Washington Revised Code Title 51. Industrial Insurance § 51.28.040. Application for change in compensation

(1)(a) If change of circumstances warrants an increase or rearrangement of compensation, like application shall be made therefor. Where the application has been granted, compensation and other benefits if in order shall be allowed for periods of time up to 60 days prior to the receipt of such application, except as provided in (b) of this subsection.

(b) Compensation and other benefits under (a) of this subsection shall be allowed for periods of time beyond 60 days, up to and including the time period covering the change of circumstances warranting an increase or rearrangement of compensation or other benefits, subject to a maximum of 120 days prior to the receipt of the application, where:

(a) Encourage the worker to submit the form to the treating provider within 30 days of the provision of any medical services made necessary by the change in circumstances; and

(b) Provide notice to both the worker and the medical provider that the application must be received by the department or self-insurer within 60 days of the provision of any medical services made necessary by the change in circumstances.