Idle-LokTM is designed to limit the idling times of non-working equipment. It can be set up to turn OFF the engine or sound an alarm/beeper. On a school bus, it does not shut off the engine (for safety reasons) and instead honks the OEM horn to alert the driver and others that the bus has idled beyond a set time period.
A Win - Win Situation
It is documented that limiting idling times reduces fuel consumption. Naturally, if the engine is running less, we are generating less air pollution.