Ill. Admin. Code tit. 92, § 435.APPENDIX E
a) GRAB HANDLES
1) Exterior
Not required.
2) Interior
Stainless steel clad, solidly attached on the left side of the entranceway as a person enters the bus, and as long as practicable. An optional grab handle can also be located on the right side of the entranceway.
b) HEATERS
A) a hot water and/or combustion type heater; or
An interior temperature of not less than 10° Celsius (50° F) shall be maintained throughout the bus while the bus is moving at 75 kilometers per hour (46.6 miles per hour) in calm air at the average minimum January temperature, as established by the Weather Bureau, U.S. Department of Commerce, for the area in which the bus is to be operated.
Each heater shall bear a nameplate that shall identify the heater manufacturer and state the heater capacity rating when tested as recommended in SAE Recommended Practice J638 (November 1998), or when tested in accordance with other nationally recognized standard or code. The recommended practice, standard, or code under which the heater is rated shall be identified on the nameplate. The nameplate shall constitute certification by the heater manufacturer that the heater performance is as shown on the plate.
Heater hoses shall be supported so as to prevent wear due to vibration. The hoses shall not dangle or rub against the chassis or sharp edges and shall neither interfere with nor restrict the operation of any engine function (such as an emission or ignition control mechanism). Heater hoses shall be protected or baffled between the point at which they enter the passenger compartment and the point of attachment to the heater so that, in the event of hose rupture or disconnection, passengers and/or driver will not be subject to hot water burns.
Auxiliary fuel-fired heating systems are permitted, provided they comply with the following:
c) HORN
At least one horn shall be provided giving an audible warning at a distance of 200 feet and shall be conveniently controlled from the operator's seated position. (See Section 12-601 of the Illinois Vehicle Equipment Law.)
Optional exterior air horn is permitted.
d) INSTRUMENTS AND INSTRUMENT PANEL
Shall be equipped with 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. An indicator light instead of a pressure or temperature gauge is permissible.
e) INSULATION
The ceiling and sidewalls shall be thermally insulated with a fire-resistant material that shall reduce the noise level and vibrations.