According to German law, you are not permitted work more than 10 hours in a row. This does not include a 1-hour break, meaning you can work a total of 11 hours with a one-hour break in one go. You must be given at least 11 hours’ time off between two shifts.
Breaks are not mandatory for shifts under 6 hours. If you work longer than 6 hours, you must take a break lasting at least 30 minutes. This break allowance increases to 1 hour for shifts longer than 9 hours.