HARMFUL GAS DETECTING METHOD, AND APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a harmful gas detecting method and apparatus that can continue to reliably measure harmful gas contents over a long period.SOLUTION: In a harmful gas detecting method by which the measurement object gas is brought into contact with a granular detection agent that changes its color when coming into contact with any harmful gas content and any color change of the detection agent is optically detected by color change detecting means, the average grain size of the detection agent is set to be less than 1/5 of the shortest dimension of the range of detection by the color change detecting means but not less than 200 μm.SELECTED DRAWING: Figure 1