Pyrophoric class 7 materials

Pyrophoric and other spontaneously combustible substances will generally be identified as such on their product literature, material safety data sheets (MSDSs), or International Chemical Safety Cards (ICSCs). If transported, these substances should be identified as DOT/UN Hazard Class 4.2 materials for shipping purposes and labeled as spontaneously combustible. For pyrophoric substances, the NFPA 704 diamond for container or vessel labeling has a red (top) quadrant with a rating of 4, indicating the highest severity of flammability hazard (NFPA 704, 2001). Note that pyrophoric materials often exhibit one or more other reactivity hazards as well, such as water reactivity. 

Is any substance identified as spontaneously combustible YES Sodium hydrosulfite is DOT/UN Hazard Class 4.2, Spontaneously Combustible Material finely divided aluminum powder is pyrophoric without oxide coating... 

Hazard Class 4 - Division 4.2. Spontaneously Combustible Materials (These include pyrophoric materials and self-heating materials) ... 

Class D fires involve combustible metals, such as magnesium, titanium, potassium and sodium as well as pyrophoric organometallic reagents such as alkyllithiums, Grignards and diethylzinc. These materials burn at high temperatures and will react violently with water, air, and/or other chemicals. Handle with care ... 

Hazard. Hazard is an inherent property or ability of a substance to cause an adverse effect or event. Classes of hazards include physical hazards (e.g., compressed gases, explosives, flammables, organic peroxides, pyrophorics, unstable and water-reactive materials) and health hazards (e.g., asphyxiants, irritants, systemic toxins, reproductive toxins, carcinogens). 

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