NEW DELHI, Jan. 10 -- Union environment minister Harsh Vardhan will launch the much-awaited National Clean Air Programme (NCAP) on Thursday to reduce the concentration of PM2.5 (fine, respirable pollution particles) and PM10 (coarse pollution particles) by 20% to 30% by 2024 over the 2017 annual average levels.

According to senior ministry officials, the plan will be collaborative and participatory in nature, which means it will not be legally binding on states."We are considering a collaborative and participatory approach involving relevant central ministries, state governments, local bodies and other stakeholders with focus on all sources of pollution," said a senior environment ministry.

Besides strategies to reduce air pollution conce...