they supported the rule and recognised the importance of keeping it to help tackle coronavirus.
- Czech Republic, Slovakia and Bosnia-Herzegovina: Should all Americans be wearing face masks to protect against coronavirus? Trump, Fauci are closer to saying yes: The Czech Republic, Slovakia and Bosnia-Herzegovina now require people to wear masks in public, while Austria requires their use in grocery stores.
- Italy, Lombardi: Lombardy insists on face masks outside homes to stop Covid-19: Extremely late, after so much carnage, but better than never
Authorities in Lombardy, the Italian region worst affected by coronavirus, have introduced a law obliging citizens to wear face masks when they go outside…
Lombardy’s president, Attilio Fontana, announcing the new law there, said people should “cover their mouths and noses” with a simple scarf, saying it would help “prevent you from spreading the virus if you happen to be a carrier”…
The Lombardy law will be in place at least until 13 April, when Italy’s lockdown is due to expire.
- France: Abrupt reversals on face mask policy raise new questions
France’s Académie Nationale de Médecine (Academy of Medicine) announced Friday that a mask should be compulsory during outings both during and after the current lockdown.
- US: California Department of Public Health: page does not respond
City of San Diego:
4/2 Press Conference Updates:Mandatory non-medical-grade masks to be worn by workers at businesses that interact with the public including grocery stores, pharmacies, and gas stations source
The order will make it mandatory for businesses that interact with the public to use cloth face coverings for their employees starting Saturday; that includes grocery stores, pharmacies, gas stations and restaurants…
The general public will not be required to wear facial coverings but will be urged to do so when out in public for essential activities, according to the new order.
Medical-grade masks should not be used but homemade masks, bandanas, scarves and neck gaiters are acceptable since the items can be washed and reused. source
- Los Angeles: City of L.A. guidance on wearing face coverings in public
In response to the COVID-19 pandemic, the City of Los Angeles has issued new guidance to L.A. residents on the importance of wearing face coverings in public…
Early data suggests that many who are infected with COVID-19 are not symptomatic, which is why we recommend all members of the public wear cloth face coverings when leaving the house for essential activities.
- New York City: Face Coverings:Frequently Asked Questions
The New York City Department of Health and Mental Hygiene recommends that all New Yorkers wear a face covering when outside of their hometo help stop the spread ofcoronavirus disease 2019(COVID-19).
- New York State: New York Orders Residents to Wear Masks in Public
Imposing a stricter measure to control the spread of the coronavirus, Gov. Andrew M. Cuomo said on Wednesday that he would start requiring people in New York to wear masks or face coverings in public whenever social distancing was not possible.
The order will take effect on Friday and will apply to people who are unable to keep six feet away from others in public settings, such as on a bus or subway, on a crowded sidewalk or inside a grocery store.
- Maryland: Marylanders are required to wear a face mask. How do you make one? And other frequently asked mask questions.
Officials in Maryland will begin enforcing the U.S. Centers for Disease Control and Prevention’s recent recommendation that people wear cloth face coverings over their noses and mouths when they enter public places such as grocery stores to slow the spread of the new coronavirus.
- New Jersey: New Jersey orders residents to wear masks in grocery stores, N.J.’s new coronavirus rules for grocery shopping. Masks, store limits, everything you need to know.
- Pennsylvania: Order of the Secretary of the Pennsylvania Department of Health Directing Public Health Safety Measures for Businesses Permitted to Maintain In-person Operations
B.In addition to the above, the following measures apply to businesses, other than health care providers, that serve the public within a building or a defined area:…
(6)require all customers to wear masks while on premises,and deny entry to individuals not wearing masks, unless the business is providing medication, medical supplies, or food, in which case the business must provide alternative methods of pick-up or delivery of such goods;however, individuals who cannot wear a mask due to a medical condition(including children under the age of 2 years per CDC guidance)may enter the premises and are not required to provide documentation of such medical condition;
- Illinois: Guidance on the Use of Masks by the General Public
All Illinoisans should wear as mask or face covering when they must leave their home or report to work for essential operations and they either cannot or it is impractical to maintain 6 feet of physical distance between themselves and others. Examples include:
- Shopping at essential businesses, like grocery stores or pharmacies,
- Picking up food from the drive thru or curbside pickup,
- While visiting your health care provider,
- Traveling on public transportation,
- Interacting with customers, clients, or coworkers at essential businesses,
- Performing essential services for state and local government agencies, such as laboratory testing, where close interactions with other people are unavoidable, and
- When feeling sick, coughing, or sneezing.
Probably the best press release of any government body so far. Clear information, with examples, and the reasoning behind the requirement.
- Canada: Recommendation Regarding the Use of Cloth Face Coverings, Especially in Areas of Significant Community-Based Transmission
In light of this new evidence, CDC recommends wearing cloth face coverings in public settings where other social distancing measures are difficult to maintain (e.g., grocery stores and pharmacies) especially in areas of significant community-based transmission.
- Canada: Tam offers new advice: wear a non-medical mask when shopping or using public transit: Finally, only after the WHO and CDC
- Canada’s top doctor says non-medical masks can help stop the spread of COVID-19
- Canada’s medical chief finally tells public that masks can help prevent Covid-19 spreading
Therefore, we will no longer discourage people from wearing masks . Wearing a mask may help to protect others, in case you have the virus but don’t know it. This is so that you keep your droplets to yourself – when you sneeze or speak or cough. It can also protect yourself a little better, especially if you are elderly, or vulnerable because of pre-existing health conditions.
Prime Minister Lee, in his address to nation on 3 Apr on COVID-19 situation- WHO: World Health Organisation reverses course, now supports wearing face masks in public
- Singapore: When should I wear a mask?
Wear a mask if you are out and in close contact with others. Here’s where to collect your reusable mask- Singapore: Singapore makes face masks compulsory as coronavirus infections surge to 3,252 amid mass testing of migrant workers
- Israel: Israelis required to wear face masks when out in public
Israelis are required to wear faces masks when venturing outside in accordance with a new Health Ministry directive that came into effect on Sunday morning. The measure was approved by the government this past week.
Under the new rules, masks must be worn when leaving home and should cover the nose and the mouth…
The masks can be homemade, makeshift, or bought, according to the authorities. The order had previously been issued as a recommendation.
- Turkey: Turkey Orders All Citizens to Wear Masks as Infections Rise
- India: New Delhi, Mumbai, Uttar Pradash Major Indian cities make mask-wearing compulsory amid virus fears
General Articles
- More Americans Should Probably Wear Masks for Protection
- Chinese scientist advises people in Europe, US to wear face masks in public
- Coronavirus: should I make my own mask? How home-made ones may help stop Covid-19 spread
- US starts to change its thinking on wearing protective masks
- End Canada’s face mask misdirection. It is preposterous
- COVID-19: WHY WE SHOULD ALL WEAR MASKS — THERE IS NEW SCIENTIFIC RATIONALE
Absence of evidence (of protection) is not evidence of absence…
Given that the upper respiratory tract is the major site for SARS-Cov-2 entry into human tissues, wearing simple face masks which exert a barrier function that blocks those big projectile droplets that land in the nose or throat may substantially reduce the production rate R
- A collection of face mask articles in Google Docs, which might be busy
- To mask or not to mask: WHO makes U-turn while US, Singapore abandon pandemic advice and tell citizens to start wearing masks
- Is A Homemade Mask Effective? And What’s The Best Way To Wear One?
- Sew much demand: Suddenly, homemade masks are a booming cottage industry
- White House Debates How Far to Go on Face Mask Guidelines
- Coronavirus FAQs: Is A Homemade Mask Effective? And What’s The Best Way To Wear One?
- Bow ties to face masks: German firms shift gears in coronavirus crisis
- Calls grow for Germany-wide use of face masks
- Theresa Tam issues new guidance on the wearing of masks, so here’s what you need to know
The CDC recommendation came after new evidence that there is significant transmission by people not showing any symptoms of COVID-19 – as many as 25 per cent of those infected, CDC director Robert Redfield told Atlanta’s WABE 90.1 FM radio station in an interview last week. As well, he said those who do become symptomatic appear to shed the virus “probably up to 48 hours” before showing symptoms.
“This helps explain how rapidly this virus continues to spread across the country, because we have asymptomatic transmitters and we have individuals who are transmitting 48 hours before they become symptomatic,” Dr. Redfield said.
- Advice on masks is changing as coronavirus knowledge evolves
- Dr. John Campbell’s To mask or not to mask: explains the continuum of projected breathing, cough or sneeze releases both droplet and aerosolized virus, thus a mask is very useful for controlling this
- What We Need to Understand About Asymptomatic Carriers if We’re Going to Beat Coronavirus
In recent days, there’s been a new enthusiasm for masks, with many calling for widespread use among the general public. The idea there is that masks could help prevent droplets from traveling far, particularly from an asymptomatic person who doesn’t yet realize they’re infected.
Leung, from the University of Hong Kong, is a fan of this idea. “Wear a mask, preferably universally in public spaces,” he said, when I asked him how to solve the problem of asymptomatic transmission.
- N95, surgical face mask or DIY? Experts say ‘something better than nothing’
“The other use of masks is to stop the spread of the illness by carriers of the virus, referred as ‘source control’, who in the case of coronavirus may well be asymptomatic,” Chughtai said.
“If a high rate of transmission is ongoing in the community, like in the US now, people should use masks, because we know there is a high level of asymptomatic cases. For source control, you can use any mask – even cloth masks are fine.” source
Experts warn, however, that cloth coverings should be properly fitted snugly to the face and they should be washed after use.
- Why that about-face on wearing masks is a problem
We may lack some gold-standard study to support general masking, but if that’s the standard of evidence we’ve been waiting for—well, I have some bad news about social distancing.
We are engaged in a massive, global experiment in how to curb the worst effects of a pandemic. Almost every measure we’re employing to that end is theoretical.
- What’s the Best Material for a Mask?
- The Face Mask Debate Reveals a Scientific Double Standard: No one complained about the lack of evidence for 20-second hand-washing. So why did we treat face masks differently?
- How NOT to Wear a Mask: Wearing a face mask takes some getting used to. To get the most benefit, you need to avoid these common mistakes.
- Coronavirus kills some people and hardly affects others: How is that possible?
This new understanding about the role of “silent spreaders” is why the Centers for Disease Control and Prevention and other health authorities are now suggesting that people wear masks when they leave the house. The recommendation is primarily designed to keep asymptomatic people from unwittingly spreading a disease they may not even know they have.
- Mask-Wearing, Common in Asia, Spreads in the West
- The Social Distancer’s Guide to Urban Etiquette and Ethics
There’s been a lot of mixed messaging on masks…wearing even homemade face coverings on trips outside can have multiple benefits: If worn correctly, covering your mouth and nose can prevent you from contracting the virus, spreading it, and touching your face. Even the CDC has since revised its skepticism, issuing a national recommendation on April 3 for everyone in the U.S. to start wearing them in public…
And here’s another thing. You know all these protocols we’ve been covering about staying six feet apart? Well, some experts say droplets from strong coughs and sneezes can travel 20 feet. So if you just distance and you don’t wear a mask, well, you do the math.
- Germany eyes some normality after bringing coronavirus outbreak ‘under control’
There is no universal requirement to wear protective face masks but instead a strong recommendation to do so.
Face masks in Germany are recommended in public places but not mandatory. Photo by SCMP
- In Japan, dirty face masks spark online backlash against prime minister
- The TRUTH about FACE MASKS (KN95) for CORONAVIRUS (COVID-19): Good info about various types of face masks, what to watch out for, getting product from China, and how we can all encourage domestic manufacturers to produce face masks
- Nose is a point of entry for coronavirus as West reinforces early Chinese research
- ‘We’re dogs without tails’: how face masks affect human interaction – and what to do about it
- Masks protect the wearer, too – and lower our risk for contracting COVID-19
- Mike Pence flouts hospital policy and goes maskless in Mayo Clinic visit
On April 13, Mayo Clinic announced that all patients and visitors would need to wear a face covering or mask to slow the spread of Covid-19, based on advice from the US Centres for Disease Control and Prevention. According to that CDC guidance, wearing masks in public can lower the risks of transmitting the virus, including from people who show no symptoms of the virus.
- Airborne Coronavirus Detected in Wuhan Hospitals
The paper did not state whether people passing through those areas were wearing masks, which would block much of the virus a sick person breathes out.
- ‘We follow the science’: UK government resists public face mask rules in coronavirus battle
- Stylish and made in France, face mask President Macron wore to accessorise his suit raises profile of cloth masks everyone in France will soon be wearing in public
French President Macron wears a stylish face mask with the strips of the French flag. He sets a good example. From SCMP.
Slovakian President Caputova wears a nice raspberry face mask that matches her outfit. SCMP
- The retired inventor of N95 masks is back at work, mostly for free, to fight covid-19
His central finding was that N95 masks can be heated at 158 degrees Fahrenheit for 60 minutes using a dry heat method without diminishing the filtration technology, and his hypothesis was validated by the National Institutes of Health…
He’s spread the word about the optimal material to use for homemade masks. His suggestion: nonwoven fabrics, such as car shop towels.
- N95 Respirator Cleaning and Reuse Methods Proposed by the Inventor of the N95 Mask Material
- Which DIY mask pattern should you use? Even experts can’t pick one to recommend
The basics? Good coverage is important. The mask should reach above the bridge of the nose and below the chin. Fit is important. A mask should be snug. A fabric tie might work better than an elastic band. And if a mask is going to be reused, it must be kept clean. Layers add additional protection, so three-ply is good, as is including a small pocket or pouch, into which an additional filter can be inserted…
When selecting material, a trade-off must be made between filtration efficiency and breathability…
Peter Tsai, the materials scientist who invented the electrostatic charging technology that N95 masks — the highest-quality medical masks on the market — rely on, also believes that homemade masks are an important part of the United States’ battle against the coronavirus. He offered another material for DIY mask makers to consider: nonwoven fabrics.
Nonwoven fabrics, which Tsai did years of research on to improve medical masks, are made of individual fibers or filaments that are bound together mechanically, thermally or chemically. They are not knit or woven together, like most cotton.
Not all nonwoven fabrics are ideal for masks. Wet wipes are made of nonwoven fabric but are too porous, Tsai said. Vacuum bags are also generally made of nonwoven fabric but are not breathable.
Tsai recommended using car shop towels as mask material. The towels, available in rolls and often blue in color, would do a better job of filtering droplets than cloth, he said. The material is “very strong,” he said. “And it can be washed with soap and water and reused.” There are YouTube videos that offer tutorials on using this material.
The towels, he said, could also be used in conjunction with cloth masks, serving as an additional filtering layer.
Big Weed has sewn this style of face mask, DIY Mask making 立体マスクの型紙の書き方 作り方 布口罩製作教程 마스크를 만드는 방법. It has a rectangle across the front, with inner peaks for the nose and chin. It looks interesting. Here is another video (PDF)wear glasse sAvailable in multiple sizes DIY Mask making 複数のサイズで利用可能 立体マスクの型紙の書き方 作り方 布口罩製作教程, from the same person, in Taiwan. The template is here. Same design, different person: [DIY]필터 교체형 마스크 / Filter and Wire Replaceable Mask / DIY ‘หน้ากากผ้า /フィルターポケットマスク. There’s one sewing step that is in a different order.