Evaluation of real-world vehicle emissions in Kampala, Uganda

Vehicle-related air pollution is a major challenge in Kampala, Uganda, where annual average ambient fine particulate matter (PM2.5) pollution exceeds World Health Organization guidelines by at least 8 times. The heavy reliance on private
cars, motorcycles, and informal minibus transport systems presents a challenge for addressing traffic-related air pollution in the city, and comprehensive policies are needed to reduce vehicle emissions.

Currently, Uganda enforces a 15-year age limit on imported light-duty vehicles and no age limit on imported heavy-duty
vehicles. The National Environment (Air Quality Standards) Regulations, 2024 adopted Euro 4 emission limits on all
vehicle imports, both new and used, but the extent to which these standards are currently enforced is uncertain. The same uncertainty surrounds enforcement of the routine vehicle inspection program described in Uganda’s Traffic and Road Safety (Motor Vehicle Inspection) Regulations, 2016. In this context, real-world vehicle emissions data from Kampala are critical to understanding the transport sector’s contribution to air pollution in the city.

In July 2024, The Real Urban Emissions (TRUE) Initiative partnered with the United Nations Environment Programme and local researchers and authorities to employ a plume chasing remote sensing technique in Kampala. Vehicles were followed to measure their real-world emissions and nearly 6,000 measurements of nitrogen oxides (NOX), nitrogen dioxide (NO2), black carbon (BC), and particle number (PN) were collected across multiple vehicle types, including passenger cars, motorcycles, minibuses, large buses, light commercial vehicles (LCVs), and heavy commercial vehicles (HCVs). 

This report examines the distribution, characteristics, and emissions of vehicles measured in Kampala and then identifies ways that policy can help reduce vehicle-related pollution. The findings of the TRUE Kampala real-world vehicle emissions analysis highlight that an age limit alone cannot guarantee lower-emitting vehicles in Uganda.