PDFWAC 173-421-100
Emission control systems.
A person shall not remove or render inoperable any component or change any element of design of a motor vehicle including adjustments outside the range of manufacturer's specifications that could affect the amount of air contaminants emitted from that vehicle subject to the following conditions:
(1) Components of emission control systems may be disassembled and assembled for the purpose of repair and maintenance. These components or elements of design shall be restored to proper working order when they are repaired or maintained.
(2) When components of emission control systems require replacement they may be removed and replaced with a part intended by the vehicle manufacturer as a replacement part for that specific vehicle. Under circumstances established by the United States Environmental Protection Agency, an aftermarket replacement part may be used. A replaced part shall be installed and adjusted so that it is in proper working order.
[Statutory Authority: Chapter 70.94 RCW. WSR 87-19-078 (Order 87-17), ยง 173-421-100, filed 9/16/87.]