Atmospheric Monitoring for Hydrogen Sulfide by Photorateometric Analysis

A new method for analysis of the hydrogen sulfide (H₂S) content of the atmosphere is by photorateometric measurement. This detection method consists of a surface chemically treated with lead acetate enclosed in the chamber. Reaction with H₂S causes a color change. A photocell response is produced by “rate of change” electronics, the output of which is proportional to the first derivative of the photocell output. This first derivative signal is a measure of H₂S concentration. An output linear with concentration is obtained. A range of measurement may be obtained in parts per million (ppm) and parts per billion (ppb) with extreme accuracy. Response time using the rateometric technique is sufficiently fast to allow plume characterization using surface vehicle or aircraft mounted analyzers.