> For the complete documentation index, see [llms.txt](https://railnology.gitbook.io/railnology-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://railnology.gitbook.io/railnology-docs/certification-programs-railcert/what-is-a-dsle.md).

# What Is a DSLE?

A Designated Supervisor of Locomotive Engineers (DSLE) is a railroad supervisor authorized under 49 CFR §240.105 to test, evaluate, and certify locomotive engineers.

## To Be Designated as a DSLE

A person must:

* Be a certified locomotive engineer
* Complete a minimum of 2 hours of initial training on Part 240 requirements
* Pass a written examination of at least 25 questions with a score of 90% or higher
* Make at least one qualifying trip over each territory they are responsible for

## Ongoing DSLE Requirements

Once designated, a DSLE must:

* Conduct at least one annual check ride (operational monitoring) per engineer under their supervision
* Complete refresher training every 3 years (minimum 30 minutes)
* Make at least one territory qualification trip per year

Railnology tracks all DSLE requirements automatically and alerts you before deadlines approach.