206-2 Wyo. Code R. § 2-5

Current through April 27, 2019
Section 2-5 - Bus Chassis Standards

(a) AIR CLEANER.

  • (i) The engine intake air cleaner system shall be furnished and properly installed by the chassis manufacturer to meet engine manufacturer's specifications.
  • (ii) The intake air system for diesel engines having an air cleaner restriction indicator shall be properly installed by the chassis manufacturer to meet above specifications.

(b) AXLES. The front and rear axle and suspension systems shall have gross axle weight rating at ground commensurate with the respective front and rear weight loads that will be imposed by the bus.

(c) BRAKES.

  • (i) All braking systems shall comply with applicable Federal Motor Vehicle Safety Standards,
  • (ii) The brake lines and booster-assist lines shall be protected from excessive heat and vibration and installed in a manner that prevents chafing,
  • (iii) All brake systems shall be designed to permit visual inspection of brake lining wear without removal of any chassis components,
  • (iv) All Type C and D buses shall have air brakes. All air brakes systems shall have heated automatic drain on the wet tank, (except for Type C 30 passenger, which may have hydraulic brakes).
  • (v) All air brake systems shall be equipped with an air dryer,

(d) BUMPER (Front).

  • (i) All school buses shall be equipped with a front bumper. The front bumper shall be of pressed steel channel or equivalent material at least 3/16" thick and not less than 8" wide (high) and shall extend beyond forward-most part of the body grille, hood and fenders and shall extend to outer edges of the fenders at the bumper's top line. Type A buses may use the manufacture's standard bumper. On a Type D school bus, if the chassis manufacturer does not provide a bumper, the body manufacturer shall provide it,
  • (ii) Front bumper, except breakaway bumper ends, shall be of sufficient strength to permit pushing a vehicle of equal gross vehicle weight without permanent distortion to the bumper, chassis, or body on a level surface,
  • (iii) Tow eyes or hooks shall be furnished and attached so as not to project beyond the front bumper. Type A under 14,001 pounds. GVWR are exempt.
  • (iv) The bumper shall be designed or reinforced so that it will not deform when the bus is lifted by a chain that is passed under the bumper (or through the bumper if holes are provided for this purpose) and attached to both tow eyes. For the purpose of meeting this standard, the bus shall be empty and positioned on a level, hard surface and both tow eyes shall share the load equally.

(e) CERTIFICATION, By December 31 of each year, each chassis manufacturer shall certify to the Wyoming Department of Education that their product meets minimum standards on items not covered by certification issued under requirements of the National Traffic and Motor Vehicle Safety Act,

(f) COLOR.

  • (i) Chassis, including front bumper, shall be black. Body cowl, hood and fenders shall be in National School Bus Yellow. The flat top surface of the hood may be non-reflective National School Bus Yellow,
  • (ii) Wheels may be silver, gray or black as received from the wheel manufacturer.

(g) DRIVE SHAFT. Drive shaft shall be protected by a metal guard or guards around the circumference of the drive shaft to reduce the possibility of its whipping through the floor or dropping to the ground if broken,

  • (i) ELECTRICAL SYSTEM. The electrical system shall include the following:

(h) Battery

  • (A) Storage battery shall have minimum cold cranking capacity rating equal to the cranking current required for 3 0 seconds at 0 degrees Fahrenheit (-17. 8°C) and a minimum reserve capacity rating of 120 minutes at 25 amps. Higher capacities may be required depending upon equipment and local environmental conditions.
  • (B) Type C bus to have three Group 31 maintenance free batteries. Type D to have two 8D maintenance free batteries,
    • (i) Alternator
      • (A) All Type A-1 buses shall have a minimum 130-ampere alternator.
      • (B) All Type A-II, B, C and D buses shall be equipped with a heavy-duty truck or bus-type alternator, having a minimum output rating of 130 amperes.
      • (C) All buses equipped with an electrical power lift shall have a minimum 200-ampere alternator.
      • (D) Direct drive alternator is permissible in lieu of belt drive. Belt drive shall be capable of handling the rated capacity of the alternator with no detrimental effect on other driven components.
      • (E) Refer to SBMTC Design Objectives, 1990 edition for estimating required alternator capacity,
    • (ii) Wiring
      • (A) All wiring shall conform to current applicable recommended practices of the Society of Automotive Engineers (SAE).
        • (I) All wiring shall use a standard color and number coding and each chassis shall be delivered with a wiring diagram that illustrates the wiring of the chassis.
      • (B) Chassis manufacturer shall install a readily accessible terminal strip or plug on the body side of the cowl, or in an accessible location in the engine compartment of vehicles designed without a cowl, that shall contain the following terminals for the body connections:
        • (I) Main 100 amp body circuit
        • (II) Tail lamps
        • (III) Right turn signal
        • (IV) Left turn signal
        • (V) Stop lamps
        • (VI) Back up lamps
        • (VII) Instrument panel lights shall be rheostat controlled
    • (iii) Circuits
      • (A) An appropriate identifying diagram (color and number coded) for electrical circuits shall be provided to the body manufacturer for distribution to the end user.
      • (B) Headlight system shall be wired separately from the body-controlled solenoid.

(i) ENGINES:

  • (i) All engines shall be equipped with engine block heater,
  • (ii) All engines shall be supplied with Long Life coolant,
  • (iii) All engines shall be equipped with cruise control.

(j) EXHAUST SYSTEM,

  • (i) Exhaust pipe, muffler and tailpipe shall be outside the bus body compartment and attached to the chassis so as not to damage any other chassis component.
  • (ii) Tailpipe shall be constructed of a corrosion-resistant tubing material at least equal in strength and durability to 16-gauge steel tubing. Type A under 14,001 lbs. GVWR are exempt,
  • (iii) Chassis manufacturers shall furnish an exhaust system with tailpipe of sufficient length to exit the rear of the bus or at the left side of the bus body no more than 18" forward of the front edge of the rear wheelhouse opening. If designed to exit at the rear of the bus, the tailpipe shall extend at least five inches beyond the end of the chassis frame. If designed to exit to the side of the bus, the tailpipe shall extend at least 48.5 inches (51,5 inches if the body is to be 102" inches wide) outboard from the chassis centerline.
    • (A) On all buses, the tailpipe shall not exit beneath a fuel fill, an emergency door exit, or a lift door
  • (iv) Exhaust system on a chassis shall be adequately insulated from the fuel system,
  • (iv) Muffler shall be constructed of corrosion-resistant material,

(k) FENDERS, FRONT-TYPE C VEHICLES.

  • (i) Total spread of outer edges of front fenders, measured at fender line, shall exceed total spread of front tires when front wheels are in straight-ahead position,
  • (ii) Front fenders shall be properly braced and free from any body attachments,

(l) FRAME.

  • (i) Frame or equivalent shall be of such design and strength characteristics as to correspond at least to standard practice for trucks of the same general load characteristics which are used for highway service.
  • (ii) Any secondary manufacturer that modifies the original chassis frame shall guarantee the performance of workmanship and materials resulting from such modification,
  • (iii) Frames shall not be modified for the purpose of extending the wheelbase,
  • (iv) Holes in top or bottom flanges or side units of the frame, and welding to the frame, shall not be permitted except as provided or accepted by chassis manufacturer,
  • (v) Frame lengths shall be provided in accordance with SBMTC Design Objectives, 1995 edition, except where body and chassis manufacturer are the same or have established mutual design criteria for the vehicle,

(m) FUEL TANK.

  • (i) The fuel tank shall be filled and vented to the outside of the body, in a location where accidental fuel spillage will not drip or drain on any part of the exhaust system. Type B and C shall have a minimum 60 gallon fuel tank. Type D buses shall have a minimum 100 gallon fuel tank, (Exception is Type C, 3 0 passenger bus will have a minimum 35 gallon fuel tank,)
  • (ii) No portion of the fuel system that is located outside the engine compartment, except the filler tube, shall extend above the top of the chassis frame rail, Fuel lines shall be mounted to obtain maximum possible protection from the chassis frame.
  • (iii) Fuel filter with replaceable element shall be installed between the fuel tank and engine.
  • (iv) Fuel tank installation shall be in accordance with SBMTC Design Objectives, 1990 edition, and all Federal Motor Vehicle Safety Standards in effect on the date of manufacture of the bus,
    • (A) Fuel tank(s) may be mounted between the chassis frame rails or outboard of the frame rails on either the left or right side of the vehicle,
  • (v) The actual draw capacity of each fuel tank shall be at least 83% of the tank capacity,
  • (vi) Unless specific agreement has been made between the body and chassis manufacturers, fuel tanks and filler spouts shall not be located in spaces restricted by SBMTC Design Objectives, 1990 edition,
  • (vii) Installation of alternative fuel systems, including fuel tanks and piping from tank to engine, shall comply with all applicable fire codes and applicable Federal Motor Vehicle Safety Standards in effect on the date of manufacture of the bus.
    • (A) Installation of LPG tanks shall comply with National Fire Protection Association (NFPA) 58.
  • (viii) All diesel fuel systems shall be equipped with a fuel heater and/or heated fuel-water separator.

(n) HEATING SYSTEM, PROVISION FOR.

  • (i) The chassis engine shall have plugged openings for the purpose of supplying hot water to the bus heating system. The openings shall be suitable for attaching 3/4-inch pipe thread/hose connector. The engine shall be capable of supplying water having a temperature of at least 170 degrees Fahrenheit at a flow rate of 50 pounds/per minute at the return end of 30 feet of one inch inside diameter automotive hot water heater hose, (SBMTC Standard No. 001--Standard Code for Testing and Rating Automotive Bus Hot Water Heating and Ventilating Equipment.)
  • (ii) Type A buses may meet manufacturer's standards.

(o) HORN. Bus shall be equipped with horn or horns of standard make with each horn capable of producing a complex sound in bands of audio frequencies between 250 and 2,000 cycles per second and tested in accordance with SAE J-377,

(p) INSTRUMENTS AND INSTRUMENT PANEL.

  • (i) Chassis shall be equipped with the following instruments and gauges, (Lights in lieu of gauges are not acceptable, except as noted):
    • (A) Hourmeter
    • (B) Speedometer
    • (C) Tachometer (Type C, D buses)
    • (D) Odometer that will give accrued mileage (to seven digits), including tenths of miles.
    • (E) Voltmeter
      • (I) Ammeter with graduated charge and discharge, with ammeter and its wiring compatible with generating capacities, is permitted in lieu of voltmeter.
    • (F) Oil pressure gauge
    • (G) Water temperature gauge
    • (H) Fuel gauge
    • (I) Upper beam headlight indicator (light)
    • (J) Brake indicator gauge (vacuum or air)
      • (I) Chassis with hydraulic assist brake systems shall be equipped with warning signals readily audible and visible to the driver, that will provide continuous warning in the event of a loss of fluid flow from the primary source or loss of electric power to the back-up system.
      • (II) Chassis with air brake system shall be equipped with visible gauge and audible low-pressure indicator to warn the driver if air pressure in the brake system falls below 60 PSI.
      • (III) Chassis with air brake system shall have a labeled visual indicator of park brake application visible to the driver.
    • (K) Turn signal indicators, (lights)
    • (L) Glow-plug indicator light where appropriate.
    • (M) Automatic Transmission temperature gauge (Type C and D buses).
  • (ii) All instruments shall be easily accessible for maintenance and repair.
  • (iii) Instruments and gauges shall be mounted on the instrument panel so that each is clearly visible to the driver while seated in a normal driving position in accordance with SBMTC Design Objectives, 1990 edition.
  • (iv) Instrument panel shall have lamps of sufficient candlepower to illuminate all instruments and gauges and shift selector indicator for automatic transmission.

(q) OIL FILTER. An oil filter with a replaceable element shall be provided and connected by flexible oil lines if not a built-in or an engine-mounted design.

(r) OPENINGS. All openings in the floorboard or firewall between chassis and passenger compartment, such as for gearshift selector and parking brake lever, shall be sealed.

(s) PASSENGER LOAD. Actual gross vehicle weight (GVW) is the sum of the chassis weight, plus the body weight, plus the driver's weight, plus total seated pupil weight.

  • (i) For purposes of calculation, the driver's weight is 150 pounds.
  • (ii) For purposes of calculation, the pupil weight is 120 pounds per pupil.
  • (iii) Actual gross vehicle weight (GVW) shall not exceed the chassis manufacturer's GVWR for the chassis nor shall the actual weight carried on any axle exceed the chassis manufacturer's gross axle weight rating (GAWR).

(t) POWER AND GRADEABILITY. GVWR shall not exceed 185 pounds per published net horsepower of the engine at the manufacturer's recommended maximum number of revolutions per minute.

(u) RETARDER SYSTEM (approved option-see Section 8 )

  • (i) A retarder is a device included within or attached to the engine, transmission or propeller shaft that will, upon demand, provide power to slow the vehicle on a downhill grade or assist the service brakes to stop the vehicle. Included is a hydraulic retarder in the automatic transmission or an electric or hydraulic retarder in the propeller shaft system.
  • (ii) Retarder system, if used, shall maintain the speed of the fully loaded school bus at 19.0 mph or 30 km/hr on a 7% grade for 3.6 miles or 6 km.
  • (iii) When a bus is equipped with a retarder the four stop lamps shall be illuminated when the retarder is activated.
  • (iv) The primary source activation of the retarder shall be a hand control. A foot control may be used in conjunction with the hand control. If a foot control is used, there must be a switch to deactivate the foot control during operation under icy conditions. Either control may activate the retarder separately.
  • (v) A bus equipped with a retarder shall have a pilot light to indicate when the retarder is in operation.
  • (vi) A bus equipped with an electro-magnetic retarder shall have controls that are solid state and interfaced with the vehicle's transmission, engine and the ABS brake system without degrading their operation or effectiveness.
  • (vii) Vehicles equipped with electromagnetic retarders shall have increased electrical capacity commensurate with the needs of the retarding system.

(v) SHOCK ABSORBERS. The bus shall be equipped with double-action shock absorbers compatible with manufacturer's rated axle capacity at each wheel location.

(w) SPRINGS.

  • (i) The capacity of springs or suspension assemblies shall be commensurate with chassis manufacturer's GAWR. Air suspension may be an approved option (see Section 8 ).
  • (ii) Front leaf springs shall have a stationary eye at one end and shall be protected by a wrapped leaf in addition to the main leaf.

(x) STEERING GEAR.

  • (i) The steering gear shall be approved by the chassis manufacturer and designed to ensure safe and accurate performance when the vehicle is operated with maximum load and at maximum speed.
  • (ii) If external adjustments are required, steering mechanism shall be accessible to accomplish it.
  • (iii) No changes shall be made in the steering apparatus that are not approved by the chassis manufacturer.
  • (iv) There shall be a clearance of at least 2 inches between the steering wheel and cowl, instrument panel, windshield, or any other surface.
  • (v) Power steering is required and shall be of the integral type with integral valves.
  • (vi) The steering system shall be designed to provide a means for lubrication of all wear-points, if wear-points are not permanently lubricated.
  • (vii) Tilt and/or telescoping steering column with padded steering wheel shall be provided.

(y) THROTTLE. The force required to operate the throttle shall not exceed 16 pounds throughout the full range of accelerator pedal travel.

(z) TIRES AND WHEELS.

  • (i) Tires and disc wheels of the proper size and tires with a load rating commensurate with chassis manufacturer's gross vehicle weight rating shall be provided. The use of multi-piece rims, cast spoke wheels and/or tube-type tires shall not be permitted.
  • (ii) Dual rear tires shall be provided on all school buses.
  • (iii) All tires on a vehicle shall be of the same size, and the load range of the tires shall meet or exceed the GVWR as required by FMVSS 120.
  • (iv) If the vehicle is equipped with a spare tire and wheel assembly, it shall be the same size as those mounted on the vehicle.
  • (v) If a tire carrier is required, it shall be suitably mounted in an accessible location outside the passenger compartment.

(aa) TRANSMISSION.

  • (i) Automatic transmissions shall have no fewer than three forward speeds and one reverse speed. The shift selector shall provide a detent between each gear position when the gear selector quadrant and shift selector are not steering column mounted, except for push button transmission selectors.
  • (ii) An electronic control or similar device may be installed to ensure that automatic transmissions cannot accidentally be moved out of the neutral or park gear position while the driver is not in the driver's seat.
  • (iii) Automatic transmissions incorporating a parking pawl shall have a transmission shifter interlock controlled by the application of the service brake to prohibit accidental engagement of the transmission. All non-park pawl transmissions shall incorporate a park brake interlock that requires the service brake to be applied to allow release of the parking brake.

(bb) TURNING RADIUS.

  • (i) A chassis with a wheelbase of 264 inches or less shall have a right and left turning radius of not more than 42 1/2 feet, curb to curb measurement.
  • (ii) A chassis with a wheelbase of 265 inches or more shall have a right and left turning radius of not more than 44 1/2 feet, curb to curb measurement.

206-2 Wyo. Code R. § 2-5