COSTS AND BENEFITS OF VEHICLE INSPECTION - A CASE-STUDY OF THE MARYLAND REGION

Vehicle emission inspection programs, as required by the Clean Air Act amendments of 1977, are now in place in over 40 regions of the U.S. Their purpose is to reduce the in-use emissions of vehicles, and hence to improve air quality and provide health and other economic benefits. We examine the full social costs and benefits for a representative emission inspection program, the Maryland program in the Baltimore/Washington corridor. Using data from a survey of drivers, we are able to estimate the full social costs of the program. We also estimate the joint reduction of both carbon monoxide and hydrocarbon (HC) pollution and the resulting benefits. Both cost-effectiveness and cost-benefit analyses are performed. We find the costs to be many times higher than a reasonable measure of the benefits in the Maryland region. Also, the costs are high relative to the cost of reducing pollution from other sources. We simulate some modifications to the Maryland program to determine ways to make it more cost-effective. Extending the inspection to include older vehicles, and increasing the repair limit for the waiver policy would improve the efficiency of the program. © 1990.