Wash. Admin. Code § 296-876-40040
(3) You must use a safety belt with a lanyard that is secured to the ladder when doing any work that:
[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060, and chapter 49.17 RCW. WSR 14-09-095, § 296-876-40040, filed 4/22/14, effective 7/1/14. Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060. WSR 05-20-068, § 296-876-40040, filed 10/4/05, effective 1/1/06.]