GC Calibration Standards Vendor

[cdrras]

Does anybody know of a couple of vendors that sells GC calibration standards or gas cylinders with reagents of suitable purity?
The gases I am currently looking for are:
1. Hydrogen
2. Carbon Dioxide
3. Carbon Monoxide
4. Methane

If possible, I'm looking for a QT cylinder size (US DOT Spec: 4B-240)

I have already looked at Sigma-Aldrich and Fisher Scientific, but I'm thinking I might be able to find them somewhere else with lower costs. If anybody has any information that they would like to pass along, it would be greatly appreciated. Thanks

 

[mbt22]

BOC (part of Linde now) or Air Products will sell you any of these.

 

[JLSeagull]

Each plant usually works with the distributers in that area. The analyzer manufacturers also have distributors that they work with. Discuss these potential sources if applicable.

Search for specialty gas or GC grade gas. Some of the players may include Airgas, Air Liquide formerly Scott Specialty Gas, High Purity, MathesonTriGas, Mesa Gas, Praxair, etc.