The chemical described above belongs to CLASS 1 EXPLOSIVES of DOT hazardous material classification. An hazardous substance is any substance which can cause adverse effects in humans when exposed to it. These substances are divided into different categories based on the way they react in different situations. It is mandatory that you aware of the kind of chemical you are working with when you are in the laboratory in order to take appropriate precautionary steps.
Because it is an asphyxiant.
