California labor law has specific provisions related to the number of days an employee is permitted to work before a rest day is required. These regulations are set forth in the California Labor Code -- specifically in sections 551-556 -- and apply equally to public agencies, cities and counties as well as private employers.
California Labor Code
Section 551 of the California Labor Code provides that "every person employed" in "any occupation" is entitled to one day of rest in every seven days, and Section 552 further clarifies that no employer is permitted to require employees to work in excess of six days out of a seven-day period. Violation of these provisions of the Labor Code is a misdemeanor (Section 553).
Although the Labor Code is strict on the need for one day of rest in seven, Section 554 does provide employers with some flexibility in how to administer the days of rest. This section of the code clarifies that employees must not necessarily take a day off in a seven day period, as long as the rest days are provided for during the same calendar month. For example, if an employer "reasonably requires" the employee to work for 21 consecutive days in a row, this is permissible as long as the employer subsequently provides for the three missed days of rest at some point during the month.
Some narrowly limited exemptions are specifically mentioned in Section 554 of the California Labor Code. These exemptions are related to occupational fields -- specifically, employees working in agriculture or with trains -- in an emergency, or in cases where the employee is acting to protect "life or property from loss or destruction." As is common with other provisions of the Labor Code, employers are permitted to enter into a collective bargaining agreement that expressly differs from the code. The Department of Labor Standards Enforcement also has broad jurisdiction to exempt employers and employees from the regulations in cases where "hardship will result."
The regulations do not apply to part-time employees who work less than 30 hours a week, or six hours a day. It is not recommended to assume a blanket exemption from the policy for part time workers, however. The code specifically states that the exemption only applies when the "total hours of employment" are less than 30 in a week. Therefore if an employee works overtime -- taking him above the 30-hour threshold -- he would likely be eligible for a rest day according to the code. Employers should assess compliance with the code according to hours worked and not the full- or part-time designation of the employee.