Affordable Analog OxygenMonitor forMaintaining Safe Oxygen Concentration in IndustrialEnvironments

Abstract

As industrial fields become more intertwined and complex, there is an increasing demand for a suitable & reliable method of monitoring the concentration of Oxygen in the surrounding work environment. It is often required that these Oxygen levels retain consistent values in order to protect the workforce and the material in use. This paper proposes an analog system which uses a combination of operational amplifiers in different configurations. They have been designed to convert the current signals generated by an Electrochemical sensor and compare these signals to a reference voltage set by the user. Features of the system include long battery life, affordability compared to other monitors on the market, analog signal precision and a wide variety of preset configurations and calibration methods to use in confined spaces. Multiple tests were performed using the device to monitor the concentration of Oxygen outdoors. The device’s output is measured in volts using a voltmeter and converted to a concentration of Oxygen detected according to the formulas derived for the system. The results were then compared to the weather and humidity forecast data provided by internet sources and research done on the relationship between humidity and the concentration of Oxygen. This helped in fine tuning the circuit, fix previous issues with the prototype and implement more features. The system proposed was presented to and certified by Oman Chromite Company (SAOG) for use in their opencast and underground mines.