Guide for Purchasing Standardized Gases for Calibration

When deciding which standard gases to purchase for calibration, there are some important considerations that will help guide your purchase:

1. Determination of concentration of the gas to be purchased. The concentration of the standard gas is the first consideration. It needs to be at a concentration level that is appropriate for calibration of the instrument.
2. Determination of proper regulator for the standard gas tank. A regulator is needed to provide a consistent flow of gas to the instrument at a certain rate. At our facility, we use on-demand regulators that require the pumps within our instruments to pull the gas from the standardized tank. If this is not an option, other regulators are acceptable, just use a T-junction when connecting to the instrument to protect the instrument from damage.
3. Determination of the size of tank to order. Consider how many calibrations can be performed with the volume of gas purchased. Each calibration for the F-920, 940, and 960 will take around 0.3 liters of standard gas.

Below is an example of a standard order our company would make to Air Liquide for a 1.5ppm ethylene standardized gas tank for calibration of the F-940.

Air Liquide is a multi-national company that can deliver products to most business locations worldwide. You may look at www.airliquide.com for your local office.

Air Liquide America Specialty Gasses LLC

Telephone 425-931-8303 or 800-814-4642

A sample order for 34 Liter canister of appropriate calibration gas for an F-940 or F-950 would include the following (Note, these are Air Liquide’s unique product numbers):

Part Number: A0909352 Scotty 34

Description: 2 Component Mix, Balance Air, Gas 34, NR

AIR BAL

ETHYLENE 1.5 PPM

Phase: Cylinder Gas Measurement: Mole Class: N/A

Size: 34

Your gas vendor will do their best to meet your specified concentration and will provide a certificate of analysis with your gas showing what they have delivered. Be certain to use the actual value on the certificate of analysis as it may differ from what you have ordered.

If you don’t already own a regulator, you must buy one. The following is the ordering information for the on-demand style regulator that we typically use. (Note, these are Air Liquide’s unique product numbers)

Part Number: A0315576

Description: Q114DRFRC10 – M14 Demand Regulator

0 – 3 LPM @ 3’