When not in use, a cell phone must be:

The requirement for a cell phone to be turned off and stowed out of sight when not in use emphasizes safety and compliance with regulations, particularly in settings such as workplaces or when operating heavy machinery. This ensures that there are no distractions that could compromise attention and safety. Turning off the phone eliminates any possibility of it ringing or vibrating, which can divert focus from critical tasks. Stowing it out of sight reinforces this by removing the visual temptation to check the phone, fostering a more attentive and secure environment. Other options might not provide the same level of assurance that the device won't interfere with activities or safety protocols, as simply keeping it in a pocket, on silent mode, or in a backpack can still lead to distractions.