site.btaSofia Meets Annual Fine Particle Pollution Standard for Third Consecutive Year

Sofia has met the annual average limit for fine particulate matter (PM10) concentrations for the third consecutive year, city officials announced at a press conference presenting the results of the low-emission zone for vehicles during the 2025/2026 winter season. The results, covering the period from December 1, 2025 to February 28, 2026, were presented by Deputy Mayor for Environment Nikola Nedelkov and Deputy Mayor for Transport and Urban Mobility Viktor Chaushev.

According to Nedelkov, around 4,000 people in Bulgaria die each year due to air pollution. He noted that in 2025 pollution levels fell below the annual limit of 40 micrograms per cubic meter, reflecting the impact of a comprehensive approach that includes transport measures, restrictions on solid-fuel heating, stricter control, and expansion of green spaces.

In nine Sofia districts, the use of solid fuels for household heating has already been banned, with the measure set to cover the entire city by 2029. The municipality has replaced more than 20,000 old firewood or coal stoves so far, cutting an estimated 219 tonnes of fine particle emissions annually, and plans to support another 10,000 households.

The low-emission zone, introduced in central Sofia, is part of these broader efforts and aims to reduce traffic-related pollution during the winter months, when health risks are highest. This zone is off-limits for older and more polluting vehicles.

Data show improved compliance with vehicle restrictions. In the “small ring” in central Sofia, violations dropped by 42% in 2025/2026 compared to the previous season. In the wider “big ring,” violations decreased by 21% between December and February.

Chaushev said the city is also investing in cleaner public transport to provide alternatives to private cars. Plans include the purchase of new trams, 75 trolleybuses and 50 electric buses, as well as track repairs on major boulevards and the expansion of the metro network with three new stations toward the northeastern neighborhood of Levski G.

City officials said the combined measures are delivering tangible improvements in air quality and encouraging residents to shift toward more sustainable transport options.