For the purpose of the Washington state public works law, chapter 39.12 RCW, ready mix truck drivers drive transit mixer and volumetric type trucks used for the transportation of wet concrete products to, from, and on construction projects, consistent with the provisions in WAC 296-127-018.
The work includes, but is not limited to, the use of any transit mixer or volumetric type truck used to deliver wet concrete.
Wash. Admin. Code § 296-127-01366