6.1
Poisonous materials are found in DOT division 6.1.
Division 5.1 contains oxidizers.
Poisonous gas is Division 2.3 in the DOT hazardous materials classification system.
In the US Department of Transportation Hazard Classification, and in all other such regulations around the world, Hazard Class 6 is for Poisonous Material. Hazard Class 6 contains Divisions: 6.1 - poisonous materials 6.2 - infectious substances
DOT class 6 division 1 materials consist of poisonous materials.
Division 2.3 is for poisonous gases.
DOT Class 2, Division 1 (more properly called Division 2.1) is for flammable gases.
Examples of Division 2.1 materials (flammable gases) include:acetylenediboraneRefrigerant Gas R32EthaneHydrogen, compressed
DOT class 6 includes:Division 6.1 - Poisonous materialsDivision 6.2 - Infectious substanceDOT Class 6 materials are:Division 6.1 - Poisonous materials Division 6.2 - Infectious substance
Class 2 division 1, more properly called division 2.1, is for flammable gasses.
For transportation purposes, elemental arsenic and many - but not all - of its compounds are in Hazard division 6.1 - poisonous materials.
"Non-flammable compressed gas" is the formal terminology. This class/division includes carbon dioxide (co2) cylinders, air tanks, and many industrial gasses described as "inert". Flammable gasses/aerosols, and toxic gasses/aerosols are also in class 2, but different divisions (2.1, and 2.3 respectively)