glsafety

While preparing calibration gas mixtures, two types of measurements are made – • volumetric or gravimetric measurement - measuring what goes into the cylinder; requires a calibrated pressure or flow device (volumetric) or a calibrated balance (gravimetric) • measurement based on analysis - measuring what comes out of the cylinder; requires a gas analyzer and several reference gas mixtures High quality gas mixtures are manufactured gravimetrically and analyzed with an accredited process, outlined on the cylinder certificate. Specialty gas mixtures are also classified into one of the following categories, based on how they are made, tested, analyzed, or certified. Traceable Gas Mixtures Traceable mixtures are those gas mixtures that have been manufactured using traceable weights and measures. In other words, regardless of the method is used to manufacture the mixture, the instrumentation had undergone a traceable calibration.  Certified Gas Mixtures Certified mixtures are the ones th