ISO 17025 / ISO 17034

Precision Calibration Gases

CalGas Warehouse is a calibration gas supplier that is an ecommerce site focused on providing American made industrial calibration, bump, specialty and rare gases to our diverse clientele. We are direct vendors for four of the largest industrial gas manufacturers in the country, Portagas/Praxair and Gasco/Airgas. We list the top 200 mixtures sold in the market. Our diverse catalog allows us to solve complex mixture and logistical issues to fit your needs. If you don’t see your product listed, please fill out the online request or reach out to us by phone by calling 301-698-2708.

Our priority at CalGas Warehouse is to offer solutions that save you time and money, while leaving minimal impact on the planet.

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Wikipedia defines Calibration Gas as follows:

“A calibration gas (also referred to as CalGas) is a reference gas or gas mixture used as a comparative standard in the calibration of analytical instruments, like gas analyzers or gas detectors, Therefore, a calibration gas has to be a precisely defined nature of composition, like zero gas or span gas; for example 50 ppm Carbon Monoxide in Nitrogen.

To be a calibration gas, that gas must be traceable to a national (NIST) or international standard. Traceability is the unbroken chain of comparisons to an acceptable international standard. The calibration gas standard establishes a known analyzer response to a certified chemical component concentration. In the calibration preparation tolerance (PT) and certification/analytical accuracy (CA) are of utmost  importance.

Preparation Tolerance (PT) is the concentration range that includes minor component and concentration. PT is actually measured in range of concentration. For instance, a cal gas of 50 ppm CO and balance Nitrogen having PT +/- 10% contains between 450 ppm and 550 ppm. PT can be minimized by using latest technologies is decided on the basis of the manufacturing such gases. Preparation tolerance is decided on the manufacturer’s experience and the customer’s requirement.

Certification/analytical accuracy (CA) is defined as the agreement of measured values with its true value. Certification values are determined statistically, considering the uncertainties accompanied by the international standard (reference standard) to which it is traceable, instrument uncertainty and the instability (reactivity) of the gas in the container.

CalGas Warehouse laymen’s terms on Calibration Gas

A calibration gas is a defined concentration/mixture of gases that are used to calibrate to an acceptable defined range (span) within a gas detector. ALWAYS check with the manufacturer for the exact concentration your gas detector requires. NEVER use expired gas and check with your safety director or supervisor if there is any uncertainty or hesitancy on what your required cal gas(es) might be. Please refer to our commonly used gas detection terms, if you are unsure of terms or abbreviations.

We used the most commonly searched terms and abbreviations on our website in hopes it might answer your question or concern. Please use the chat feature or contact us should you need any assistance.