LAUSR

Abstract This paper describes the Inspection and Maintenance Programs (I/M programs) for in-service vehicles adopted in Brazil. The study presents unpublished and long-term data obtained in Rio de Janeiro state (RJ), Brazil, one of the few states to comply with the program. The objective was to evaluate the relationship between I/M programs and the air pollutant levels in RJ, considering a peculiar fleet with flex-fuel vehicles and fossil fuel/biofuel mixtures. Data from 2014 to 2017 was used for this purpose. Results show that the lack of maintenance of the vehicles is an important source of air pollution since carbon monoxide (CO) and hydrocarbon (HC) levels increased up to 5 times compared to national limits. A considerable part of the light-vehicles (30 %) failed during annual inspections. The vehicles, which failed, emitted up to 12 times more pollutants than the approved ones. I/M programs are very effective tools to reduce air pollutant levels and should be implemented and improved in order to get better air quality, making cities more sustainable.