A short history of mask wearing, from the operating room to 2020

Masks feel like a recent invention, but their story runs back more than a century. This sheet follows five moments, from gauze in an operating theatre to cloth coverings in the street, and ties each to a source that was opened for the purpose. It is a short history, and it leaves out much that other historians would include, because a claim stays out unless a source on hand supports it.

Gauze in the operating room, 1897

A history article in Medical History (April 2022) places the introduction of the medical mask in the late nineteenth century, at the meeting point of surgery and bacteriology. In 1897 the surgeon Johannes Mikulicz at the University of Breslau, now Wroclaw in Poland, used a piece of gauze in front of his nose and mouth as a barrier to keep microorganisms from moving from surgeon to patient. He drew on the bacteriological experiments of his colleague Carl Flügge.

The authors add a useful caution: Mikulicz "did not invent the medical mask, but he gave a new meaning to an old sanitary practice." The mask, in other words, arrived as a germ-control tool for protecting patients from the person wearing it.

Pneumonic plague in Manchuria, 1910 to 1911

A BiblioAsia article by Kevin Y.L. Tan (7 July 2020) describes the Penang-born physician Wu Lien-teh, who arrived in Harbin on Christmas Eve 1910 to deal with the pneumonic plague outbreak. It says he recommended face masks so people could protect themselves and others, and that the mask he used and recommended was a simple cotton and gauze one.

A biographical note in Protein and Cell (29 January 2016) says the epidemic began in the fall of 1910 and claimed over 60,000 lives within four months. Wu concluded it was pneumonic plague, spread by breath or sputum, which went against the common view that plague passed only through rats or fleas. It also records that a doctor who doubted him died after refusing to wear gauze and a mask. The International Plague Conference was held in Mukden from 3 to 28 April 1911, with Wu as president.

Influenza and the 1918 pandemic

The CDC Museum's digital exhibit on influenza records that on 18 October 1918 San Francisco's Health Officer, Dr William Hassler, ordered anyone who worked with the public to wear a mask at work. On 21 October 1918 he urged citizens to wear masks when out of their homes. The exhibit is the only source opened for 1918 here, so the sheet says no more about how widely masks were used or how people responded.

Certified respirators, 1995

A NIOSH summary of the 42 CFR Part 84 final rule says it was made public on 2 June 1995 and scheduled for publication in the Federal Register on 8 June 1995, taking effect on 10 July 1995. The rule replaced earlier regulations with new certification rules and set three filter classes (N, R and P), each at 95%, 99% and 99.97% efficiency. N95 is the class with a 95% minimum efficiency tested against a sodium chloride aerosol. For how these labels sit beside European ones, see the standards sheet.

Cloth masks go mainstream, 2020

On 3 April 2020, the CDC recommended cloth face coverings in public settings where social distancing was hard to maintain, such as grocery stores and pharmacies. It cited new evidence that people without symptoms, or before symptoms, can pass on the virus, and said the coverings were not surgical masks or N95 respirators, which were to be reserved for health-care workers. The sheet on making a cloth mask covers what that route can and cannot offer.

The arc is steady. Masks began as protection for patients from their surgeons, became a tool of epidemic control, and then got testing standards. Modern evidence is more mixed, as the evidence sheet sets out.

The short version

The documented story runs from Mikulicz's gauze in 1897, through Wu Lien-teh's work in the 1910 to 1911 plague and San Francisco's 1918 orders, to NIOSH's 1995 certification classes and the 2020 cloth-covering advice. Each date above rests on a source the editors opened, and popular accounts that go beyond these sources have been left out.