Current through Register Vol. 35, No. 18, September 24, 2024
A.
AIR CLEANER
(1) The engine
intake air cleaner system shall be furnished and properly installed by the
chassis manufacturer to meet engine manufacturer's specifications.
(2) All diesel engine air filters shall
include a restriction indicator of the latching type that retains the maximum
restriction developed during operation of the engine. The indicator should
include a reset control so the indication can be returned to zero when
desired.
B.
ALTERNATIVE FUELS
(1) Chassis shall
meet all BUS CHASSIS STANDARDS.
(2)
Chassis shall meet all applicable 49 CFR 571 federal motor vehicle safety
standards (FMVSS).
C.
AXLES: The front and rear ends, including suspension assemblies,
shall have a gross axle weight rating at ground at least equal to that portion
of the load as would be imposed by the chassis manufacturer's maximum gross
vehicle weight rating.
D.
BRAKES
(1) The braking system shall
include the service brake and a parking emergency brake.
(2) Buses using air in the operation of the
brake system shall be equipped with warning signals, readily audible and
visible to the driver, that will give a continuous warning when the air
pressure available in the system for braking is 60 psi (pounds per square inch)
or less. An illuminated gauge shall be provided that will indicate to the
driver the air pressure in pounds per square inch for the operation of the
brakes.
(3) Any brake system with a
dry reservoir shall be equipped with a check-valve or equivalent device to
ensure that in the event of failure or leakage in its connection to the source
of compressed air, the stored dry air shall not be depleted by the leakage or
failure.
(4) Buses using a
hydraulic-assist brake 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 primary source and in the event of
discontinuity in that portion of the vehicle electrical system that supplies
power to the backup system.
(5) The
brake lines and booster-assist lines shall be protected from excessive heat and
vibration and installed in a manner, which prevents chafing.
(6) All brake systems shall be designed to
permit visual inspection of brake lining wear without removal of any chassis
components.
(7) All type C and type
D school buses shall be equipped with air brakes.
E.
BUMPER, FRONT
(1) All school buses shall be equipped with a
front bumper. The front bumper shall be furnished by the chassis manufacturer
as part of the chassis on all types of chassis unless there is a specific
arrangement between the chassis manufacturer and body manufacturer that the
body manufacturer will furnish the front bumper.
(2) Unless energy absorbing bumper is used,
the front bumper shall be of pressed steel channel or equivalent material at
least 3/16-inch thick and not less than 8-inch 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.
(3) 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.
(4) If tow eyes or hooks are
furnished they shall be attached so as not to project beyond the front bumper.
Tow eyes or hooks attached to the frame chassis may be furnished
by the chassis manufacturer. This installation shall be in accordance with the
chassis manufacturer's standards.
(5) 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.
(6) The exhaust system on vehicles equipped
with a power lift unit may be routed to the left of the right frame rail to
allow for the installation of a power lift unit on the right side of the
vehicle.
F.
CLUTCH
(1) Clutch torque capacity shall
be equal to or greater than the engine torque output.
(2) A starter interlock shall be installed to
prevent actuation of the starter if the clutch is not depressed.
G.
COLOR
(1) Chassis, including wheels and 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. Activity school buses may be team
colors.
(2) Demountable rims, if
used, may be, silver, gray or black as received from the wheel manufacturer.
Wheels may be polished aluminum, chrome or of a team color on activity buses
only.
H.
COOLING
SYSTEMS (ENGINE): Engine cooling system shall be sufficient capacity to
properly maintain engine-operating temperature to manufactures specifications
at the rated horsepower.
I.
DRIVE SHAFT: Drive shafts shall be protected by a metal guard or guards
around the circumference of the drive shafts to reduce the possibility of its
whipping through the floor or dropping to the ground if broken.
J.
ELECTRICAL SYSTEM
(1)
Battery
(a) Storage battery shall have minimum cold
cranking capacity rating equal to the cranking current required for 30 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
optional equipment and local environmental conditions.
(b) Since all batteries are to be secured in
a sliding tray in the body, chassis manufacturers shall temporarily mount the
battery on the chassis frame, except that van conversion or cutaway
front-section chassis may be manufacturer's standard configuration. In these
cases, the final location of the battery and the appropriate cable lengths
shall be according to the design objectives, or as mutually agreed upon by the
chassis and body manufacturer. In all cases, however, the battery cable
provided with the chassis shall have sufficient length to allow some slack.
Battery storage area shall be secured with a locking system or release system
that shall be accessible from the driver's compartment.
(2)
Alternator
(a) All type A-II buses up to 15,000 lbs.
GVWR shall have a minimum 60-ampere alternator.
(b) Types A-II buses over 15,000 lbs. GVWR
and all types C and D buses shall be equipped with a heavy-duty truck or
bus-type alternator, having a minimum output rating of 130 amperes. Alternators
of 130 through 145-ampere design shall produce a minimum of 50 percent amperes
output at engine idle speed.
(c)
All buses equipped with an electrical power lift shall have a minimum
130-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.
(3)
Wiring
(a) All wiring shall conform to current
applicable recommended practices of the society of automotive engineers (SAE).
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 130 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 (rheostat
controlled by headlamp switch)
(4)
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 must be wired separately
from the body-controlled solenoid.
(5)
Daytime running light
(a) Exterior low-beam headlights and
taillights may be provided with a switch to automatically operate said lamps
when the vehicle's ignition is engaged. This switch, if furnished, shall not
engage while the starter is engaged. If this switch designed to provide reduced
illumination under normal operating conditions, a means whereby the headlights
and taillights can be engaged at full power shall be provided.
(b) Chassis manufacturer shall provide a
means for body manufacturer to include the taillights in the daytime running
light (DRL) circuit.
K.
ENGINE FIRE EXTINGUISHER (optional
equipment): Manufacturer may provide an automatic fire extinguisher
system in the engine compartment.
L.
EXHAUST SYSTEM
(1) 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.
(2) Tailpipe shall be constructed of a
corrosion-resistant tubing material at least equal in strength and durability
to 16-gauge steel tubing.
(3)
Chassis manufacturers shall furnish an exhaust system with tailpipe of
sufficient length to exit the rear of the bus at the left side of the bus body
no more than 18-inches 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 types C and D vehicles,
the tailpipe shall not exit beneath a fuel fill or emergency door
exit.
(b) Type A chassis may be
furnished with the manufacturer's standard tailpipe configuration.
(4) Exhaust system on a chassis
shall be properly insulated from the fuel tank connections by securely attached
metal shield at any point where it is 12-inches or less from tank or tank
connection.
(5) Muffler shall be
constructed of corrosion-resistant material.
(6) The exhaust system on vehicles equipped
with a power lift unit may be routed to the left of the right frame rail to
allow for the installation of a power lift unit on the right side of the
vehicle.
M.
FENDERS, FRONT-TYPE C VEHICLES
(1)
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.
(2) Front fenders shall
be properly braced and free from any body attachments.
N.
FRAME
(1) 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.
(2) Any secondary
manufacturer that modifies the original chassis frame shall guarantee the
performance of workmanship and materials resulting from such
modification.
(3) Frames shall not
be modified for the purpose of extending the wheelbase.
(4) 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.
(5) Frame lengths shall be provided in
accordance with design objectives, except where body and chassis manufacturer
are the same or have established mutual design criteria for the
vehicle.
O.
FUEL
TANK
(1) Fuel tank or tanks having a
minimum 30-gallon capacity with a 25-gallon actual draw shall be provided by
the chassis manufacturer. The 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. Vehicles with a wheel base of 193-inches and
larger shall be equipped with fuel tank or tanks of minimum 60-gallon capacity
with a 50-gallon actual draw.
(2)
No portion of the fuel system, which 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.
(3) Fuel filter with
replaceable element shall be installed between the fuel tank and
engine.
(4) Fuel tank installation
shall be in accordance with design objectives and all federal motor vehicle
safety standards in effect on the date of manufacture of the bus. 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.
(5) The actual draw capacity of each fuel
tank shall be 83% of the tank capacity.
(6) 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 design objectives.
(7) 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. Installation of LPG tanks shall
comply with national fire protection association (NFPA) 58.
P.
HEATING SYSTEM:
The chassis engine shall have plugged openings for the purpose of supplying hot
water for 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. (School Transportation Manufacturing
Technical Committee Standard No. 001 - Standard Code for Testing and Rating
Automotive Bus Hot Water Heating and Ventilating Equipment.)
Q.
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.
R.
INSTRUMENTS AND INSTRUMENT
PANEL
(1) Chassis shall be equipped
with the following instruments and gauges. (lights in lieu of gauges are not
acceptable, except as noted):
(a)
speedometer;
(b) odometer which
will give accrued mileage (to seven digits), including tenths of
miles;
(c) voltmeter; ammeter with
graduated charge and discharge, with ammeter and its wiring compatible with
generating capacities, is permitted in lieu of voltmeter;
(d) oil pressure gauge;
(e) water temperature gauge;
(f) fuel gauge;
(g) upper beam headlight indicator
light;
(h) brake indicator gauge
light indicator in lieu of gauge is permitted on vehicle equipped with
hydraulic-over-hydraulic brake system;
(i) turn signal indicator light;
(j) start indicator light where
appropriate.
(2) All
instruments shall be easily accessible for maintenance and repair.
(3) 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.
(4) Instrument panel shall have lamps of
sufficient candlepower to illuminate all instruments and gauges and shift
selector indicator for automatic transmission.
(5)
Multi-function gauge (MFG)
(a) The driver must be able to manually
select any displayable function of the gauge on a MFG whenever
desired.
(b) Whenever an
out-of-limits conditions occurs, which would be displayed on one or more
functions of a MFG, then the MFG controller should automatically display this
condition on the instrument cluster. This should be in the form of an
illuminated tell-tale warning light as well as having the MFG automatically
display the out-of-limits indications. Should two or more functions displayed
on the MFG go out-of-limits simultaneously, then the MFG should automatically
sequence between those functions continuously until the condition(s) is
corrected.
(c) The use of a MFG
does not relieve the requirements for audible warning devices, where
required.
S.
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. The oil filter shall have a capacity of at least one (1)
quart.
T.
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.
U.
PASSENGER
LOAD
(1) 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.
(a)
For purposes of calculation, the driver's weight is 150 pounds.
(b) For purposes of calculation, the pupil
weight is 120 pounds per pupil.
(2) 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 GVWR.
(3) Manufacturer's (GVWR) shall be furnished
in duplicate (unless more are requested) by manufacturers to the state agency
having pupil transportation jurisdiction. The state agency shall, in turn,
transmit such ratings to other state agencies responsible for development or
enforcement of state standards for school buses.
V.
POWER AND GRADE ABILITY:
Shall not exceed the manufacturer's recommended standards for the vehicle size.
A maximum speed limiter shall be set at 75 miles per hour. A lower setting is
permissible at the request of the school bus owner. A cruise control mechanism
may be installed on school activity buses only.
W.
RETARDER SYSTEM (OPTIONAL
EQUIPMENT): 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.
X.
SHOCK
ABSORBERS: The bus shall be equipped with double-action shock absorbers
compatible with manufacturer's rated axle capacity at each wheel
location.
Y.
STEERING
GEAR
(1) 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.
(2) If external adjustments
are required, steering mechanism shall be accessible to accomplish
same.
(3) No changes shall be made
in the steering apparatus, which are not approved by the chassis
manufacturer.
(4) There shall be a
clearance of at least 2-inches between the steering wheel and cowl, instrument
panel, windshield, or any other surface.
(5) Power steering is required and shall be
of the integral type with integral valves.
(6) The steering system shall be designed to
provide a means for lubrication of all wear-points, if wear-points are not
permanently lubricated.
Z.
SUSPENSION SYSTEM: A soft
ride suspension system, (taper leaf) low friction parabolic springs, vari-rate
and two stage steel leaf rear springs shall be provided on type C and D buses
where lift equipment is required.
(1) The
capacity of springs or suspension assemblies shall be commensurate with chassis
manufacturer's GVWR rating.
(2)
Leaf rear springs shall be a progressive rate or multi-stage design. Front leaf
springs shall have a stationary eye at one end and shall be protected by
wrapped leaf in addition to the main leaf.
AA.
THROTTLE: The force
required to operate the throttle shall not exceed 16 pounds throughout the full
range of accelerator pedal travel.
BB.
TIRES AND RIMS
(1) Tires and rims 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 and/or tube-type
tires shall not be permitted on any school bus ordered after the effective date
of these standards. Rims on activity buses may be chrome or of a team
color.
(2) Dual rear tires shall be
provided on type A-II, type C, and type D school buses.
(3) 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
49
CFR
571.120(FMVSS).
(4) If the vehicle is equipped with a spare
tire and rim assembly, it shall be the same size as those mounted on the
vehicle.
(5) If a tire carrier is
required, it shall be suitably mounted in an accessible location outside the
passenger compartment. Exception: On type A vehicles, spare tire and carrier
may be mounted behind the last seat at the rear of the bus if adequately
secured and mounted in such a way as not to interfere with the emergency
exit.
CC.
TRANSMISSION
(1) 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.
(2) In manual
transmissions, second gear and higher shall be synchronized except when
incompatible with engine power. A minimum of three forward speeds and one
reverse speed shall be provided.
(3) 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.
(4) A two-speed axle
is not permitted.
DD.
TURNING RADIUS
(1) 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.
(2) 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.
EE.
UNDERCOATING: The chassis
manufacturers or their agent shall coat the undersides of steel or
metallic-constructed front fenders with a rust-proofing compound for which
compound manufacturers have issued notarized certification of compliance to
chassis builder that the compound meets or exceeds all performance and
qualitative requirements using modified tests.
FF.
VEHICLE INTERLOCK SYSTEM:
School buses equipped with a power lift shall meet
49 CFR
571.403 and
571.404(FMVSS).
