Proportion of periods of good air quality increased at all measuring points
In October–December, the proportion of periods of good air quality increased at the Mannerheimintie, Leppävaara and Tikkurila measuring points in comparison to the corresponding period in the previous year.
In October–December, the average proportions of periods of good air quality totalled 82.5 per cent in Tikkurila, 79.4 per cent in Leppävaara and 73.1 per cent on Mannerheimintie. The air quality was mainly satisfactory during other periods.
In Leppävaara and Tikkurila, the air quality has been mostly good since 2018. In Leppävaara and Tikkurila, the air quality has been good for most of the time since 2015. Street dust decreases the air quality especially in the spring.