As used in this chapter, the following words mean:

(1) "Bicycle." A vehicle with two wheels in tandem usually propelled by pedals connected to the rear wheel by a chain and having handlebars for steering. The term bicycle is intended to include other pedal-powered cycles.

(2) "Electric personal assistive mobility device (EPAMD)." A self-balancing device with two wheels not in tandem, designed to transport only one person by an electric propulsion system with an average power of seven hundred fifty watts (one horsepower) having a maximum speed on a paved level surface, when powered solely by such a propulsion system while ridden by an operator weighing one hundred seventy pounds, of less than twenty miles per hour. This term is intended to include other similar devices as defined in RCW 46.04.304 as now or hereafter amended.

(3) "Moped." A motorized device designed to travel with not more than three sixteen-inch or larger diameter wheels in contact with the ground, having fully operative pedals for propulsion by human power, and an electric or a liquid fuel motor with a cylinder displacement not exceeding fifty cubic centimeters that produces no more than two gross brake horsepower as defined in RCW 46.04.304 as now or hereafter amended.

(4) "Motorized foot scooter." A device with no more than two ten-inch or smaller diameter wheels that has handlebars, is designed to be stood or sat upon by the operator, and is powered by an internal combustion engine or electric motor that is capable of propelling the device with or without human propulsion, as defined in RCW 46.04.336 as now or hereafter amended.

(5) "Other powered devices." A device that transports people powered by electric and/or combustion motors except for those licensed under state law for highway use.

(6) "Pedestrian." Any person who is afoot or who is using a wheelchair, a powered wheelchair or a powered scooter for persons with disabilities.

(7) "Walk zone." Any area designated by signs or symbols as a place where bicycles, skateboards, and other regulated devices cannot be ridden during specified periods.