(1) "Special highway construction equipment" means any vehicle that is (a) designed and used primarily for the grading of highways, the paving of highways, earthmoving, and other construction work on highways, (b) not designed or used primarily to transport persons or property on a public highway, and (c) only incidentally operated or moved over the highway.
(2) "Special highway construction equipment" includes, but is not limited to, road construction and maintenance machinery that is designed and used for the purposes described under subsection (1) of this section, such as portable air compressors, air drills, asphalt spreaders, bituminous mixers, bucket loaders, track laying tractors, ditchers, leveling graders, finishing machines, motor graders, paving mixers, road rollers, scarifiers, earthmoving scrapers and carryalls, lighting plants, welders, pumps, power shovels and draglines, and self-propelled and tractor-drawn earthmoving equipment and machinery, including dump trucks and tractor-dump trailer combinations that (a) are in excess of the legal width, (b) because of their length, height, or unladen weight, may not be moved on a public highway without the permit specified in RCW
46.44.090 and are not operated laden except within the boundaries of the project limits as defined by the contract, and other similar types of construction equipment, or (c) are driven or moved upon a public highway only for the purpose of crossing the highway from one property to another, provided that the movement does not exceed five hundred feet and the vehicle is equipped with wheels or pads that will not damage the roadway surface.