Complete Selection of Calibration Gas & Equipment


Calibration Gas 101

The following will describe various aspects of calibration gas, equipment and procedures.

Gases / Cylinders / Regulators

General Rule

  • Reactive gases are blended in aluminum cylinders
  • Non-reactive gases are blended in steel cylinders
    See table of gases below


  • Reactive gases are never blended in steel cylinders; however non-reactive gases will be blended in aluminum cylinders at the customer’s request.

The gas detection instrument defines the type of regulator:

  • Fixed Flow – regulator has a preset flow rate from .2 liters per minute (lpm) to 6.0 lpm. The manufacturer will specify the required flow rate for calibration.
    • We offer a select-a-flow regulator. A single regulator that has selectable fixed flow rates from 0.0 to 3.0 lpm. Useful for customers with various brands of instruments with different flow rates.
  • Demand Flow – some instruments have an internal pump that draws air into the unit. A demand flow regulator (DFR) will match the flow rate that the draw pump generates.

The cylinder will define the regulator in terms of thread connection:

  • 17L steel & 34L steel: CGA 600 (external thread on cylinder/internal thread on regulator)
  • 34L aluminum, 58L aluminum, 74L aluminum & 103L steel: CGA C10 (internal thread on cylinder/external thread on regulator)
  • 221L steel: CGA C165 (external thread on cylinder/internal thread on regulator)

The gas will define the material of construction of the regulator:

  • Reactive gases require stainless steel construction and Teflon tubing.
  • Non-reactive gases may use nickel plated brass construction and Tygon tubing.

The OEM Will Define the Calibration Gas Concentration

  • Generally, the manufacturer will recommend a gas concentration in the mid-range of the sensor; if a Carbon Monoxide (CO) sensor has a range of 0 – 200 ppm, the manufacturer will recommend a CO concentration of 100 ppm.
  • More precisely, each manufacturer will recommend a specific concentration or blend that will be unique to their instruments, and may be required for the auto-calibration function to work properly.
  • Also, it is not uncommon for manufacturers to recommend using a concentration that is at or near the lower alarm level, which usually is a contradiction of the “sensor mid-range” recommendation.

Part Numbering System

We utilize a hybrid smart number – the part number reveals important details about the product.

  • Format: AA-BBB-C-DDDD
    • The first two characters (AA) define the calibration gas: “01” = Ammonia
    • The next three characters (BBB) are sequential and define the concentration.
    • The next character (C) defines the balance gas: “A” = Air, “N” = Nitrogen (N2)
    • The next characters (DDDD) define the cylinder size and material of construction:
      • “17S” = 17 liter steel
      • " 34S” = 34 liter steel
      • “34A” = 34 liter aluminum
      • “58A” = 58 liter aluminum
      • “74A” = 74 liter aluminum
      • “103S” = 103 liter steel
      • “221S” = 221 liter steel

We add part numbers on a regular basis:

  • If you need a concentration that is not listed in our catalog, please inquire.
    You can quote a concentration that falls within the range of concentrations in our catalog – pricing will be the same as concentrations listed.

Reactive & Non-Reactive Gases



Ammonia (NH3)

Benzene (C6H6)
Chlorine (Cl2) Carbon Dioxide (CO2)
Hydrogen Chloride (HCl)
Carbon Monoxide (CO)
Hydrogen Cyanide (HCN) n-Hexane (C6H14)
Hydrogen Sulfide (H2S) Hydrogen (H2)
Nitric Oxide (NO) Isobutylene (C4H8)
Nitrogen Dioxide (NO2) Methane (CH4)
Nitrous Oxide (N2O) Oxygen (O2)
Sulfur Dioxide (SO2) n-Pentane (C5H12)
  Propane (C3H8)
  Zero Air
  Zero Nitrogen (N2)

Aluminum Cylinders
Steel Cylinders
34 Liter (34A)
17 Liter (17S)
58 Liter (58A)
34 Liter (34S)
74 Liter (74A)
103 Liter (103S)
221 Liter (221S)

Delivery Lead Times

Stock Items – Same day or next day shipment

Non-Stock Items:

  • Non-reactive gases and blends of non-reactive gases:
    • Generally, 3-4 days
      Same day is possible if we know early in the day (allowing time for blending, mixing, analysis & labeling)
  • Reactive gases and blends including at least one reactive gas:
    • 7-10 days
      Shorter times for Reactive blends are possible, including next day under certain circumstances

MSDS & Certificates of Analysis

We have a MSDS for all of the blends that we sell. We use the MSDS library of Airgas, the supplier of our primary 1% NIST traceable gas standards. We also generate a Certificate of Analysis for each cylinder or frequently the CofA will cover a group of cylinders. Both documents are stored in electronic format.

We do not supply the MSDS as a matter of course. We supply them upon request only. A Certificate of Analysis is included with each cylinder

To request a MSDS, use the part number as a reference.

We can fax, mail or email these documents.

Gas Dynamics, LLC
| 800-916-8177
46410 Continental Drive • New Baltimore, Michigan 48047 | V: 586-329-1859 | F: 586-421-5123 | Email Us