It is capable of detonation or explosive reaction if it is subjected to a strong initiating source or if heated under confinement.

It is readily capable of detonation or explosive decomposition or reaction at standard temperature and pressure.

It is a known forbidden substance or a class A or B explosive.

Toxicity:

It is a material that contains or degrades into toxic components in concentrations that pose a potential hazard to the environment or to the public health and that may be fatal to human in low doses.

HAZARDOUS WARNING MARKINGS AND LABELS

Specific hazards can be determined at a glance by referring to warning markings and labels that identify hazardous materials. Hazardous warning markings and labels are necessary to show clearly the hazardous nature of the contents of packages or containers at all stages of storage, handling, use, and disposal. When unit packages (marked packages that are part of a larger container) are removed from shipping containers, the continuity of the specific hazard warning must be preserved. This is normally done by applying the appropriate identifying hazardous label to the hazardous material container or package.

The Department of Transportation (DOT) labeling system, shown in figure 7-3, is a diamond-shaped symbol segmented into four parts. The upper three parts reflect hazards relative to health, fire, and reactivity. The lower part reflects the specific hazard that is peculiar to the material.

The four specific hazards that the labels are designed to illustrate areas follows:

Health Hazard - the ability of a material to either directly or indirectly cause temporary or permanent injury or incapacitation.

Fire Hazard - the ability of the material to burn when exposed to a heat source.

Reactivity Hazard - the ability of a material to release energy when in contact with water. This term can be defined as the tendency of a material, when in its pure state or as a commercially produced product, to vigorously polymerize, decompose, condense, or

Figure 7-3. - Hazardous code chart.