### Question
What is the definition of long-duration idling?


### Answer
The definition of **long-duration idling** is as follows in *42 U.S.C. § 16104*:

> the operation of a main drive engine or auxiliary refrigeration engine, for a period greater than 15 consecutive minutes, at a time at which the main drive engine is not engaged in gear

#### Citation:
  - *42 U.S.C. § 16104*
  - Heading: **CHAPTER 149-NATIONAL ENERGY POLICY AND PROGRAMS > SUBCHAPTER VII-VEHICLES AND FUELS > Part D-Miscellaneous**

