Should it be "on your job" or "during your job"?

Question

I am not sure if we should say "during your job" or "on your job" if you're doing X as part of your job and not as a side thing or kill time.

For example:

The sketch artist draw portraits on the job after hearing a description of the suspects.

Answer 1

Common usage is one of

A sketch artist’s job is drawing portraits based on a verbal description of a suspect.

or

The sketch artists draw portraits on the job …

or

The sketch artists draw portraits at work …

The definite article reads a bit strangely if you are describing the profession as a whole, in which case

Sketch artists draw portraits at work …

would be better. Where the definite article might make sense is if you are referring to a group of sketch artists who are part of a specific larger team.

To emphasize the purpose for which someone is employed, in contrast to responding to email, filing paperwork, attending staff meetings, and other overhead or unproductive tasks, use

Sketch artists get paid to draw …

Slightly more formal is

The job description for sketch artists includes drawing …

or

A sketch artist’s primary job function (or primary duty) is drawing portraits …