Wash. Rev. Code § 35.21.768
The legislative authority of any city or town is authorized to adopt ordinances for the levy and collection of excise taxes and/or for the imposition of an additional tax for the act or privilege of engaging in the ambulance business. Such business and occupation tax shall be imposed in such amounts as fixed and determined by the legislative authority.
The excise taxes other than the business and occupation tax authorized by this section shall be levied and collected from all persons, businesses, and industries who are served and billed for said ambulance service owned and operated or contracted for by the city or town in such amounts as shall be fixed and determined by the legislative authority of the city or town.
All taxes authorized pursuant to this section shall be construed to be taxes other than a retail sales tax defined in chapter 82.08 RCW and a use tax defined in chapter 82.12 RCW, and the city or town shall appropriate and use the proceeds derived from all taxes authorized by this section only for the operation, maintenance and capital needs of its municipally owned, operated, leased or contracted for ambulance service.
RCW 35.21.768