Washington Revised Code Title 46. Motor Vehicles § 46.44.043. Cement trucks--Axle loading controls

The switch that controls the raising and lowering of the retractable rear booster or tag axle on a ready-mix cement truck may be located within the reach of the driver's compartment as long as the variable control, used to adjust axle loadings by regulating air pressure or by other means, is out of the reach of the driver's compartment.