(1) "Chief" means the chief of the Washington state patrol or their designee.

(2) "Private carrier bus" means every motor vehicle designed for the purpose of carrying passengers used regularly to transport persons in furtherance of any organized agricultural, religious, or charitable purpose, and having a seating capacity for:

(a) Eight passengers if the transportation is provided for compensation; or

(b) Fifteen passengers if the transportation is provided not for compensation.

Such term does not include buses operated by common carriers under a franchise granted by any city or town or the Washington public utilities commission.

(3) "Stop signal" means a sign bearing the word "stop" which is actuated by the driver of the bus.

(4) "Signal lamps" means red lamps mounted on the vehicle to be used in conjunction with the "stop signal" when the bus is loading or unloading passengers under certain conditions.

(5) "Warning sign" means a sign to be attached to the rear of the bus to inform following motorists of their duty to stop when the "signal lamps" are activated.

The signal lamps required on private carrier buses must be constructed in conformance with the society of automotive engineers standard for "school bus red signal lamps," in effect at the time of manufacture of such lamps. All lamps used as signal lamps must meet the requirements set forth for lighting under chapter 204-21 WAC.

The stop signal required on private carrier buses must:

(1) Be fourteen inches vertically and eighteen inches horizontally.

(2) Be treated with red reflective material.

(3) Have the word "stop" painted on the sign in white with letters which are a minimum of eight inches in height and having a three-quarter-inch stroke.

(4) Meet the requirements outlined in above on both sides of the sign.

(5) Be mounted on the left side of the bus just below the window line and adjacent to the driver of the bus.

(6) Be hinged at the front edge of the sign.

(7) Be manually controlled by the driver of the bus.

(8) Be so constructed as to lock in an extended position perpendicular to the side of the bus and to also lock in the closed position parallel to the side of the bus.

(9) Only be actuated by the driver of a private carrier bus whenever such vehicle is stopped on the highway for the purpose of receiving or discharging passengers, except:

(a) When the passengers boarding or alighting do not have to cross a highway and the bus is stopped completely off the main traveled portion of the roadway; or

(b) When the bus is stopped at an intersection or place where traffic is controlled by a traffic officer or official control signal.

A sign must be affixed to every private carrier bus that is plainly visible and contains the words "private carrier bus." The sign must:

(1) Have letters not less than eight inches in height.

(2) Have letters that are at least three-quarter-inch stroke.

(3) Be located above the windshield on the front of the bus and above the rear windows on the rear of the bus.

A sign must be affixed to the rear of every private carrier bus that is clearly visible and contains the words "unlawful to pass bus when red lights flash." The sign must:

(1) Be sixteen inches vertically and thirty-two inches horizontally.

(2) Have a background of silver retrodirective-reflex reflective sheeting.

(3) Have lettering that is size three inch B.

(4) Have the letters "unlawful to" in black on line one.

(5) Have the letters "pass bus when" in black on line two.

(6) Have the letters "red lights flash" in red on line three.

(1) The driver of any private carrier bus, carrying any passenger, before crossing at grade any track or tracks of a railroad, must stop such vehicle within fifty feet but no less than fifteen feet from the nearest rail of such railroad and while so stopped must listen and look in both directions along such track for any approaching train, and for signals indicating the approach of a train and must not proceed until he can do so safely.

(2) After stopping as required and upon proceeding when it is safe to do so the driver of any private carrier bus must cross only in such gear of the vehicle that there will be no necessity for changing gears while traversing such crossing and the driver must not shift gears while crossing the track or tracks.

(3) No stop need be made at any such crossing where a police officer or a traffic-control signal directs traffic to proceed.

The chief may, from time to time, require that every private carrier bus be presented at some location which must be designated by him for the purpose of inspection of the vehicle to determine if the vehicle is equipped as required by law and the provisions of this regulation.

The chief may delegate officers of the Washington state patrol to work with private carrier bus operators and owners to establish routes and passenger loading and unloading locations which will provide the greatest safety for bus passengers and the motoring public. Bus stops and routes established by this means must be adhered to by private carrier bus drivers.