A Passive Infrared (PIR) sensor for a restroom is a motion detection device commonly used to automate lighting and improve energy efficiency in commercial and residential bathrooms. PIR sensors detect heat emitted by humans and animals, triggering the activation of lighting systems when someone enters the restroom and turning them off after a period of inactivity. In a restroom setting, PIR sensors are typically installed in strategic locations such as near the entrance or within cubicles to ensure coverage of the entire area. When a person enters the restroom, the sensor detects their movement and signals the lighting system to turn on, providing immediate illumination. After a preset time of no detected motion, the sensor automatically switches the lights off to conserve energy. PIR sensors offer several benefits for restroom applications. They enhance convenience by eliminating the need for manual light switches, particularly useful in busy environments where hands-free operation is desirable for hygiene reasons. Moreover, they contribute to energy savings by ensuring lights are only in use when needed, reducing electricity consumption and operational costs over time. Overall, integrating PIR sensors into restroom lighting systems enhances user experience, improves energy efficiency, and supports sustainable building practices in both commercial and residential settings.