Once you have obtained approval as a state-plan manufacturer:
Wash. Admin. Code § 296-150R-0310
Statutory Authority: RCW 43.22.340, [43.22.]355, [43.22.]360, [43.22.]432, [43.22.]440 and [43.22.]480. 96-21-146, § 296-150R-0310, filed 10/23/96, effective 11/25/96.