I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your situation.
There is unfortunately no California State or Federal law that regulates how many hours an employee may be required to work or that requires days off. However, employers who have employees on call 24 hours per day must compensate employees for that time, and it doesn't sound like the agreement your husband's employer has offered complies with the law.
A non-exempt employee must be paid their regular rate of pay for up to 40 hours worked per week, plus overtime for hours worked in excess of 40. Federal law does allow an exemption for employees whose jobs necessarily require irregular work hours, but I do not believe your husband meets that exception. First, the company could easily schedule him for 8-10 hours per day and schedule someone else for his off hours. He might have some down time, but there's nothing that requires employees to work constantly during their scheduled shifts. But even if you accept that his hours have to be irregular, the exception only allows for employees to work up to 60 hours per week. Take a look at this article:
On call time is considered work time if the employee is not reasonably free to pursue his own activities during that time. So, if he always has to report within 30-45 minutes of getting a call, you could argue that it's not his own time. If he's getting calls regularly seven days a week, if he's never allowed to drink because he might get a call, if calls come so frequently he doesn't have meaningful time to himself, then he needs to be getting paid, essentially, for 24 hours per day. His employer probably doesn't want to pay him for 24 hours a day, and it's possible that once they're aware they're in violation of the law, they'll hire someone else to cover some off hours for him and save them some money.
One option here is to make a complaint with the Department of Labor. It is possible to file an anonymous complaint, but then it'll be more difficult for him to get updates. At the same time, it would be a violation of federal law for them to fire him for reporting the fact that they're underpaying him. He'd be able to sue for reinstatement, back pay, and attorneys' fees.
The only way to get guaranteed time off is to quit. But he may be able put pressure on his employer to hire other employees in order to ensure compliance with minimum wage and overtime requirements. It could help to have a local attorney send them a letter if you'd prefer to work things out without involving the state.
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