Although NBC agents differ substantially, in broad terms they present four main types of hazard:

• Contact
• Inhalation
• Injection
• Ingestion
  
  

Radiological agents present a significant additional hazard resulting from the radiation they emit.

Chemical, Biological and Radiological Hazards

Contact:
Chemical and biological hazards are created by agents in solid, liquid or vapour form that can be absorbed into the skin or through the eyes. Radiation can be absorbed through the skin or when in contact with the skin.

Inhalation:
Chemical and biological hazards are created by vapours, aerosols or contaminated dust inhaled into the lungs. Radiation particles are inhaled into the lungs providing a direct dose of radiation which can also form concentrations in the bones and thyroid.

Injection:
Chemical and biological hazards are created by direct injection into a vein or artery, or an agent moving into the blood stream from an injected area. Radiation can be injected through open wounds or on contaminated foreign bodies such as shrapnel.

Injestion:
Chemical and biological can be ingested into the digestive system. Radiation can be carried into the body via food and drink or from contaminated hands when they eat.