Electronic Nose Calibration Process for Monitoring Atmospheric Hazards in Confined Space Applications

Confined space is an enclosed area with limited space to perform work activity which could contribute towards atmospheric hazards accidents. The atmospheric air sample can be monitored using the integration of electronic nose (e-nose) together with mobile robot. In this work, we reported the calibration of e-nose which consists of three individual Metal Oxides Semi-Conductor (MOS) gas sensors together with oxygen, temperature and humidity sensors for environmental monitoring. The sample gas is using two different gas cylinders. Gas cylinder 1 contains of hydrogen sulphide (H2S), carbon monoxide (CO) and methane (CH4) while gas cylinder 2 contains air with zero grades. The analogue to digital converter (ADC) readings from the MOS gas sensors response is converted into parts per million (ppm) and percentage (%) readings. The concentrations of gas in cylinders were validated using commercial gas detector. The difference readings between the MOS gas sensors in e-nose and commercial gas detector to the gas cylinder 1 is calculated as calibrated value. The gas cylinder 2 exposed is to identify the ability of MOS gas sensors to back in baseline level. Results proved the ability of the developed e-nose to be use in environmental gas detections and monitoring.