Gas cylinder markings
Gas cylinder marking for oxygen
Gas cylinders and their hazardous properties can be recognised readily identifiable by recognition of gas cylinder markings as follows:
Class 2.1 Flammable gas
Examples: LPG, hydrogen, acetylene
Class 2.2 Non-flammable, non-toxic gases
Examples: compressed air, nitrogen, argon, carbon dioxide, helium.
Class 2.2, Sub-risk 5.1
"Oxidising gas"
Examples: oxygen, nitrous oxide, Entonox (50% oxygen, 50% nitrous oxide).
Class 2.3 Toxic gas
Examples: methyl bromide, anhydrous ammonia, chlorine.
Under the Dangerous Goods Safety Management Legislation gas cylinders are required to be labelled with the following, as shown below:
- class label and any subsidiary risk labels
- the proper shipping name
- a four digit United Nations number
- Manufacturer/importer’s name.
Figure 1 Gas cylinder markings
Gas cylinder marking for oxygen
In addition, to the markings shown in Figure 1, a cylinder will also be required to have other markings which are stencilled onto the cylinder near the neck of the cylinder these will include:
- the tare weight
- serial number
- owner’s name
- test pressure
- retest date
- manufacturer’s stamp
- water capacity.
Water capacity is the equivalent water volume of the cylinder in litres.
Manufacturers paint gas cylinders using a colour coded system that is useful in identifying gas cylinders. You should consult the manufacturer’s product catalogues for colour charts with this information.
Last updated 21 August 2008