Qinhuangdao, China’s largest coal shipping port, has adopted a regulation to prevent air emissions from ships, local authorities said. The regulation, which has taken effect on December 1, stipulates that ships that emit “visible black smoke” for three minutes and above will be punished. Priority will be given to the ships powered by fuel oil with sulphur content below 0.1% m/m in entry, load and unload, and departure of the port. The number of merchant ships in and out of Qinhuangdao has reached 14,000 so far in 2019.