Fine dust varies by 60% across Seoul, says KT

Within Seoul, daily fine dust levels can vary by as much as 60 percent, according to data from KT’s air quality monitoring project.

The mobile carrier on Thursday unveiled the results of its Air Map Korea project, which began in September last year. The project monitored the air quality of Seoul as well as that of six other major metropolitan cities in Korea.

KT installed dust monitoring device in 1,500 selected areas, taking advantage of its existing infrastructure.

The devices are connected to the internet and update air quality data every minute to KT’s online platform. They tracked fine dust, ultrafine dust, temperature and humidity to determine air quality. Ultrafine dust refers to particulate matter with a diameter of 2.5 micrometers or less.

Based on its research, KT found that fine dust levels vary greatly even within a single city, depending on the time of the day, rainfall and building height. There was a big difference in air quality between outdoors and indoors, as well.

In Seoul, KT installed 512 monitoring devices. Gwangjin District, eastern Seoul, the most polluted among the 25 districts of the city, had 44 micrograms more fine dust per cubic meter compared to the least polluted area, Yangcheon District, western Seoul, on April 6. That day was one of the dustiest days this spring in Korea, and professional baseball games were canceled due to the pollution levels.

Buildings ventilated with air purifiers, such as classrooms at schools, had 60 percent better air quality compared to outdoors. Inside buildings, air quality tended to improve the higher the floor was. Rain helped remove fine dust from the air. When more than 10 millimeters (0.40 inches) of rain fell, it cut fine dust levels by roughly 70 percent, according to KT.

KT plans to offer its data to the government first, so the country can have a more detailed air quality data set to prevent further pollution.

BY KIM JEE-HEE [kim.jeehee@joongang.co.kr]