Environmental Gains through Air Quality Control in Brazil

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In Brazil, the battle against vehicular pollution took a significant leap in 1986 with the initiation of the Motor Vehicle Air Pollution Control Program (Proconve) by the National Environment Council (Conama). Managed by the Brazilian Institute for the Environment and Renewable Natural Resources (Ibama), Proconve has become a pivotal tool for controlling emissions from mobile sources in the country.


Proconve’s primary objective is to curtail pollutants emitted by various vehicles, including light vehicles (cars, pickups, vans), heavy vehicles (buses, trucks), and even agricultural and construction machinery. Additionally, the program aims to foster technological development in the national industry and enhance fuel quality, ultimately contributing to cleaner air.

Phases of Proconve

Proconve operates through distinct phases, each setting progressively stringent parameters for pollutants and introducing tests to verify emissions. For heavy vehicles, eight phases have been completed so far, showcasing Brazil’s commitment to environmental responsibility.

  1. P1 (1987): Focused on controlling smoke emissions from trucks and urban buses.
  2. P2 (1994): Introduced limits for major combustion engine pollutants, along with noise limits during acceleration and idle states. Also marked the implementation of engine air intake cooling systems.
  3. P3 (1996): Lowered emission limits and improved fuels by reducing sulfur content, necessitating adaptations by vehicle manufacturers.
  4. P4 (2000): Required 80% of vehicles from 2002 onwards to meet Proconve standards, further reducing emissions.
  5. P5 (2004): Tightened emission limits, prompting significant changes in engine design, including electronic fuel injection and the use of turbo and intercooler systems.
  6. P6 (2009): Unique in requiring not only engine and fuel system upgrades but also a lower sulfur content in fuel, a condition not met at the time.
  7. P7 (2012-2021): Focused on reducing nitrogen oxide (NOx) emissions, introducing the Selective Catalytic Reduction (SCR) system and ARLA 32 solution to achieve up to 98% NOx reduction.
  8. P8 (2022 onwards): Emphasizes proving emissions durability for heavy vehicles, requiring compliance for up to 700,000 kilometers.

Environmental Impact and Achievements

Since the inception of Proconve, Brazil has witnessed several noteworthy outcomes:

  1. Up to 98% reduction in pollutant emissions despite an increase in the vehicle fleet.
  2. Improved air quality in major cities.
  3. Modernization and diversification of the national automotive industry.
  4. Adoption, updating, and development of new technologies.
  5. Enhanced quality of automotive fuels.
  6. Creation of highly specialized professionals.
  7. Attraction of new investments, industries, and emission laboratories.

Current Phases and Categories

Presently, the active phases for different automotive categories are MAR-1 for agricultural and road machinery (since January 1, 2015), L-7 for light vehicles, and P-8 for heavy vehicles (from January 1, 2022).

Promot: A Companion Program

The Programa de Controle da Poluição do Ar por Motociclos, Ciclomotores e Veículos Similares (Promot) focuses on controlling pollution from motorcycles and similar vehicles. Instituted by Conama in 2002, it operates in progressively restrictive phases, with the current phase being Promot-M4 in 2024 and transitioning to Promot-M5 from January 2025.


Proconve stands as a testament to Brazil’s commitment to environmental sustainability. The program’s evolution, from addressing smoke emissions to implementing cutting-edge technologies, has significantly contributed to cleaner air and a more environmentally responsible automotive industry. As the nation continues to navigate through Proconve’s phases, the trajectory towards a greener and healthier future remains promising.