IMDG Class 2 — gases, divided into 2.1 flammable gases (e.g. LPG, hydrogen, ethylene), 2.2 non-flammable non-toxic gases (e.g. CO2, nitrogen, oxygen), and 2.3 toxic gases (e.g. ammonia, chlorine in cylinder form). Class 2 in packaged form covers cylinders, IBCs, and small bulk packages; bulk gas cargoes are governed by the IGC Code instead of the IMDG Code. Stowage and segregation requirements vary by sub-division — for example, flammable gases must be segregated by 'separated from' or greater from oxidisers in Class 5.1.