S-1988

AN ACT Relating to noise prevention for motor vehicles; and amending RCW 46.37.390.

BE IT ENACTED BY THE LEGISLATURE OF THE STATE OF WASHINGTON:

Sec. 1. RCW 46.37.390 and 1977 ex.s. c 355 s 33 are each amended to read as follows:

(1) Every motor vehicle shall at all times be equipped with a muffler in good working order and in constant operation to prevent excessive or unusual noise, and no person shall use a muffler cut-out, bypass, or similar device upon a motor vehicle on a highway.

(2)(a) No motor vehicle first sold and registered as a new motor vehicle on or after January 1, 1971, shall discharge into the atmosphere at elevations of less than three thousand feet any air contaminant for a period of more than ten seconds which is:

(i) As dark as or darker than the shade designated as No. 1 on the Ringelmann chart, as published by the United States bureau of mines; or

(ii) Of such opacity as to obscure an observer's view to a degree equal to or greater than does smoke described in subsection (a)(i) above.

(b) No motor vehicle first sold and registered prior to January 1, 1971, shall discharge into the atmosphere at elevations of less than three thousand feet any air contaminant for a period of more than ten seconds which is:

(i) As dark as or darker than the shade designated as No. 2 on the Ringelmann chart, as published by the United States bureau of mines; or

(ii) Of such opacity as to obscure an observer's view to a degree equal to or greater than does smoke described in subsection (b)(i) above.

(i) "Opacity" means the degree to which an emission reduces the transmission of light and obscures the view of an object in the background;

(ii) "Ringelmann chart" means the Ringelmann smoke chart with instructions for use as published by the United States bureau of mines in May 1967 and as thereafter amended, information circular 7718.

(3) No person shall modify the exhaust system of a motor vehicle in a manner ((which will amplify or increase the noise emitted by the engine of such vehicle above that emitted by the muffler originally installed on the vehicle, and it shall be unlawful for any person to operate a motor vehicle not equipped as required by this subsection, or which has been amplified as prohibited by this subsection)) so that the vehicle's noise exceeds eighty-six decibels on the "A" scale at fifty feet as measured by the Society of Automotive Engineers (SAE) test procedure J 331a, except that a maximum noise level of one hundred five decibels on the "A" scale at a distance of twenty inches from the exhaust outlet is an acceptable substitute in lieu of the Society of Automotive Engineers test procedure J 331a when measured:

(a) At a forty-five degree angle at a distance of twenty inches from the exhaust outlet;

(b) With the vehicle stationary and the engine running at a steady speed equal to one-half of the manufacturer's maximum allowable ("red line") engine speed or where the manufacturer's maximum allowable engine speed is not known the test speed in revolutions per minute calculated as sixty percent of the speed at which maximum horsepower is developed; and

(c) With the microphone placed ten inches from the side of the vehicle, one-half way between the lowest part of the vehicle body and the ground plane, and in the same lateral plane as the rearmost exhaust outlet where the outlet of the exhaust pipe is under the vehicle.

This subsection (3) does not apply to passenger vehicles being operated off the highways in an organized racing or competitive event conducted by a recognized sanctioning body.