Can visible notification appliances designed for wall mounting be mounted on the ceiling?

Visible notification appliances designed for wall mounting should not be mounted on the ceiling because their specifications and effectiveness are typically based on their intended use on vertical surfaces. These appliances are engineered to emit light patterns and intensities that optimize visibility from specific angles, typically when mounted on a wall. Mounting them on the ceiling can lead to reduced effectiveness in alerting occupants, as the light may not be directed towards the intended areas where people might be located, potentially compromising safety during an emergency.

Additionally, various building codes and standards, such as those outlined in the National Fire Alarm and Signaling Code (NFPA 72), provide regulations regarding the installation of notification appliances. These codes emphasize the necessity of following manufacturer instructions and specific guidelines for wall-mounted devices to ensure proper functioning and visibility in emergency situations.