How many daily hours of sleep does an adult need to maintain alertness? Do you currently have car insurance? Insurance is mandatory to drive in Ohio Yes I have insurance. But please show me your best quotes. No, please help me find the best insurance. Question How many daily hours of sleep does an adult need to maintain alertness? Answers One to two hours Three to four hours Five to six hours Eight to nine hours Explanation Being properly rested is essential to the safe operation of a CMV. To maintain alertness, most people need eight to nine hours of sleep per night.
