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Nitric Oxide

High-purity nitric oxide

Air Liquide manufactures nitric oxide pure gas with minimum purity of up to 99.99%. It is used in a variety of applications, including semiconductor manufacturing. Nitric oxide as a pure specialty gas is also available in nonreturnable Mini-MixTM Transportable cylinders when smaller quantities of gas are needed for laboratory and industrial hygiene and safety applications.

Air Liquide provides nitric oxide as a component in many gas mixtures, including two-component, three-component and multi-component mixes that are guaranteed interference-free with either carbon monoxide or carbon dioxide certified. They are for use in the environmental industry. Nitric oxide in nitrogen mixtures are used as a span gas calibration mixture in engine emissions testing in the automotive industry. They are ISO 17025 accredited and Part 86 compliant. Nitric oxide gas mixtures are also used in industrial hygiene and safety and laboratory applications.



EPA Protocols

Nitric oxide gas mixtures are manufactured as Scott brand EPA protocols and are instrumental in helping you avoid non-compliance fines and downtime caused by inaccurate instrument calibration. Air Liquide’s specialty gas manufacturing facilities are registered participants of EPA’s Protocol Gas Verification Program (PGVP). Protocol standards are dual-analyzed, and for each reactive component, two separate analyses are performed and analyzed directly against metrology institute standards to determine the concentrations. Certificates of Accuracy are provided with each cylinder.

Low NOx EPA Protocols with concentrations as low as 0.1 ppm for RATA applications

Low NOx EPA Protocol Gases from Air Liquide are unique in the environmental industry. With guaranteed ±1% accuracy in concentrations as low as 0.1 parts per million, they provide the highest reliability and level of confidence for meeting environmental compliance requirements. They are NIST or VSL-traceable and certified for nitric oxide, NOx or both and are invaluable for use by stack testers and utilities. They can be used for Relative Accuracy Test Audits (RATAs). A detailed Certificate of Accuracy meets EPA requirements.

Identification of reference standards Scott Low NOx EPA Protocol Gases are dual-analyzed using EPA G1 or G2 methods. Two independent analyses are performed after the blending process has been completed in order to determine the concentration for each component. As per EPA requirements, the values obtained from these analyses must agree to within ±1%. Air Liquide also manufactures Interference-Free™ Low NOx EPA Protocols with carbon monoxide or carbon dioxide certified, creating the only dual-component low NOx protocol gas available today.


Nitric oxide gas mixtures are also manufactured as CEM DAILY STANDARDS and used in applications where the use of EPA protocol gases is not required. Zero blend tolerance is available as a result of our proprietary ACUBLEND™ technology, so that multiple cylinders that exhibit identical concentrations may be ordered. This minimizes the need to recalibrate each time you change out a cylinder.

Related Supply Modes and Services

Air Liquide packages nitric oxide pure gases and gas mixtures in a variety of high-pressure cylinders, including stainless steel, aluminum and nonreturnable Mini-Mix Transportable cylinders, depending on the grade and concentration desired as well as your application. Air Liquide offers a wide range of services to try and meet each customer's needs.