Wash. Rev. Code § 88.16.180
Notwithstanding the provisions of RCW 88.16.070, any registered oil tanker of five thousand gross tons or greater, shall be required:
[ 1991 c 200 s 602; 1983 c 3 s 231; 1975 1st ex.s. c 125 s 2.]
Effective dates—1991 c 200: See RCW 90.56.901.
Severability—1975 1st ex.s. c 125: See notes following RCW 88.16.170.