Development of A Measurement System for Volcanic CO and CO2 Concentrations

Volcanic activity is a natural source of CO (carbon monoxide) and CO
₂
(carbon dioxide), two powerful pollutant gases which have harmful effects on human health and the environment. The high concentration of CO and CO
₂
has a potential risk to surrounding residents, especially in the source area. Malang, East Java, Indonesia, is a city that is surrounded by three volcanoes. The volcanoes produce CO and CO
₂
in a significantly high concentration. This condition triggers the need for a reliable measurement system. Based on the needs, this study aims to design a CO and CO
₂
concentration measurement system. The system was applied to measure the CO and CO
₂
concentrations in three volcano areas: Mt. Welirang, Mt. Bromo, and Mt. Panderman. The system measures with a time response of fewer than 2 seconds with sensitivity o ±0.14 kΩ/ppm for CO measurement and ±0.05 V/ppm for CO
₂
measurement and the accuracy ±0.04 ppm for CO and ±9.8 ppm for CO
₂
. The system measurements range from 0 - 15 ppm for CO measurement and 300 - 550 ppm for CO
₂
concentration with the resolution of 0.01 ppm for CO and 1.0 ppm for CO.