This paper presents a comprehensive overview of Brazilian On-Board Diagnostic (OBD) regulations, Inspection and Maintenance (I/M) Programs and Aftermarket Catalyst regulations as well as an overview of similar regulations in the United States and Europe. Opportunities and technical risks are described in this context.
Regulatory information contained in this Paper is intended to serve as reference only. Updated and complete rules and regulations must be used for official purposes.
The implementation of the second stage of Brazilian OBD (OBDBr-2), starting in 2010, represents a significant improvement towards exhaust emission control and on-board diagnostic monitoring. Its effectiveness and credibility will be heavily influenced by how this new technology is integrated into I/M programs and how well it meshes with aftermarket catalyst regulations. Currently, Brazilian I/M regulations do not incorporate any OBD requirements and only Rio de Janeiro State has implemented an I/M Program. In the absence of an effective I/M program, emission controls tampering can go undetected (e.g. aftermarket catalysts with no ceramic substrate inside).
Having OBD checks integrated into an I/M program is an important factor that should be considered in the next stages of Brazilian emission control programs. The US EPA completely replaced traditional tailpipe exhaust tests with OBD checks. EPA experience, however, has shown that it takes a long time to roll out a credible I/M regulation because its credibility strongly depends on the correlation between OBD checks and I/M tailpipe exhaust tests.
Finally, it should be pointed out that to work effectively in an I/M program, OBD requirements need to consider the vehicle population as a whole and include spark-ignition and compression-ignition engines, aftermarket catalysts as well as various evaporative and exhaust emission controls.