Gases for Industrial Emissions Monitoring

Air Liquide manufactures gas mixtures in small portable and larger refillable cylinders for the calibration of emission measurement equipment. These gases are traceable to international standards and support QAL1, QAL2, QAL3 and AST calibration applications.


Calibration gases in accordance with EN 14181


Accredited and non-accredited gas mixtures to support calibration application in accordance with QAL1, QAL2, QAL3 and AST quality assurance procedures.

QAL1, is the one-time evaluation procedure that validates whether a measuring system meets the uncertainty requirement according to EN-ISO 14956, which is performed by the manufacturer or supplier of the measuring equipment for obtaining the type approval. For this application, Air Liquide offers stable calibration mixtures according to the procedure with an uncertainty of ±2%

QAL2, provides the procedures for the periodic calibration and validation of the automated measuring system. This procedure applies after installation and execution of the functional tests. For this application, Air Liquide offers stable, accredited calibration mixtures to ISO17025 according to the procedure with an uncertainty ±2%.

QAL3, describes the quality control performed by the operator and requires that the measurement system continues to function within the applicable uncertainty requirement. For this application, Air Liquide offers stable calibration mixtures according to the procedure with an uncertainty of ±2%

​​AST​, this annual inspection of the measurement system is performed by an independent measurement body or laboratory​ and verifies whether the measurement system still operates within the applicable uncertainty requirement​.​ For this application, Air Liquide offers stable, accredited calibration mixtures to ISO17025 in portable cylinders according to procedure with an uncertainty ±2%.


Gaz spéciaux Alphagaz™ Air Liquide

Environmental authorities and legislation require the use of accredited calibration mixtures with recognised international traceability and validated uncertainty conformation for certain emission measurement applications.

The quality of accredited calibration mixtures to ISO17025 is independently verified through the accreditation process, ensuring increased confidence and eliminating the need for any supplier audits.

These certified reference materials for the calibration and validation of analytical systems are produced by Air Liquide under ISO/IEC 17025 calibration laboratory accreditation and or ISO/IEC 17034 accreditation as a manufacturer of reference materials.


  • Convenient and user-friendly packaging, ranging from small portable to large cylinders.
  • Gas handling equipment to facilitate mobility during use
  • Available with LABTOP™ built-in pressure regulator
  • There is an option for cylinders to be trackable by means of barcodes for optimal stock management

Air Liquide supporting emissions compliance


Testimonial - IRIS Emissions Services Limited

Air Liquide has been supporting IRIS Emissions Services for many years. This generally involves the provision of calibration gases for continuous emissions monitoring systems (CEMS) and process analysers, that are installed on industrial plants and the marine sector. These can be demanding applications and analyser performance (and therefore good service and maintenance) is critical to efficient plant operation and compliance.

Having a reliable, high quality supply of the calibration mixtures is paramount to our activity on a variety of industrial sites, most notably waste incinerators. Our clients expect our service and maintenance offering to be inclusive and pain free and having Air Liquide's gases on hand is a key component to doing so.

Alison Sampson, co-owner and director at IRIS


Air Liquide's calibration gases

As a partner to IRIS, Air Liquide understands the compliance regulations associated with the emissions monitoring 9QAL1-3, AST, accreditation) and we are able to support IRIS from initial commissioning through to on-going operation and servicing.

Do you have any questions about industrial emission measurements?

Please complete our form below and we'll come back to you as soon as possible