China's top steelmaking province of Hebei will order its steel mills to comply with new emissions standards, the strictest ever, from the beginning of 2019 as part of its campaign against air pollution, according to new industry guidelines on the provincial government's website on Friday October 12.

New  steel mills will be subject to "ultra-low" emissions restrictions from January 1, 2019, while existing firms will have to meet new standards by October 1, 2020.

Particulate matter emissions will need to be kept under 10 micrograms per cubic metre, sulphur dioxide emissions below 35 micrograms and nitrogen oxides less than 50 micrograms. The new standards are stricter than state limits, which stand at 40, 180 and 300 micrograms for the three emissions, respectively.