Auto inspection programs are required for some polluted areas. These periodic inspections, usually done once a year or once every two years, check whether a car is being maintained to keep pollution down and whether emission control systems are working properly. Vehicles which do not pass inspection must be repaired. As of 1992, 111 urban areas in 35 states already had I/M programs. Under the 1990 Clean Air Act, some especially polluted areas will have to have enhanced inspection and maintenance programs, using special machines that can check for such things as how much pollution a car produces during actual driving conditions.
INSPECTION AND MAINTENANCE PROGRAM (I/M PROGRAM)
Meaning of INSPECTION AND MAINTENANCE PROGRAM (I/M PROGRAM) in English
Environmental engineering English vocabulary. Английский словарь экологического инжиниринга. 2012