Not Chemically Reactive

These materials are nonflammable.

These materials are not reactive unless under severe conditions or catalysis.

These materials tend to be relatively non-toxic.

These substances undergo chemical reactions only under relatively severe circumstances and are considered non-reactive under typical, ambient conditions. They are resistant to ignition, although they may become flammable at very high temperatures. They may be resistant to oxidation and reduction, except in the most severe conditions. These materials may be nontoxic. Gaseous materials in this group can act as asphyxiants.

Argon, carbon dioxide, helium, krypton, neon, nitrogen, sulfur hexafluoride, xenon.