A man wears a gas mask as he holds a bouquet of flowers, following the outbreak of the novel coronavirus on Valentine’s Day in Hong Kong, China on February 14, 2020. (Photo by Tyrone Siu/Reuters)

Gas-masked men of the British Machine Gun Corps with a Vickers machine gun during the first battle of the Somme, 1916. (Photo by General Photographic Agency/Getty Images)

Men wearing masks and dressed as military members take part in a festival honouring San Silvestre, in the town of Catarina, Nicaragua January 1, 2016. The placard reads, “I'm not afraid, young people off the streets, Ortega you sell our country”, in reference Nicaragua's President Daniel Ortega. (Photo by Oswaldo Rivas/Reuters)

Ballet dancer and performer Ashlee Montague of New York wears a gas mask while she dances in Times Square as the coronavirus disease (COVID-19) outbreak continued in Manhattan, New York City, U.S., March 18, 2020. (Photo by Andrew Kelly/Reuters)

A masked protester talks to a soldier during clashes after the funeral of Brig. Gen. Wissam al-Hassan October 21, 2012. Lebanese soldiers fired guns and tear gas to push back hundreds of protesters who broke through a police cordon and tried to storm the government headquarters in Beirut. (Photo by Hussein Malla/Associated Press)

A government awareness poster for wearing surgical masks is seen reflected and upside-down in the Dambovita river in Bucharest, Romania, 19 November 2020. The poster, depicting a man wearing a surgical mask, reads: “I WEAR A MASK BECAUSE I KNOW THAT ONLY TOGETHER WE WILL SUCCEED!”. As the number of COVID-19 infections increased, authorities decided that wearing a protective mask should become mandatory at all times in all public places. (Photo by Robert Ghement/EPA/EFE)

Protesters wear gas masks in the front of the Romanian Environment Ministry in Bucharest March 4, 2019, to demand better air. Dozens of people holding placards reading “Our children don't breath air anymore” gather in the front of the Environment Ministry to ask for better breathable air in Bucharest. (Photo by Daniel Mihailescu/AFP Photo)

A doll in a children's gas mask is seen amongst beds at a kindergarten in the abandoned city of Pripyat near the Chernobyl nuclear power plant in Ukraine on March 28, 2016. Deadly radiation still spews from Chernobyl 30 years after the worst nuclear meltdown in history, as a newly built giant arch is pulled into place to cover the stricken reactor for the next century. (Photo by Gleb Garanich/Reuters)