Section 1200-03-29-.07 - MOTOR VEHICLE EMISSIONS PERFORMANCE TEST METHODS(1) For gasoline powered motor vehicles, the motor vehicle emissions performance test shall consist of the sampling of exhaust emissions at idle speed and measurement of CO2 dilution, CO concentration and HC concentration.(2) For gasoline powered motor vehicles, sampling of exhaust emissions shall consist of measurement of CO2 dilution, CO concentration and HC concentration during idle operation using an approved exhaust gas analyzer. Measurements taken during the initial idle phase may be succeeded by measurements taken during a second idle phase which has followed an engine conditioning phase consisting of engine operation at approximately 2500 RPM for approximately 20 seconds. The lowest emission readings from either of these idle speed test phases shall be used to determine pass or failure of the emissions performance test.(3) For diesel powered motor vehicles, the motor vehicle emissions performance test shall consist of the Curb Idle test procedures for diesel vehicles: (a) Diesel-powered vehicles shall be inspected with an opacity meter that is a full-flow, direct reading, continuous reading light extinction type using a collimated light source and photo-electric cell, accurate to within plus or minus five (5) percent.(b) Separate measurements shall be made on each exhaust outlet on diesel vehicles equipped with multiple exhaust outlets. The reading taken from the outlet giving the highest reading shall be used for comparison with the standard for the vehicle being tested.(4) For gasoline powered motor vehicles with a model year of 1996 and newer and for diesel powered motor vehicles with a model year of 2002 and newer, an onboard diagnostic test shall be performed. All vehicles that have a readily accessible OBD system shall be tested. The results of the test shall be used to determine pass or failure of the vehicle.Tenn. Comp. R. & Regs. 1200-03-29-.07
Original rule filed February 14, 1994; effective April 30, 1994. Stay of effective date filed April 15, 1994; effective June 14, 1994. Amendment filed September 19, 2001; effective December 3, 2001. Repeal and new rule filed September 28, 2004; effective December 12, 2004.Authority: T.C.A. §§ 68-201-105 and 4-5-201 et. seq.