A woman wearing a mask reacts at her garden which locates next to chimneys of coal-fired power plant in Shijiazhuang, Hebei province, China, January 28, 2015. Beijing introduced tougher regulations this year to combat pollution, keen to overhaul China's unwanted image of smog-choked cities, fouled waterways and heavy-metal tainted soil. (Photo by Kim Kyung-Hoon/Reuters)

A member of the public wears a pandemic face mask ahead of the prime minister announcing the government's Covid-19 winter strategy on September 13, 2021 in Manchester, England. Tomorrow, British Prime Minister Boris Johnson will set out his plan to manage Covid-19 through the winter, including what actions would need to be taken if the NHS hospital system were at risk of being overwhelmed. (Photo by Christopher Furlong/Getty Images)

A masked reveller poses near Saint Mark's Square during the Venetian Carnival in Venice January 31, 2015. (Photo by Stefano Rellandini/Reuters)

A New York window cleaner strapped to the side of The RCA Building in the Rockefeller Center, with St Patrick's Cathedral below him to the left. (Photo by William Lovelace/Express/Getty Images). 2nd May 1961

A Scots soldier has won a top award for his photos vividly depicting Army life in Afghanistan. Corporal Jamie Peters took the overall first prize for his portfolio in the annual Army Photographic Competition. Photo: Jamie's overall winning image entitled “Celtic Warrior” and shows Private Ross Cunningham from 1 Scots cleaning his personal weapon. (Photo by Jamie Peters/PA Wire)

An Egyptian university student drives a hybrid racing car he built with his team to compete at the Global Hybrid-Electric Challenge in Cairo, Egypt September 2, 2016. (Photo by Mohamed Abd El Ghany/Reuters)

A detail of the Sagrada Familia Basilica, designed by architect Antoni Gaudi, in Barcelona, Spain, Wednesday, October 21, 2015. Barcelona's breathtaking La Sagrada Familia Basilica has begun its final phase of raising six immense towers. Presenting the project Thursday, chief architect Jordi Fauli said the central "Tower of Jesus Christ," the tallest of the six, will rise 172.5 meters (566 feet) high, making it "the tallest religious building in Europe". (Photo by Manu Fernandez/AP Photo)