NAC445B.589. Testing of certain motor vehicles powered by diesel engines: Procedure; certificate of compliance; effect of failure; lack of proper fuel cap.  


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  •      1. An inspector shall comply with the following procedure when testing a light-duty motor vehicle that is powered by a diesel engine or a heavy-duty motor vehicle that is powered by a diesel engine and has a manufacturer’s gross vehicle weight rating which does not exceed 14,000 pounds:

         (a) The test procedure must include, without limitation, a preparation phase, a tampering inspection phase and an opacity test phase.

         (b) In the preparation phase:

              (1) The vehicle must be placed on a dynamometer, the transmission must be placed in neutral and the vehicle must be properly restrained to prevent any rolling motion.

              (2) The inspector may place an auxiliary cooling fan into position approximately 12 inches in front of the cooling system of the motor vehicle.

              (3) The inspector shall then affix a smoke opacity meter which has been calibrated and zeroed to the exhaust system of the vehicle according to the recommendations of the manufacturer of the meter. Vehicles with dual exhaust configurations must have the smoke opacity meter attached to the exhaust pipe displaying the highest observed opacity.

              (4) If an exhaust removal system is used, it must be installed so that all of the exhaust from the vehicle being tested is passed through the smoke opacity meter.

         (c) In the tampering inspection phase, the inspector shall visually inspect:

              (1) All vehicles with a model year of 1981 or newer to ensure that all equipment for emission control which is listed on the manufacturer’s emission label is present and appears to be operational; and

              (2) All vehicles to verify the presence of a properly installed fuel cap.

         (d) During the opacity test phase, the inspector shall:

              (1) Verify that the vehicle is at normal operating temperature before beginning the test. If the vehicle has cooled down below its normal operating temperature during its placement on the dynamometer, it must be operated until its normal operating temperature is reached.

              (2) Test vehicles with varying engine sizes under the following speed and load conditions:

    Speed

    Load

    Number of Cylinders

    (± 4 miles per hour)

    (± 1 horsepower)

    4

    40

    7.0

    6

    40

    15.0

    8

    40

    30.0

              (3) Maintain the required speed and load condition on the vehicle being tested for 10 seconds. The engine opacity must be stored and printed at the end of the 10-second interval.

         2. The inspector shall issue a certificate of compliance indicating the results of the test. The printout from the opacity meter must be provided with the certificate of compliance. The test is complete if the vehicle passes the tampering inspection phase and the results of the opacity test phase comply with the standards set forth in NAC 445B.576. A vehicle which exceeds the opacity standards or which fails the tampering inspection phase must be considered to have failed the inspection, and the inspector shall issue a certificate of compliance reflecting the failure.

         3. A vehicle which fails the tampering inspection phase or the opacity test must be repaired and retested.

         4. If a motor vehicle subject to the provisions of this section passes all portions of an inspection but has an improper fuel cap or no fuel cap, the owner or operator of the motor vehicle shall obtain a fuel cap which is in accordance with the specifications of the manufacturer of the vehicle. The inspector shall inspect the new fuel cap and certify its presence in a manner prescribed by the Department, and sign and date the failing vehicle inspection report beneath the fuel cap tamper description. Such a vehicle inspection report may be used as evidence of compliance.

     (Added to NAC by Dep’t of Motor Veh. & Pub. Safety, eff. 11-10-92; A by R079-98, 9-25-98; A by Dep’t of Motor Veh. by R068-05, 6-1-2006, eff. 9-1-2006; A by Environmental Comm’n by R130-09, 1-28-2010)