In Germany it's dependent on the work hours and type of physical activity, for me it's:
<6 hours, no break (for adults)
6-8 hours, 30 minutes break
8-10 hours, 45 minutes break
>10 hours, 1 hour
6-9 hours, 30 minutes
>9 hours, 45 minutes

With breaks being a minimum of 15 minutes at a time, and you're not allowed to work workout breaks for more than 6 hours at a time.
if you have a job where you have to concentrate a lot (assembly lines, bus/truck drivers, air traffic controllers) these times change a lot, sometimes down to like 1 hour maximum continuous work and then 15-30 minutes of break time.

EDIT: @zaphod@sopuli.xyz was right, Source (in German)