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Safety Data Sheet · SDS / MSDS

Hydrogen H₂ — SDS

Hydrogen, compressed · Industrial hydrogen
UN No: 1049CAS: 1333-74-0Class: 2.1 — Flammable gasSignal: Danger
4
0
0
NFPA 704: Health 0 · Fire 4 · Reactivity 0
Blue = health · Red = flammability · Yellow = reactivity.

Hazard identification (GHS)

  • Extremely flammable gas (H220) with a very wide flammable range and very low ignition energy.
  • Contains gas under pressure; may explode if heated (H280).
  • Burns with an almost invisible flame; lighter than air and collects at ceiling level.

First-aid measures

Inhalation: remove to fresh air; give oxygen or artificial respiration if needed; get medical help. Treat any flash burns conventionally and seek medical attention.

Handling & storage

  • Eliminate all ignition sources; use explosion-proof, earthed/bonded electrical equipment and ventilation.
  • Store cylinders upright, capped, below 52 °C in a well-ventilated area away from oxidisers.
  • Leak-test with soap solution only — never a flame; provide high-level ventilation as hydrogen rises.

Physical & chemical properties

AppearanceColourless gas
OdourOdourless
Molecular weight2.02
Boiling point−252.8 °C
Flammable limits in air4 – 75 %
Auto-ignition500 °C
Relative density (air = 1)0.07

Stability & reactivity

Stable. Violently reactive with oxidisers, halogens and oxygen. Hazardous decomposition: none (product is elemental).

Transport information

Hydrogen, compressed — Class 2.1, UN 1049, Label: Flammable gas.

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This is a summary Safety Data Sheet for reference. For the full signed SDS, grades, purity and cylinder options, contact our team.

Frequently asked questions

Hydrogen (H₂) is classified as 2.1 — Flammable gas. Yes — it is a flammable gas.
Hydrogen is shipped as Hydrogen, compressed — Class 2.1, UN 1049, Label: Flammable gas.
The CAS number of Hydrogen is 1333-74-0.
This page is the IIGAS Hydrogen (H₂) Safety Data Sheet summary. For the full signed SDS document, contact IIGAS at marketing@iigas.com.

Reference summary only, compiled by International Industrial Gases Ltd (updated 2026-07-20). Values are for the compressed-gas form. It does not replace the full signed Safety Data Sheet supplied with the product; always follow the SDS provided with your cylinders.

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