Analysis of hydrogen sulfide in hydride gases

A method of measuring hydrogen sulfide concentrations in hydride gases comprising the steps of:

• a) providing a sealed vessel, said vessel having a gas inlet to receive a stream of hydride gas, a gas outlet to remove said stream of hydride gas and a metal acetate substrate, said metal acetate being selected from the group consisting of lead acetate and zinc acetate and said stream of hydride gas containing a concentration of hydrogen sulfide gas;
• b) exposing said acetate substrate to a calibrated hydrogen sulfide-containing primer gas to pre-darken said acetate substrate;
• c) introducing said stream of hydride gas through said gas inlet to contact said acetate substrate with said stream of hydride gas;
• d) reacting said hydrogen sulfide gas contained in said stream of hydride gas with said acetate substrate to modify optical properties of said acetate substrate;
• and
• e) measuring said optical properties of said acetate substrate to determine said concentration of said hydrogen sulfide gas contained in said stream of hydride gas with a substantially linear relationship between said hydrogen sulfide gas and darkness of said acetate substrate.