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Air Quality in Indiana

Air Quality in Indiana > DieselWise > Public and School Transportation  > STAI School Bus Idling Policy Resolution STAI School Bus Idling Policy Resolution

Whereas school buses transporting students to and from school are powered by diesel engines;

Whereas the U.S. Environmental Protection Agency has found that exposure to diesel exhaust, even at low levels, is likely to pose a risk of lung cancer as well as other respiratory risks;

Whereas diesel emissions are well documented as an asthma trigger;

Whereas diesel emissions contribute to noncompliance of various federal health-based air quality standards;

Whereas air quality inside the school building is affected by air quality outside the school building;

Whereas diesel emissions frequently pervade portions of the school buildings when school buses are idling adjacent to the school;

Now therefore, be it resolved, that the Student Transportation Association of Indiana recommends the adoption of the voluntary idling policy relating to school buses.

Section 1: Bus Warm-up
  • At 32 degrees or above, buses will be allowed to idle for up to five (5) minutes;
  • From 20 degrees to 32 degrees buses will be allowed to idle for up to fifteen (15) minutes;
  • From 20 degrees and below, buses will be allowed to idle for up to thirty (30) minutes; or until front windows are defrosted and all safety equipment is operable.
Section 2: Loading/Unloading at Schools

All buses arriving at schools to load or unload students who are going to remain at the school longer than three (3) minutes will turn off their engines after the appropriate cool-down time and leave them off until the buses are ready to depart. This section also applies to field trips and arrival and departure from those locations.

Section 3: Auxiliary Equipment/Extreme Temperatures

When extreme temperatures require the idling of the bus to maintain a reasonable level of comfort inside the bus, the above sections may not apply. This section also applies to auxiliary equipment (i.e. lift equipment for loading and unloading students with disabilities.) However, the limiting of extended idling times is still encouraged.