The invention comprises a gas recycling system comprising: a) a source of gas having a predetermined purity (28); b) an application system (6) that uses said gas and adds contaminants to said gas; c) an adsorption system (1) for removing said contaminants from said gas to produce a purified gas, and a waste gas; d) a gas purity analyzer (100) for measuring the amount of said contaminants in said waste gas; e) conduits ((5), (8), (9) (13) and (15) connecting the gas source (4) to said application system, said application system (6) to said adsorption system.