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SPECIALTY GAS DIVISION: Services & Contacts | Bulk Gases | Micro-Bulk Gases | Laser Systems | Specialty Gases | Gas Equipment
Central Cryogenics offers a complete line Specialty Gases and Gas Mixtures, including EPA Protocol Gases
Recent Installations Data Online
Laser Cutting Machine
Micro-Bulk Delivery

We can meet the quality your industry demands:

  • Pharmaceutical/Biotechnology
  • Chemical/Petrochemical
  • Environmental
  • Food/Food Service
  • Healthcare
  • Laboratories/Research/Universities
  • Semiconductor
  • Metal Fabrication
  • Life Sciences
Regardless of your need, our highly-skilled Gas Specialists are capable to manufacture specialty gas mixtures to your exacting specifications meeting the most stringent standards for quality, critical for your controlled processes or vital instrumentation.
Pure Gases Gas Cylinders
Central Cryogenics offers the five major grades of gas purity specifications.
  • Research Grade
  • Ultra High Purity
  • Zero
  • High Purity
Compressed Gas Cylinders
Non-refillable Steel Cylinders
Portable Reactive Gas Cylinders
Life Sciences & Research: Gases & Equipment
CENTRAL CRYOGENICS offers a complete line of Laboratory Grade Gases and Specialty Gas Handling Equipment for the Life Sciences Industry.
Download Life Science Industry Gases, Equipment & Services [PDF]  
Central Welding Supply Gas Specifications
Download Specialty Gas Specifications [PDF]  
Certificates of Conformance (COC) Certificates of Analysis (COA)
A COC defines gas specifications for product distriubted as "UHP" grade. This certification provides quality assurance for gases filled within a batch.

COC's are available on request for all the gases we fill and distribute.

A COA defines gas specifications and quality assurance for "UHP" grade gases that is performed on a specific cylinder or vessel.

COAs may be requested at the time of gas order for an additional charge.
Contact Gas Specialist, Gary Emerson for further information regarding our gas certifications. CALL: (360) 454-5550
Gas Mixtures

Central Cryogenics offers a wide variety of custom gas and liquid mixtures to suit the most stringent process control or analytical requirements. We supply three grades, covering most specification requirements.

The Mixture Specifications Table shown below outlines each of the three grades - Primary Standard, Certified Standard, and Unanalyzed Mixture - and their tolerances. If you require accuracies which exceed our stated tolerances, our Gas Specialists can assist you.

Grade Concentration
Primary Standards** 20 ppm to 4,999 ppm
5,000 ppm to 1.9%
2% to 49%
±5% of component
±2% of component
±1% of component
±1% of component
±1% of component
±0.02% absolute
Certified Standards** 1 ppm to 99 ppm
100 ppm to 0.99%
1% to 49%
±20% of component
±10% of component
±5% of component
±5% of component
±2% of component
±1% of component
Unanalyzed Mixtures 0.1% to 0.99%
1% to 50%
±15% of component
±10% of component
Not Applicable
Not Applicable

*These tolerances may vary from those stated in the table under the following situations:

  • Mixtures containing low molecular weight components such as hydrogen and helium, depending on their concentration.
  • Mixtures containing components that present adsorption, stability, or other blending problems.
  • Multicomponent blends, depending on the type, number, and concentration of the components.

**Depending on the component concentrations, it is sometimes possible to produce gas mixtures with tolerances that surpass those indicated. 

Portable Non-refillable Cylinders
Central Cryogenics offers a variety of both Non-refillable Steel Cylinders and Portable Reactive Gas Cylinders to accommodate your specific needs.
Non-refillable Steel Cylinders  

A convenient and cost-efficient way to handle calibration gas mixtures... these smaller-sized, lightweight cylinders require no deposit or monthly rental charge. They are easier to handle, less expensive to ship, and use very little space. They also eliminate over-purchasing when only small quantities are necessary.

These steel cylinders are recommended for non-reactive gas mixtures and pure gases such as argon, helium and nitrogen. They combine a convenient, portable size with a wide range of capacities (from 17 liters (0.6 cu ft.) to 550 liters (19.4 cu ft.)) to handle any field calibration requirement.

Portable Non-Refillable Cylinders
See Cylinder Specifications
Portable Reactive Gas Cylinders  

Offering mixture stability in a lightweight, portable package... these compact, lightweight aluminum cylinders are recommended for gas mixtures that are not stable in steel cylinders.

Typical components blended in these packages include ammonia, chlorine, hydrogen sulfide, nitric oxide, nitrogen dioxide and sulfur dioxide.

They are available in capacities from 11 liters (0.4 cu. ft.) to 104 liters (3.7 cu. ft.) and are conveniently transported in a NorLab carrying case or bag. They are non-refillable, except the “3A” cylinder, which is a refillable package.

Portable Reactive Gas Cylinders
See Reactive Gas Cylinders
Compressed Gas Cylinders
For customers requiring gas in a transportable format and/or with volume requirements up to 175,000 cubic feet per month, cylinders can represent a convenient supply source for their gas requirements.
Cylinders are defined by four main characteristics:
Gas form - Compressed gas, refrigerated liquid (carbon dioxide, nitrous oxide), dissolved gases (acetylene), or cryogenic liquids.
Gas type - Oxygen, nitrogen, argon, acetylene, carbon dioxide, hydrogen, helium, rare gases, specialty gases, nitrous oxide, chemical gases and liquids, medical gases.
Gas purity - Up to 99.9999%.
Cylinder - Size (volume) and pressure, varying from country to country.
Compressed Gas Cylinders
Cylinders can be supplied individually or bundled together as 6 or 16 cylinder packs and emptied as a unit. Materials of construction include aluminum, steel, light alloy, composite materials, as well as special porous interior materials for acetylene.

Central Cryogenics employs inside treatments and special filling procedures to comply with specifications. We also perform regulation checks and re-testing of cylinders.



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