EPA Questions Value of Emissions Tests

Growing concern at the U.S. Environmental Protection Agency regarding the value and “fairness” of state-run inspection/maintenance (I/M) vehicle emissions testing programs has kicked off an internal EPA review, with new directions to be announced by late summer.

The EPA acknowledged in 1999 that the focus should be taken off the emissions testing process and instead put on “cleaning the air by whatever method makes the most sense.”

Greg Green, director of the EPA's Vehicle Certification and Compliance Section in Ann Arbor, MI, tells Ward's the emissions-reduction gains attributed to I/M programs are small — and declining annually because of the gradual turnover to new vehicles with more effective emissions-control systems.

He says the EPA also is increasingly concerned about the cost to repair older, complex-technology vehicles. State-run I/M programs, whether using tailpipe testing or data generated by the vehicle's onboard diagnostic (OBD) systems, require owners to have the vehicle repaired — often at considerable cost — in order to be driven legally.

Green acknowledges emissions tests that rely on OBD systems magnify motorist repair liability by signaling more “problems,” some of which are temporary. And older owners, who drive infrequently and seldom at speeds and loads adequate to clear catalysts from sulfur effects, are another group disproportionately impacted by emissions testing.

A spokesman for the Missouri AAA Motor Club says the impact of I/M on lower-income drivers must be viewed in context with the unfortunate fact that 30% to 50% of urban motorists don't carry legally required vehicle insurance, and there is a growing problem of stolen license plates and registration tags. The spokesman says expensive repair consequences of I/M programs effectively adds to the number of vehicles driven illegally.

While the EPA now is reacting to the situation and shows concern for the social consequences of expensive emissions-related repairs, states with emissions-test programs are finding it difficult to adjust.

One example is Illinois. Its EPA office recently issued a forecast (state implementation plan) for vehicle pollution reduction. But in a document obtained by Ward's, Illinois' SIP does not outline its I/M programs' actual contribution to pollution reduction.

Meanwhile, the EPA's latest computer-modeled estimates (M6) indicate that in a typical urban area, about 95% of vehicle hydrocarbon reduction can be attributed to ongoing vehicle technology improvements — and just 5% to I/M programs. The data has led one researcher to label emissions-testing programs as “irrelevant.”