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Air Liquide in the value chain

Stack testing

A stack test is a procedure for sampling a gas stream and then using that sample to determine a facility’s ongoing compliance with the emissions limits set forth by U.S. EPA regulations. Air Liquide offers ±1% Scott™ brand EPA protocol gases and CEM DAILY STANDARDS™ as calibration standards, as well as ALPHAGAZ™ brand pure gases engineered to help you accurately test and measure emissions monitoring analyzers. We also offer GMACS (Gas Manufacturer's Alternative Certified Standards) hydrogen chloride gas mixtures, an EPA-approved class of calibration standards specifically for monitoring HCl emissions at CEMS installations. Our extensive inventory of gas handling and distribution equipment allows you to safely store, handle and deliver these gases to your applications.


Equipment for specialty gases