The CO-SAFE is a field mounted instrument used to monitor the level of Carbon Monoxide in the atmosphere in it’s vicinity. The microcontroller based standalone system can be operated independently, or can also be interfaced to a PLC or DCS through a RS485 communication port on Modbus RTU protocol. The instrument uses a precision two/three-wire Gas Sensor which monitors the levels of Carbon Monoxide continuously and displays the gas level on a large digital read-out while providing audio/visual alarms on a Hooter and Beacon when the set values are exceeded. The Display indicates the CO Gas level in PPM units and may be used to configure the instrument, set the measured Gas range, Alarm Levels, Hysteresis levels, Alarm Types and Alarm Delays. The instrument offers four Relay controls, analog signal retransmission, data communication on a RS485 port on ModbusRTU, Data Logging of the gas levels. A bright and flashing red Beacon and an electronic hooter provide audio-visual alarm feedback with annunciation.