Evaluation of Different Carbon Monoxide Sensors for Battery Charging Stations.

Hydrogen (H) gas released during battery charging can result in cross-interference for carbon monoxide (CO) sensors used for early fire detection and compromise the integrity of the mine atmospheric monitoring system (AMS). In this study, a series of laboratory-scale and full-scale experiments were conducted to evaluate the responses of different CO sensors to H gas. In the laboratory-scale experiments, constant H concentrations in the airflow, from 100 to 500 ppm, pass through sensors. While in the full-scale experiments, increasing H concentrations generated as a byproduct from charging the batteries at the battery charging station rise to the sensors under different ventilation scenarios. The H concentrations at the CO sensor location were measured using H sensors and were correlated with the CO sensor response. The effects of ventilation and sensor location on the CO sensors responses were also analyzed. The results of this study can help mining companies to select appropriate CO sensors and improve the deployment of these sensors to ensure the safeguard of underground miners.