The ability to take bathroom breaks should not be considered a privilege. Denying workers their rights to use the bathroom facilities as needed could be to the detriment of a worker's health. Denying workers the ability to use the restroom when they need to, or with unfair delays or obstacles, is a violation of workers' rights and an affront to dignity.
There is not a federal law that specifically applies to the number and duration of bathroom breaks. However, there are Occupational Safety and Health Administration (OSHA) regulations which require employers to provide adequate bathroom facilities, and prevent employers from imposing unreasonable restrictions on bathroom use. The intent of these regulations is that employees are able to use bathroom facilities promptly, recognizing that the frequency of bathroom visits necessary may vary among employees, depending on factors such as the temperature, medical conditions and the effects of medication, and fluid intake.
In production environments where the absence of one or more individuals can adversely affect a productive work flow, OSHA recommends the adoption of a signal system, so that employees can request relief by signaling for another employee to take the spot on the work station. If employees are not being forced to wait an unreasonable amount of time for bathroom use, a system like this complies with OSHA regulations.