Everyday mask

from Wikipedia, the free encyclopedia
Homemade everyday mask with straps
Self-sewn everyday masks with elastic bands, adapted to the shape of the face
Hand-sewn everyday mask made of two layers of cotton fabric with straps
Hand-sewn makeshift mouth and nose mask made of cotton with folds ironed in before sewing, can be disinfected by ironing
A double-layered cloth can satisfy the mask requirement, but has insufficient filtering effect.

An everyday mask is a tailored piece of cloth that is worn over the nose , mouth and chin . It usually consists of cotton fabric that is sewn in folds or tailored to the shape of the face, and is fixed with elastic bands on the ears or with straps on the back of the head. It is possible to work a metal wire into the fabric above the nose. The mask should be as close as possible to the face. Further names are community mask , mouth and nose covering (MNB), makeshift mouth and nose mask and makeshift mask . Self-made masks are also known as DIY masks ( do-it-yourself masks).

Cloth face masks were regularly used by health care professionals from the late 19th century through the mid 20th century. In the 1960s, their use in industrialized countries declined in favor of modern medical masks for reasons of hygiene. However , they continued to be used in developing countries . During the COVID-19 pandemic , mouth and nose coverings were made mandatory in numerous countries.

Behelfsmasken may not commercial "as a medical device or objects personal protective equipment placed on the market and not with corresponding benefits or protective effects awarded are" but will be used exclusively in the private sphere, as they - unlike medical full-face protection (MNS) and respirators as FFP2 and FFP3 masks - not subject to regulation. There are therefore few reliable, generalizable statements about their effectiveness as protection against the transmission of infections or fine dust .

Manufacturing

The sewing a Behelfsmaske

Various types of cloth masks are available on the market. In the case of masks made in private households, the variety of manufacturing methods and products is even greater.

Manufacturer

During the COVID-19 pandemic , there was suddenly a great need for mouth and nose covers. Since then, corresponding masks have been made by numerous professional tailors and seamstresses who otherwise work, for example, as tailors for alterations or in the costume departments of theaters. Larger companies also got into production, in Germany for example the companies Trigema , Mey , Breckle and others. The first fashion house for everyday masks has existed in Germany since April 2020, and a start-up entrepreneur in the Lausitz region is evaluating everyday masks as the company's new item of clothing.

In addition, makeshift masks are made in countless households as well as by committed helpers and groups.

Homemade masks

Instructions for sewing DIY masks (“ do-it-yourself masks”) have been published by various institutions, for example by the city of Essen and by celebrities, including the fashion designer Guido Maria Kretschmer .

In addition, various ways of producing masks without sewing have been made known in the print media and on the Internet, including by the American health authority CDC . According to this, suitable mouth and nose covers can be produced from common household materials with the simplest means and without tools.

materials

Mostly cotton fabrics are used. Homemade masks can e.g. B. from T-shirts , bandanas , handkerchiefs , scarves , tube scarves or towels . Hong Kong scientists invented a do-it-yourself mask made from two types of tissue paper in February 2020 .

According to a study by the Max Planck Institute for Chemistry , many common household materials are suitable for making masks that can reduce the risk of infection with the coronavirus : in addition to various cotton fabrics, for example, paper towels from kitchen rolls or fleece from vacuum cleaner bags . A major vacuum cleaner bag manufacturer pointed out that their vacuum cleaner bags were not designed to be used as a mask.

Makeshift masks differ from the legally regulated medical face and nose protective masks (standard: EN 14683: 2019) and respiratory masks, which are made from non-woven fabric that is shaped in a meltblown process.

use

Manual of the American health authority CDC for use and production of everyday masks during COVID-19 pandemic 2019-2020

Reusable fabric face masks have long been used in Asia and developing countries .

In health care they are used by infectious patients as "source control". This reduces the transmission of pathogens that are in breath droplets . Healthcare workers are only allowed to wear them when medical face mask and face masks are not available. The use of makeshift full face masks is generally recommended only as a last resort when more effective masks are not available. They are mainly worn in public.

In the Swiss Influenza Pandemic Plan 2018 , only the use of hygiene masks (surgical masks, mouth and nose protection MNS) and respiratory masks (FFP1, FFP2, FFP3) is provided, but not the use of everyday masks.

Processing for reuse

According to the Federal Institute for Drugs and Medical Devices, face masks made of fabric can be washed “ideally at 95 ° C, but at least at 60 ° C” and then reused after drying.

effectiveness

Filter effect on different materials for self-made masks
Effect of sneezing without a face mask
With the help of streak photography , the effect of various barriers on the breathing flow when sneezing can be visualized

Like medical mouth and nose protection, but unlike respiratory masks, everyday masks are not airtight at the edge.

As of 2015, there was no randomized controlled study or recommendation on the use of reusable fabric masks. Most of the research took place in the early 20th century, before disposable medical masks became common.

Until 2006, fabric masks were not approved for use as medical masks by the U.S. Food and Drug Administration .

No self-protection effect has been proven for fabric masks, but they can reduce the speed of the respiratory flow or saliva / mucus droplet ejection and thus reduce the transmission of viruses and bacteria from an infected person to previously uninfected people ( droplet infection ) as well as "the awareness of ' social distancing 'as well as health-related, mindful treatment of oneself and others "(according to the assessment of the Federal Institute for Drugs and Medical Devices ; many other studies and institutes come to comparable conclusions). At the same time, it is regularly pointed out that wearers of self-made “community masks” cannot rely solely on the fact that they protect themselves or others from the transmission of viruses, in particular SARS-CoV-2 viruses, because the quality of this is not good standardized masks differ greatly from one another. The illustration on the right shows different materials used for everyday masks in terms of their filtration efficiency.

A reduction in droplet release has also been demonstrated for other pathogens transmitted by droplet infection.

General hygiene considerations

As part of the preventive measures, especially before COVID-19, it became common knowledge that a minimum distance of one and a half meters must be maintained in order not to be exposed to the virus-containing aerosol of other people. But even if there is no risk of infection, you are exposed to aerosols, i.e. the saliva ejected from other people. If you want to protect yourself and others from this saliva expulsion, a mouth and nose mask is generally recommended in crowds of people or in close proximity to strangers.

history

During the 1918 Spanish Flu , a Seattle tram conductor turned a person away from boarding without wearing a mask

The first proven use of cloth face masks was that of the French surgeon Paul Berger during an operation in Paris in 1897. Masks came into use in the early 20th century to protect against infection. A design by the Chinese doctor Wu Lien-teh , who worked at the Chinese imperial court during a plague epidemic in the fall of 1910, was the first to be empirically tested. He inspired masks that were used during the 1918 Spanish flu . The first study of masks worn by health care workers was in 1918.

The Spanish flu (1918–1920) claimed 390,000 lives in Japan . At that time the Japanese government put up posters with the message: “Beware of germs! You risk your life if you don't wear a mask! ”Since then, the use of face masks in Japan has increased steadily. Today masks are part of the street scene in Japan; however, these are cellulose masks for single use.

When Sweden was badly hit by the Spanish flu in the middle of 1918, the effectiveness of face masks was recognized within a few weeks:

"[A] ll these people, who have to be in constant contact with sick people [...], were equipped with face masks that, similar to war gas masks, covered the whole face up to the chin, leaving the eyes free. [...] The reason for the introduction of these masks was the fact, which had been established by our most important clinicians and hygienists, that the transmission of pathogens is more indirect-contagious, i.e. through the air as a medium, than from person to person (direct- contagious) takes place, which means that the air in the sickroom, which is particularly saturated with germs, also gives a very special chance of infection. "

- Report by a Swedish doctor, quoted in the foreign newspaper , August 5, 1918

The wearing of masks was also recommended in Switzerland in 1918:

“Professor Galli-Valerio in Lausanne recommends that all people who are afraid of contracting the Spanish flu wear a mask, as the flu is spread through saliva that penetrates the nose, mouth, etc. The sanitary city service of Lausanne has produced two models of protective masks, which were tested in the hospital in Lausanne. "

- Note in the Prager Tagblatt , August 14, 1918

By 1919 at the latest it was known that the masks offer a certain protection despite all the problems in use:

“The masks have been recommended by many as a prophylactic agent. A number of models exist. The subsequent masks are very reluctantly worn by the nurses and the maintenance staff, as they get slightly damp when working and then hardly let any air through. Lenz states that you can get used to the mask. It seems to work with doctors, but not with the somewhat harder working staff. Infections have also occurred despite strict wearing of the masks, but only minor illnesses. The masks seem to provide a certain protection. "

- Wiener Klinische Rundschau, August 5, 1918

In the 1940s, cheesecloth masks were used in the United States to protect nurses from tuberculosis .

Fabric face masks were largely supplanted by modern medical disposable masks made of nonwoven fabric in the 1960s in the industrialized world . However, they were used in Asia during the SARS pandemic of 2002/2003 and in West Africa during the Ebola fever epidemic of 2014-2016 .

COVID-19 pandemic 2020

Mouth and nose coverings from an epidemiological point of view

With COVID-19 , the base reproduction number is around 3, which means that without measures, each infected person would infect around three other people on average and the disease would spread rapidly and exponentially . In addition, the transmission of the disease is greatly facilitated by the fact that the infectiousness of COVID-19 already exists in the incubation period , even before symptoms appear - or without symptoms ever developing. This results in the need for measures such as social distancing , hygiene rules and the wearing of mouth and nose covers in public.

The importance of mouth and nose covers (masks) arises from the fact that COVID-19 is mainly transmitted by droplet infection . Droplets when sneezing , coughing and also (directed when sneezing and coughing briefly in large quantities while speaking also in large quantities and, where appropriate, over time, to the other party) while speaking ejected. In all of these cases, masks do not offer complete, but relatively effective protection against transmission (reduction of the risk of infection), as droplets are caught by the tissue. Even when pronouncing individual words, hundreds of droplets of the order of 20–500 µm can emerge from the mouth. They almost completely hang in a suitable cloth in front of the mouth. Due to the effect of catching droplets for the most part before they hit a person nearby or can spread around the room, everyday masks are primarily used for external protection, i.e. the protection of other people (see also above on effectiveness ).

According to the Robert Koch Institute , wearing mouth and nose covers in public is to be assessed as an “additional component” with which the speed of spread of COVID-19 can be reduced. It is absolutely necessary to continue to observe the other measures: at least 1.5 meters away from other people, coughing and sneezing rules, good hand hygiene and isolation from sick people and suspected cases. Wearing mouth and nose covers is particularly useful if several people stay in closed rooms for a long time (e.g. at the workplace) or if the minimum distance cannot be maintained (e.g. in shops and on public transport) .

Recommendations for wearing everyday masks

MPs in the parliament of East Timor with masks and side protection (April 2020)

Wearing masks in public was initially recommended in many places. In March 2020, doctors from Hong Kong recommended that this practice, as it was previously common in Asian countries, also be introduced in other countries. In March 2020, the virologist Alexander Kekulé also suggested that the widespread wearing of protective masks could prevent a worse outbreak there, and therefore recommended that the population (and especially employees with a lot of personal contact) constantly wear mouth and nose protection in public to wear, even if they are just simple masks. Shortly beforehand, the German Association of General Practitioners had also made a recommendation for the population to wear mouth and nose protection and suggested that general practitioners be involved in the distribution.

In March 2020, the Washington Post published an article by data scientist Jeremy Howard advocating that everyone in public should wear a self-made protective mask to contain the spread of the virus, in addition to other measures. The author bases his plea on the evaluation of the previous specialist literature on the effect of different masks.

In addition, in March 2020, the U.S. Department of Health and Safety at Centers for Disease Control and Prevention (CDC) recommended that if respirators and medical mouth and nose masks are not available, everyday masks can be used by healthcare workers as a last resort, that have not been tested and approved by the National Institute for Occupational Safety and Health . However, it should be used with great caution and other hygiene measures should not be neglected. In April 2020, the CDC recommended that all citizens cover their mouth and nose in public with cloth if spatial distancing measures were difficult to implement, such as in shops or pharmacies. The purpose of the mouth and nose covering is to protect others from infection. It should consist of several layers of fabric and lie close to the face, but not hinder breathing.

In Germany, the Federal Institute for Drugs and Medical Devices (BfArM) has also issued recommendations for the use and preparation of makeshift masks. Suitable masks could "make a contribution to reducing the further spread of SARS-CoV-2". However, wearers of the described 'community masks' could "not rely on them protecting themselves or others from the transmission of SARS-CoV-2, since no corresponding protective effect has been proven for these masks."

On April 15, 2020, the federal and state governments made an “urgent recommendation” to wear “everyday masks” in retail and local public transport .

Mask requirement

The Czech Republic made it compulsory to wear “face masks” as part of the state of emergency imposed on March 12, 2020 in public spaces. In Austria, a similar regulation was passed for supermarkets at the end of March.

On April 3, 2020, the Leopoldina called for a mask requirement in Germany. Jena was the first city in Germany to introduce a mask requirement at the beginning of April (in three stages on April 1, 6 and 10, 2020). On April 14, 2020, the Robert Koch Institute (RKI) issued a recommendation for the situation-dependent wearing of a mouth and nose cover (MNB) , which the federal and state governments followed on the same day. On April 17, 2020, Saxony was the first federal state to issue a mask requirement in shops and in local transport. The other federal states followed shortly thereafter; the individual state governments each made their own decisions, which will be implemented from April 27, 2020. The virologist Christian Drosten expressed his conviction in June 2020 that the mask requirement in Germany had made a major contribution to keeping the number of new infections relatively low and recommended that this measure be maintained.

In most countries around the world, a nationwide mask requirement was introduced, mostly in April or May 2020. On May 26, 2020 there were 116 countries in which masks must be worn nationwide, either in public or at least in certain environments (for Example in public transport and / or in shops). In the United States , Mexico , Brazil and 15 other countries, a mask was mandatory in parts of the respective country at that time. In the People's Republic of China , India , Japan , Malaysia and South Korea , no mask requirement was introduced because the wearing of mouth and nose covers was already practiced in these countries. In 18 countries, including the United Kingdom and Switzerland , the wearing of masks was not mandatory but recommended. As far as is known, on May 26, 2020 there was only a few countries where there was neither an obligation nor an official recommendation to wear masks: Denmark , Norway , Sweden , Finland , Australia , New Zealand and Turkmenistan . For around 30 other countries without a mask requirement, clear information on recommendations for wearing masks was not available.

The Switzerland and Ireland led a mask requirement in the 13 July 2020 public transport one. In Ireland, violations can be fined up to € 2,500 and imprisoned for six months.

France actually didn't want to introduce a mask requirement in closed public spaces until August. After strong criticism, it is now valid from July 20th. New Corona hotspots and a high-risk area in the Mayenne department have alerted decision-makers and many citizens.

Comparison of mask types

Effectiveness of everyday masks compared to other types of masks

Everyday masks offer the wearer of the mask little self-protection, as do cloths or scarves with which the mouth and nose area is covered. Everyday masks are therefore not regarded as protective masks, but as a makeshift replacement for protective masks.

Still, simple mouth and nose covers can go a long way towards containing the pandemic. Their usefulness results from the principle of mutual protection from others: Under the conditions of a general mask obligation, mask wearers protect each other in public. Since professional respiratory masks can intercept droplets and aerosols much more effectively, the external protection provided by everyday masks is only rated as low to moderate.

Medical hygiene masks (surgical masks, medical mouth and nose protection) are somewhat more effective than everyday masks for self-protection and external protection, but much less effective than professional breathing masks.

FFP2 and FFP3 masks offer significantly increased self-protection compared to everyday masks. These professional respirators are worn by medical personnel who care for, treat and care for people suspected or ill with COVID-19. But they also offer people who are at a higher risk of severe COVID-19 disease more self-protection. FFP masks are available with and without an exhalation valve. Valved masks only filter the air that is inhaled. When you exhale (including any viruses that may be present), it gets into the environment unfiltered. These masks do not offer any third-party protection and are therefore unsuitable for compliance with the mask requirement, which is primarily based on mutual protection, in public.

A comparative overview of various masks that are used in the COVID-19 pandemic can be found under protective mask .

Face shields as an alternative

Face shields recognize the following federal states as mouth and nose covering: Hamburg, Hesse, Rhineland-Palatinate and Schleswig-Holstein. These are also a barrier to prevent droplet infection and, in contrast to masks, also protect the eye as a gateway. On the other hand, there is the disadvantage that the spread of virus-containing aerosols is not reduced by face shields.

See also

Web links

Commons : Cloth Masks  - collection of images, videos and audio files

Individual evidence

  1. ↑ The term community mask refers to the wearing of the masks in public (English community ). See statement of the ECDC , April 8, 2020: “Using face masks in the community”, “the use of masks in the community” etc.
  2. ↑ a b c d e f g Information from the BfArM on the use of self-made masks (so-called "community masks"), medical mouth and nose protection (MNS) and filtering half masks (FFP2 and FFP3) in connection with the coronavirus (SARS -CoV-2 / Covid-19) bfarm.de, as of March 31, 2020.
  3. ↑ Examples: Corona crisis: Tailors want to help and sew face masks themselves fuldaerzeitung.de, March 28, 2020; Mouth and nose masks Staatstheater-mainz.com; Costume tailoring sews masks: Theaters help in a crisis welt.de, March 31, 2020.
  4. ↑ More and more companies are switching to: face masks instead of underwear, shirts and mattresses suedkurier.de, March 27, 2020.
  5. ↑ Examples: Helpers sew masks in schools in Saarbrücken and Völklingen saarbruecker-zeitung.de, April 24, 2020; Volunteer seamstresses sew masks for the community stuttgarter-zeitung.de, May 1, 2020.
  6. ↑ Coronavirus: Sewing and care instructions for makeshift mouth and nose protection essen.de, accessed on April 11, 2020.
  7. ↑ Guido Maria Kretschmer helps with mask sewing wn.de, April 7, 2020.
  8. ↑ Example: Quick and easy! How to make a mask - in under 1 minute heidelberg24.de, May 9, 2020.
  9. ↑ a b c d e Use Cloth Face Coverings to Help Slow Spread. In: cdc.gov. Accessed April 13, 2020 (English).
  10. ↑ Reusability of Facemasks During influenza Pandemic: Facing the Flu . The National Academies Press, Washington DC 2006, ISBN 978-0-309-10182-0 , pp. 62 , doi : 10.17226 / 11637 (English).
  11. ↑ How to make your own mask: Hong Kong scientists reveal temporary solution for those unable to get protective gear because of panic buying and price-gouging South China Morning Post , February 14, 2020.
  12. ↑ Make your own protective mask without sewing: This is what the expert recommends praxistipps.chip.de, April 28, 2020.
  13. ↑ Fabrics, paper towels or vacuum cleaner bags against Corona mpg.de, April 10, 2020.
  14. ↑ Statement on the use of Swirl® filter products for the manufacture of breathing masks swirl.de, April 24, 2020
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  21. ↑ Which everyday mask filters best?
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  23. ^ Mark Wilson: The N95 mask: The untold origin story. In: fastcompany.com. March 24, 2020, accessed April 13, 2020 .
  24. ↑ Theresa Locker: A Brief Cultural History of Mouthguards in Japanese Streets Vice.com, January 16, 2015
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  27. ↑ The masked Swiss . In: Prager Tagblatt . August 14, 1918, p. 2 ( ANNO - AustriaN Newspapers Online [accessed on May 25, 2020]).
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  29. ↑ Esta H. McNett, RN: The Face Mask in Tuberculosis: How the cheese-cloth face mask has been developed as a protective agent in tuberculosis . In: American Journal of Nursing . 1st edition. tape 49 , January 1949, p. 32-36 (English, journals.lww.com ).
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  32. ↑ a b Visualizing Speech-Generated Oral Fluid Droplets with Laser Light Scattering nejm.org, April 15, 2020 (see also the included video).
  33. ↑ Chi Chiu Leung: Mass masking in the COVID-19 epidemic: people need guidance. The Lancet , March 3, 2020, doi: 10.1016 / S0140-6736 (20) 30520-1
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  35. ↑ prosieben.de
  36. ^ Deutscher Hausärzteverband, Landesverband Niedersachsen: Sewing instructions for makeshift mouth and nose protection. Accessed July 30, 2020 .
  37. ↑ Simple DIY masks could help flatten the curve. We should all wear them in public. www.washingtonpost.com, March 28, 2020.
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  48. ↑ Second ad hoc statement: Coronavirus pandemic - Health-related measures (PDF) German Academy of Natural Scientists Leopoldina , April 3, 2020
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  51. ↑ Telephone conference between the Chancellor and the heads of government of the federal states on April 15, 2020. Press and Information Office of the Federal Government (BPA), press release 124 of April 15, 2020.
  52. ↑ Regulations of the federal states. Where is the mask compulsory? tagesschau.de Status: April 21, 2020; accessed on April 28, 2020.
  53. ↑ Mask requirement a great success n-tv.de, June 12, 2020.
  54. ^ What US States Require Masks In Public? masks4all.co, accessed on May 26, 2020. The list is updated daily.
  55. ^ What Countries Require Masks in Public or Recommend Masks? masks4all.co, accessed on May 26, 2020. The list is updated daily.
  56. ↑ On empty run
  57. ↑ www.gov.ie Guidance on safe use of face coverings
  58. ↑ https://www.faz.net/aktuell/politik/ausland/corona-in-frankreich-maskenpflicht-kommen-frueher-16863542.html
  59. ↑ Overview of different mask types
  60. ↑ Recommendations of the BfArM
  61. ↑ 2019-nCoV transmission through the ocular surface must not be ignored .
  62. ↑ Neeltjevan Doremalen, Dylan H.Morris, Myndi G.Holbrook et al .: Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1 . The New England Journal of Medicine, April 2020.
  63. ^ Nancy HL Leung, Daniel KW Chu et al: Respiratory virus shedding in exhaled breath and efficacy of face masks
  64. ↑ Surgical masks also protect wearers effectively
  65. ↑ doz-verlag.de
  66. ↑ "This implies that simple and easy-to-use barriers to respiratory droplets, along with hand hygiene and avoidance of touching the face, could help prevent community transmission when physical distancing and stay-at-home measures are relaxed or no longer possible. The 2 major options for such barriers are face masks and face shields. " Doi: 10.1001 / jama.2020.7477
  67. ↑ Visualizing Speech-Generated Oral Fluid Droplets with Laser Light Scattering .