Tian Chunyan, a chief engineer at a state-owned building company in Beijing, urged the government to introduce a law against such superstitions.

She told the Science and Technology Daily: “Some construction crews have come to treat it as a ‘rule’, as they believe there will be filth if a woman enters a tunnel and that would cause a collapse. This is obviously nonsense that has no scientific basis. It’s discrimination.”

Many Chinese were shocked to learn that such beliefs still exist in a country that is building more tunnels than any other nation across the world.

“Such ‘rules’ that smell rotten are the obstacles to the scientific construction of infrastructure and must be removed completely,” Zhang Li, a commentator, wrote in Beijing Evening News, a state-owned newspaper.