Gas Chromatograph Hydrogen Gas Safety (introduction)

Gas Chromatography


Gas Chromatograph Hydrogen Gas Safety
Hydrogen gas (H2) is used for the flame ionization detector (FID) in gas chromatographs (GC). Hydrogen is a dangerous gas that explodes easily. This page describes the potential dangers and precautions for the safe use of hydrogen gas in gas chromatographs.

A cylinder is a sealed container that can contain a gas or liquid. "High-pressure gas cylinders" filled with a gas at high pressure are often used with analytical instruments. When using a high-pressure gas cylinder as a gas supply, take instructions from the high-pressure gas cylinder supplier to ensure safety and prevent accidents. High-pressure gas cylinders are color-coded according to the type of gas they contain, as follows: hydrogen - red; oxygen - black; nitrogen - gray; helium - gray; argon - gray; carbon dioxide - green; acetylene - brown. As hydrogen is a flammable gas, a left-hand thread(CGA-350) is used at the cylinder outlet. (Helium cylinders also use a left-hand thread in some cases.)

Hydrogen Gas Properties

Hydrogen is a dangerous gas which can easily explode if handled improperly.
When hydrogen is used, be sure to understand the characteristics and proper handling of this gas.

  • Colorless, odorless gas
  • Wide combustion range, between 4 vol% and 75 vol% mixture with air
  • Ignites with extremely low energy.
  • Easily accumulates near the ceiling, as it is lighter than air.
  • Quickly mixes with air due to its high diffusion rate.
  • Rapid expansion causes automatic ignition.
  • The hydrogen flame is invisible, and easily carried by drafts.
  • When mixed with a halogen gas such as chlorine, hydrogen explodes on direct exposure to sunlight.


Precautions related to hydrogen gas are also listed in the gas chromatograph instruction manual.
Also read these precautions.

On this page, actions that must NOT be performed and actions that must be performed are indicated using the following two icons.

Indicates an action that must NOT be performed
Indicates an action that must be performed.
Additional information to improve the safety or promote better understanding.