According to the FDA, what is the maximum time that sunlamps radiating UV rays can operate before automatically shutting off?

The correct context here involves understanding the regulations established by the FDA regarding sunlamp usage in relation to the safety of consumers. The FDA mandates that sunlamps must have an automatic shut-off feature that activates after a maximum duration of 15 minutes of operation. This regulation is designed to minimize the risk of overexposure to ultraviolet (UV) radiation, which can lead to severe skin damage and increase the risk of skin cancer.

The interval of 15 minutes is significant because it reflects a balance between allowing sufficient exposure for tanning while also safeguarding public health by preventing prolonged exposure that could lead to harmful effects. Given this standard, the correct choice indicates that none of the provided options accurately reflects this requirement, as none offer a maximum time of 15 minutes or less for operation before automatic shut-off. Thus, "None of the above" is the appropriate answer in the context of the FDA’s guidelines.