Details of these criteria can be found in the Controlled Products Regulations. Inert gases do not react chemically to any great extent. They do not burn or support combustion. Examples of this group are nitrogen, helium, neon, argon and krypton. The most common examples are hydrogen, methane and liquefied natural gas.
Many materials considered as non-combustible can burn in the presence of liquid oxygen.
Organic materials can react explosively with liquid oxygen. The hazards and handling precautions of liquid oxygen must therefore be considered separately from other cryogenic liquids. Cryogenic liquids are shipped and used in thermally insulated containers. These cryogenic liquid containers are specifically designed to withstand rapid temperature changes and extreme differences in temperature. They should have a loose fitting cap or plug that prevents air and moisture from entering, yet allows excess pressure to vent.