This paper reviews emission factors from light-duty vehicles, focusing on those that followed the recently introduced Global Technical Regulation (GTR 24) methodology on brakes. The study aims to provide up-to-date PM2.5, PM10, and particle number (PN) emission factors for light-duty vehicles and the reduction potential of pads, discs, and regenerative braking. Key findings include: - The airborne and/or PM10 fraction to total wear is approximately 40-45% on average. - Non-asbestos organic (NAO) pads reduce emissions by an average of 62% for PM10, 55% for PM2.5, and 64% for PN compared to ECE pads. - Carbon-ceramic (CC) and hard metal coated (HMC) discs reduce PM10 by 81% and 57%, and PM2.5 by 74% and 60%, respectively. - Brake particle filters have an average PM efficiency of 50% for passive systems and 75% for active systems. - Electrified vehicles are expected to have lower brake emissions due to regenerative braking, but their mass increases by 15-25%. The emission factors are compared with roadside measurements and emission inventories, showing good agreement. The study concludes that the findings can be used to estimate the contribution of brakes to air pollution in emission inventories.This paper reviews emission factors from light-duty vehicles, focusing on those that followed the recently introduced Global Technical Regulation (GTR 24) methodology on brakes. The study aims to provide up-to-date PM2.5, PM10, and particle number (PN) emission factors for light-duty vehicles and the reduction potential of pads, discs, and regenerative braking. Key findings include: - The airborne and/or PM10 fraction to total wear is approximately 40-45% on average. - Non-asbestos organic (NAO) pads reduce emissions by an average of 62% for PM10, 55% for PM2.5, and 64% for PN compared to ECE pads. - Carbon-ceramic (CC) and hard metal coated (HMC) discs reduce PM10 by 81% and 57%, and PM2.5 by 74% and 60%, respectively. - Brake particle filters have an average PM efficiency of 50% for passive systems and 75% for active systems. - Electrified vehicles are expected to have lower brake emissions due to regenerative braking, but their mass increases by 15-25%. The emission factors are compared with roadside measurements and emission inventories, showing good agreement. The study concludes that the findings can be used to estimate the contribution of brakes to air pollution in emission inventories.