• Under the seasonal PM management, the city’s PM2.5 level declined by 37% while the number of days with ‘good’ PM levels quadrupled.
• The city government will focus on 16 measures across four areas, including transportation and heating, with a target PM2.5 reduction of 141 tons (tentative).
• The number of cars violating the ban on emission grade 5 vehicles declined by 51%, while the number of Seoul eco-friendly construction sites increased.

The Seoul Metropolitan Government (SMG) announced the result of the ‘5th seasonal particulate matter (PM) management’ (“seasonal management”), which lasted from last December to the end of March this year. According to the city government, Seoul’s fine particulate matter (or PM2.5) level has reached the lowest level since the first seasonal management launched in 2019.

* The seasonal PM management is an intensive management effort aimed at lowering PM frequency and levels by implementing stricter preventive measures between December and March, a season with frequent spikes in PM levels. The first seasonal management took place between Dec. 2019 and Mar 2020, followed by the second (Dec. 2020-Mar. 2021), the third (Dec. 2021-Mar. 2022), and the fourth (Dec. 2022-Mar. 2023).

Over the last four months, Seoul took 16 intensive measures across four areas (including transportation, heating, and business site) to reduce winter PM levels. The SMG estimates that the measures reduced PM2.5 by 141 tons and nitrogen oxides by 2,873 tons.

These efforts have resulted in an average PM2.5 concentration of (22 ㎍/㎥) during the seasonal management, the lowest since its implementation. The average PM2.5 concentrations declined by 37% (from 35 to 22 ㎍/㎥) and the number of days with ‘good’ air quality (15 ㎍/㎥ or lower) quadrupled (from 11 to 42 days), compared to the same period before its introduction (Dec. 2018-Mar. 2019).

As for its major achievements, the number of violations of the ban on emission gas grade five vehicles dropped by 51% relative to the fourth management period. The number of eco-friendly construction sites, for which the city government signs agreements with constructors to induce voluntary reduction of fugitive dust) increased from 101 to 150.

The city will conduct an in-depth analysis of the impact of the 5th seasonal management to develop even more enhanced measures for the 6th seasonal management scheduled for this December.