Use the ZFR1821 or ZFR1822 ZFR Pro Wireless Field Bus Routers only to provide an input to equipment under normal operating conditions. Where failure or malfunction of a ZFR Pro Router or loss of communications due to wireless interference could lead to personal injury or property damage to the controlled equipment or other property, additional precautions must be designed into the control system. Incorporate and maintain other devices, such as supervisory or alarm systems or safety or limit controls, intended to warn of or protect against failure or malfunction of a ZFR Pro Router.