Wash. Rev. Code § 49.46.120
This chapter establishes minimum standards for wages, paid sick leave, and working conditions of all employees in this state, unless exempted herefrom, and is in addition to and supplementary to any other federal, state, or local law or ordinance, or any rule or regulation issued thereunder. Any standards relating to wages, hours, paid sick leave, or other working conditions established by any applicable federal, state, or local law or ordinance, or any rule or regulation issued thereunder, which are more favorable to employees than the minimum standards applicable under this chapter, or any rule or regulation issued hereunder, shall not be affected by this chapter and such other laws, or rules or regulations, shall be in full force and effect and may be enforced as provided by law.
RCW 49.46.120
Intent-Effective date- 2017 c 2 (Initiative Measure No. 1433): See notes following RCW 49.46.005.