Why do railroads allow locomotives to idle?
During normal railroad operations, locomotives sometimes must wait for freight cars to be switched and/or picked up, for another train to clear track on which the locomotive is to proceed, or for mechanical service. Historically, locomotives have been left idling while they are waiting. In some cases, there are practical or safety reasons why locomotives need to be left idling. In other cases, locomotive operators might simply idle the engines due to custom, habit, or misunderstandings about diesel engines. As we describe in this fact sheet, EPA is working to address all of these causes. The reasons why current locomotives may need to be left idling can be technological or related to worker and passenger needs. First, diesel engines can be difficult to start in extremely cold temperatures, especially larger diesel engines such as those used in locomotives. Also, locomotive engines are typically designed to use water without antifreeze because water is more efficient at cooling the engi
