In the workplace, breaks are very important. California’s Industrial Welfare Commission (IWC) has made rules to ensure that employees get the breaks they need. One important rule is that rest periods are not the only times when workers can use the toilet.
According to the IWC Wage Orders, rest periods are separate from toilet breaks. This means that when workers take a rest break, it should be in a suitable place that is different from the toilet area. This rest area should be available during work hours.
If an employee needs to use the toilet during work, it doesn't necessarily count as a rest period. Employers cannot strictly treat a toilet break the same as a rest period. They still must additionally give proper rest breaks. This does not mean that employees can take very long breaks or spend too much time away from their work. Employers can still make reasonable rules about how long breaks can be.
(See Link: https://www.dir.ca.gov/iwc/wageorderindustries.htm)