What is calibration gas?
A calibration gas is a mixture of gaseous components used as a comparative reference in the calibration of analytical instruments, such as gas analysers or gas detectors.
Calibration is important for all testing instruments and the calibration gas is a means of establishing a known response to a certified chemical component concentration.
Mixtures having been produced or calibrated within the scope of an ISO17034 or ISO17025 accredited organisation. Accreditation proves the producer’s technical capability in measurement, and stated traceability to SI units, having been thoroughly assessed by the relevant national testing authority. All CAC Gas Accredited mixtures will be made by a producer whose accreditation is recognised under the ILAC MRA**, so they are accepted globally. These mixtures meet the requirements of:
- ISO Guide 30:2015 (Clause 2.1.1 or 2.1.2)
Mixtures manufactured, analysed, or tested by specific, documented methods, and come with a certificate stating the method(s) used. Such methods may be required by industry, regulatory bodies, or internal/site standards. These methods exist to promote similar product quality and properties for a single product type from various manufacturers, or to ensure a minimum product quality. Methods may be nationally or internationally recognized, such as those from ASTM, ISO, or US EPA.
Mixtures are manufactured using traceable weights and measures. This means that no matter what method is used to manufacture the mixture*, the instrumentation (scales/balances, mass flow controllers, pressure gauges, etc.) used in the manufacturing process has undergone a traceable calibration. Traceability requires that the calibration of the instrumentation be ISO17025 certified. Calibration certificates for relative instruments are kept on file and referred to on the mixture certificate if required. This shows an unbroken chain of measurements or calibrations all the way to the accepted international primary reference materials.