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Enhanced Area BAR-97 Emissions Inspection System (EIS) Equipment

California's enhanced areas are regions that do not meet federal ozone health standards. The BAR-97 Emissions Inspection System (EIS) is required in all Smog Check stations located in Enhanced Areas, California's smoggiest regions.

The BAR-97 EIS tests vehicles under simulated driving conditions to detect oxides of nitrogen (NOx), hydrocarbons (HC), and carbon monoxide (CO) emissions. These are the major chemical components of smog.

The BAR-97 EIS consists of a 5-gas analyzer, additional hardware, software, a fuel cap tester and a dynamometer with safety restraints. The most distinctive component of the equipment is the dynamometer, a treadmill-like device that simulates driving conditions. When necessary, the BAR-97 EIS can perform the two-speed idle test on vehicles that cannot be physically tested on the dynamometer.

NOx Testing: NOx emissions are generated when the vehicle's engine is hot. These temperatures occur while the vehicle is being driven. Therefore, testing under simulated driving conditions is essential for measuring NOx emissions. This type of test is called Acceleration Simulation Mode (ASM). California began NOx testing because NOx is a key ingredient in ozone smog formation and NOx reductions are required under federal law by the U.S. Environmental Protection Agency.

Enhanced Area Vehicles: Only BAR-97 ASM tests are accepted in the Enhanced Smog Check Areas of the state.The only exceptions are for vehicles with full-time, four-wheel drive, all-wheel drive, traction control, and specified heavy duty trucks. These vehicles are tested in the two-speed idle mode.

Stations: All Smog Check stations in the Enhanced Areas, including Gold Shield, Test-Only, and Referee Centers, are required to have a BAR-97 EIS. Basic Area stations with Enhanced Area customers must use the BAR-97 EIS to test their vehicles.

Technician License: To operate the BAR-97 EIS, licensed Smog Check technicians must pass a comprehensive examination and obtain specified certifications from Automotive Service Excellence (ASE - A6, A8 & L1).

Other Uses: The BAR-97 EIS can be used as a diagnostic tool. Besides being able to diagnose emissions system problems, Smog Check technicians can use the dynamometer to quickly pinpoint abnormalities that occur when the vehicle is being driven, such as transmission problems.

California Department of Consumer Affairs Hotline 1 (800) 952-5210