What Is Calibration Gas Used For?

Gas monitors are a critical component of safety systems designed to raise an alarm when the amount of a particular gas exceeds an acceptable limit. The accurate and consistent monitoring of gas levels is crucial to the safety of personnel and the general public.

Calibration gas plays a vital role in ensuring the safety and testing of portable gas detectors and fixed gas detection systems. Operating with any type of gas, especially in confined spaces, a gas detector is absolutely critical to maintaining the safety of those involved. Without proper gas detection, workers could be put at risk of injury or severe illness due to exposure of harmful gases. In order for the gas detector to serve its correct purpose, it first needs to be accurately calibrated.

What Is Calibration Gas?

Calibration gas is a combination of gaseous components used as a reference in the calibration of analytical instruments, including gas analysers and gas detectors. These reference gases are a mixture that is generally compressed, existing of one initial gas that is enhanced by one or more components. Calibration gas can contain toxic and flammable gases.

To be a calibration gas, the gas must be traceable to a national or international standard. Traceability refers to the unbroken chain of comparisons to an acceptable international standard. The calibration gas standard shows a known analyser response to a certified chemical component concentration. For calibration gases, preparation tolerance (PT) and certification accuracy (CA) are critical.

What Is Calibration Gas Used For?

In essence, calibration gases are used to calibrate and set the gas detectors to ensure they are functioning accurately. The only way to be sure that a gas detector is working correctly is to test it with known calibration gas.

Generally, calibration gas is used for the calibration and bump testing of portable gas detectors and fixed gas detection systems. The mixture of gases has been certified to be prepared gravimetrically, using National Institute of Standards and Technology (NIST) traceable weights.

Calibration is crucial for all testing instruments for accuracy, and the calibration gas helps to establish a known response to a certified chemical component concentration. Using the right calibration gas for an instrument ensures that the gas monitor or detector is in good working order and compliance with manufacturers recommendations as well as Australian standards.

Why Calibration Gases Are Important

Calibration gases are essential for optimal performance and smooth efficiency. Keeping your instruments in good working order, calibration gases are also crucial to ensuring everyone handling gas detectors and fixed gas detection systems are safe.

Calibration of instruments is the process of applying a known concentration of a specific gas to the detector while it is in calibration mode. The instrument analyses the gas and adjusts the instrument response to match the gas value. This process ensures and maintains the accuracy of the gas detector. Furthermore, calibration also checks on all other aspects of the detector, including alarms, display, general condition etc.

An accurately calibrated gas detector will provide accurate readings of traces of various gases in the air; which may be helpful in situations such as gas leaks where immediate evacuation or medical attention may be required. When gas detectors have not been properly calibrated and record gas traces as being lower than they are, the outcomes have the potential to be catastrophic.

When it comes to calibration gas standards, there are three main levels: Primary reference gas mixtures, secondary reference gas mixtures, and working gas standards.

Primary Reference Gas Mixtures

Sitting at the top of the traceability chain, primary reference gases (PRGM) are the highest quality standards available for commercial use. PRGMs are prepared in direct comparison to the Primary Standard Material and offer the lowest uncertainties possible. PRGMs are typically only used for the most sensitive calibrations where the best uncertainty is required.

Secondary Reference Gas Mixtures

Secondary reference gas mixtures (SRGM) are prepared gravimetrically and calibrated against PRGMs, where the analytical value and analytical uncertainties are on the certificate. A lab offering SRGM must be accredited to ISO17025 or equivalent. SRGMs are the most popular choice of calibration gas as they balance low uncertainties and are generally the most cost-effective choices for gas calibration, especially in large volume cylinders.

Gas Calibration Supplies

Newcastle Safety Servicing supplies calibration gas for all portable and fixed gas detection equipment. For bump testing through to a complete calibration test station, we can provide single, dual, four & five gas mixtures. Newcastle Safety Servicing is fully accredited, and our gas calibration services adhere to strict regulatory requirements. Get in touch with one of our technicians today to learn more about our gas calibration services.