When will the heavily polluted weather in Xi 'an be lifted?

In view of the heavy polluted weather in Xi 'an, the Emergency Plan for Heavy Polluted Weather in Xi 'an (revised draft in 2020) provides corresponding management measures and treatment processes. By setting different warning levels and response levels, the plan manages the period when serious air recovery occurs or will occur in the city. In this case, after the assessment of the relevant departments and the approval of the headquarters, the early warning of a specific level can be announced to be lifted.