Class 2 Gases Explained | NZ Dangerous Goods Guide

What Are Class 2 Gases?

Class 2 gases are substances transported in a compressed, liquefied or dissolved gas form. These gases can present hazards such as flammability, toxicity, pressure or asphyxiation, which is why they are regulated under dangerous goods transport rules in New Zealand and internationally.

A substance is classified as a gas when it:
  • Has a vapour pressure greater than 300 kPa at 50°C
  • Completely gaseous at 20°C at a standard pressure of 101.3 kPa
Common Examples of Class 2 Gases
  • LPG / Propane
  • Butane
  • Oxygen
  • Nitrogen
  • Carbon dioxide
  • Aerosols
  • Refrigerant gases


Class 2 Gas Divisions

Class 2 gases are divided into three hazard divisions: 

  • Class 2.1 Flammable Gases (e.g. Propane, Butane)
  • Class 2.2 Non-Flammable, Non-Toxic Gases (e.g. Nitrogen, Carbon dioxide)
  • Class 2.3 Toxic Gases (e.g. Chlorine, Ammonia)

Correct classification determines cylinder requirements, labelling, segregation and transport rules.

Dangerous Goods Training (NZ)

If you handle or ship gases or other dangerous goods by road, proper training is required under NZS 5433 and the Land Transport Rule: Dangerous Goods 2005.

Enrol in our online training:

Shippers of Dangerous Goods by Road (NZ)
We are an online training platform that helps shippers and professionals understand and comply with dangerous goods requirements.

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