Except for mirrors, which may project 152 mm (6 inches), a
school bus shall not exceed 2.625 m (8 feet) in width, 4.429 m (13 feet 6
inches) in height, nor 13.78 m (42 feet) in length (Sections 15-102 and 15-107
of the Code). Exceptions to the above are shown in Section
440.420 of this Part. Various
portions of the bus chassis shall conform to the requirements set forth under
the following subsections.
a) Air
Cleaner.
1) A dry element type air cleaner
shall be provided.
2) All diesel
engine air filters shall include a latch-type restriction indicator that
retains the maximum restriction developed during operation of the engine. The
indicator should include a reset control so the indicator can be returned to
zero when desired. Diesel-powered school buses that meet the definition of a
Type I-A school bus, as defined in Section
440.220, are exempt from the
restriction indicator requirement.
b) Axles. Must meet federal chassis
requirements as indicated on the federal certification label as required by
49
CFR 567 and
49 CFR 568.
d) Brakes. See the FMVSS
for requirements (49 CFR
571.105).
e) Bumper, Front. The front bumper shall be
of channel type cross section, shall be formed from rolled steel at least 4.5
mm (.177 inches) thick, shall have not less than a 200 mm (7.9 inches) vertical
face, and shall extend to protect the outer edges of the fenders, or the body
of a forward control bus. The bumper shall be of sufficient strength to permit
pushing another vehicle of equal gross weight without permanent distortion.
Exception: For school buses that meet the definition of a Type I-A school bus,
as defined in Section
440.220, the bumper may meet
manufacturer's specifications when the Type I-A school bus is equipped with a
driver side air bag.
f) Clutch. A
bus having a manual shift transmission shall be equipped with the type and size
of clutch recommended by the incomplete vehicle manufacturer for heavy duty
service between the engine and transmission installed in the bus.
g) Color and Paint. See Section
440.420(i) of
this Part.
h) Drive Shaft. A
suitable guard shall be provided for each segment of the drive shaft to prevent
accident or injury if the shaft breaks or becomes disconnected.
i) Engine. Type and displacement may be
specified by the purchaser.
j)
Exhaust System.
1) The exhaust pipe, muffler
and tail pipe shall be outside the bus body and attached to the chassis.
AGENCY NOTE: As mandated by the United States Environmental
Protection Agency (USEPA), diesel-powered engines manufactured after December
31, 2006 are required to meet stricter standards that will reduce emissions of
particulate matter and nitrogen oxides into the atmosphere. School bus
manufacturers may be required to modify exhaust systems to meet the USEPA
requirements, e.g., mufflers may be replaced with after-treatment devices that
significantly reduce toxins released into the atmosphere. Modifications to
exhaust systems made in compliance with the USEPA requirements are acceptable
provided they do not impact the safe operation of the school bus.
2) The exhaust system shall be
insulated from any insulated wire, flammable material, brake hose or line, or
fuel system component by a securely attached metal shield at any point where
the exhaust system is 11.8 inches (300 mm) or less (four inches (101.6 mm) or
less if diesel powered engine) from the components listed in this subsection
(j)(2).
3) The tail pipe shall be
extended to exit the exhaust gases either to the right or left side, or rear of
the bus, except for prohibited zones as shown in Illustration C of this
Part.
4) The tail pipe shall extend
out to but not more than 1 inch (25.4 mm) beyond the perimeter of the body or
the bumper.
5) The shielding of
engine compartment components shall be governed by the chassis manufacturer's
standards.
6) Each gas conducting
component that is not of stainless steel shall be of commercial heat and
corrosion resistant exhaust system material and shall be nonflexible.
7) For school buses that meet the definition
of a Type I-A school bus, as defined in Section
440.220, the tail pipe may meet
the chassis manufacturer's standard configuration. However, the tail pipe shall
not exit beneath any fuel filler location or beneath any emergency exit
door.
l) Generating System.
The generating system may utilize either mechanical rectification (commutator
type) or diode rectification (alternator type).
1) The generator output shall be regulated
automatically so as to provide for efficient battery charging without causing
damaging potentials or currents in any part of the electrical system. Automatic
means shall be provided to prevent battery discharge through the generator
while the generator is not delivering current.
2) The generator in a nominal 12 volt system
shall be able to deliver a continuous current of 60 amperes, or more, while its
automatic regulating devices are connected and functioning properly and the
engine is running no faster than the speed at which it delivers its maximum net
torque at the engine flywheel.
3)
The generator in a nominal 12 volt system shall be able to deliver a continuous
current of 20 amperes, or more, while its automatic regulating devices are
connected and functioning properly and the engine is running no faster than the
curb idle speed recommended by the engine manufacturer.
4) The generator in a nominal voltage system
higher or lower than 12 volts shall be able to deliver at least the same
continuous power (watts) as indicated under subsections (l)(2) and(3) of this
Section, at the engine speeds indicated therein.
AGENCY NOTE: Where a bus must operate under adverse
conditions such as low engine speeds, frequent periods of engine idle, and/or
with high electrical load (frequent use of signals and interior lamps, high
heater/defroster loads, etc.) for prolonged periods of time, the purchaser
should specify a larger generator commensurate with operating
conditions.
m)
Horns.
1) At least one horn shall be
installed giving an audible warning at a distance of 200 feet. The horns shall
be controlled conveniently by the seated driver and tested in accordance with
SAE Standard J377 (March 2001).
2)
A siren, whistle, or bell may not be installed to attract attention of
pedestrians or drivers outside the bus (Section 12-601(b) of the Code). This
prohibition shall not be interpreted to prohibit use of such devices inside the
bus body to provide warnings to the bus driver.
n) Instruments. The bus shall be equipped
with at least the following nonglare illuminated instruments and gauges mounted
for easy maintenance and repair and in such a manner that each is clearly
visible to the seated driver:
1) Ampere meter
or volt meter, with "charge" and "discharge" indications, provisions for 100
ampere, or more, continuous current indication, and arranged so as to remain
unharmed by any ampere meter current flow resulting from the installed
generator operating at its maximum output;
2) Gauge, Air Pressure or Vacuum (where air
pressure or vacuum is utilized either to apply or to assist in applying the
service brakes);
3) Gauge, Engine
Coolant Temperature;
4) Gauge,
Engine Oil Pressure;
5) Gauge,
Fuel;
6) Odometer (may be combined
with speedometer; may indicate kilometers traveled if such indication is shown,
clearly and conspicuously);
7)
Speedometer, with both miles per hour and kilometers per hour scales that are
easily readable.
o)
Lamps and Signals. See Section
440.420(u) of
this Part.
p) Oil Filter. A "full
flow" type engine oil filter of approximately 1 liter (1 quart) capacity shall
be installed. The purchaser may specify additional "full flow" or "by-pass"
type filters, or oil treatment devices.
q) Shock Absorbers. Two front and two rear
double-acting shock absorbers of adequate capacity shall be
installed.
r) Spare Tire
(Optional). The spare tire and rim, if supplied, shall be of the same size
designation and load rating as the largest tire and rim installed on the bus.
Each spare tire and rim shall be suitably mounted in an accessible location
outside the passenger compartment.
s) Springs and Suspension. Each spring and
other component in any of the suspension systems shall be capable of supporting
its share of the rated gross axle weight during normal operations. Where spring
failure could result in total loss of control of the bus, suitable means shall
be provided to make such total loss most unlikely.
t) Steering Mechanism. Power steering is
optional. The steering mechanisms shall provide safe and accurate performance
at maximum load and speed and shall be adjustable while installed on the
completed bus. After the date of manufacture of the incomplete vehicle, the
steering mechanisms shall not be modified unless such modification is done with
the concurrence of the incomplete vehicle manufacturer and in accordance with
the incomplete vehicle manufacturer's instructions.
u) Tow Hooks, Front (Optional). A front tow
hook may not extend beyond the front of the front bumper. Each front tow hook
not fastened securely to the chassis frame shall be connected to the frame by
suitable braces.
v) Transmission.
Unless otherwise specified by the purchaser, the transmission shall be
manual-shift.
1) A manual-shift transmission
shall provide not less than 4 forward gear ratios and 1 reverse gear ratio. A
synchromesh shifting mechanism shall be provided for each forward gear ratio
except for the highest ratio; i.e., "first gear" or "low gear". (Synchromesh
may be specified for "first" or "reverse" gears at the purchaser's
option.)
2) An automatic
transmission may be specified by the purchaser. Such transmission shall provide
not less than 3 forward gear ratios and 1 reverse gear ratio.
w) Undercoating. The entire
underside of front fenders or wheel wells shall be coated with a fire-resistant
undercoating material in order to seal joints and to reduce corrosion and
noise. Nonmetallic components need not be coated.