NAC445B.7665. Standards of opacity; citation for violation; equipment for measurement.

     1. Except as otherwise provided in this section and NAC 445B.774, no owner or driver of a heavy-duty motor vehicle powered by:

     (a) A 1991 or newer model-year engine may cause or permit the discharge into the atmosphere of engine exhaust from the vehicle which is of an opacity greater than 40 percent.

     (b) A 1977 to 1990 model-year engine may cause or permit the discharge into the atmosphere of engine exhaust from the vehicle which is of an opacity greater than 55 percent.

     (c) A 1970 to 1976 model-year engine may cause or permit the discharge into the atmosphere of engine exhaust from the vehicle which is of an opacity greater than 70 percent.

     2. A vehicle will not be cited as violating any smoke opacity standard listed in subsection 1 unless the opacity reading is at least 1 full percentage point greater than the relevant standard.

     3. Before July 1, 2003, the Director may authorize opacity testing that uses equipment for the measurement of smoke opacity without the built-in capability to adjust the opacity readings to take ambient conditions into consideration as required by the Society of Automotive Engineers Procedure, SAE J1667, “Snap-Acceleration Smoke Test Procedure for Heavy-Duty Diesel Powered Vehicles.” If the smoke opacity of a heavy-duty motor vehicle is tested using equipment authorized for use by the Director pursuant to this subsection, the owner or driver of a heavy-duty motor vehicle is not in violation of the provisions of subsection 1 unless the discharge into the atmosphere of engine exhaust is of an opacity greater than 70 percent. On and after July 1, 2003, only equipment that has the built-in capability to adjust the opacity readings to take ambient conditions into consideration as required by the Society of Automotive Engineers Procedure, SAE J1667, “Snap-Acceleration Smoke Test Procedure for Heavy-Duty Diesel Powered Vehicles,” may be used to measure smoke opacity.

     4. A family of engines that has been exempted by the California Air Resources Board pursuant to section 2182(b) of Title 13 of the California Code of Regulations is not subject to the standards set forth in subsection 1. Such a family of engines is subject to the technologically appropriate less stringent opacity standard identified by the Executive Director of the California Air Resources Board pursuant to section 2182(b) of Title 13 of the California Code of Regulations for that family of engines, plus 5 percentage points.

     (Added to NAC by Environmental Comm’n, 5-3-96, eff. 7-1-96; A by R102-02, 10-18-2002)