Basic Level Pre-Course Reading

Chapter 3
CBRN Assessment and Incident Recognition
3.2.3 Radiological/Nuclear Agents (Materials)
Radiation can be divided into two general categories: ionizing and nonionizing.
Non-ionizing Radiation is radiation such as Ultraviolet (UV) rays, microwaves,
lasers, and electromagnetic fields (EMFs) from electric power lines. Although
there are some health hazards associated with certain types and levels of nonionizing
radiation, the hazards are generally small.
Ionizing Radiation is radiation that may cause damage to the human body by
interacting with cells. It is this type of radiation that is dealt with in this course
and unless otherwise specified, references to “radiation” should be taken to
mean ionizing radiation. There are four major types of ionizing radiation.
• Alpha Particles are large atomic particles. They have little external
penetrating power, but can be harmful if alpha particle emitting radioactive
material enters the respiratory tract, is swallowed or enters through an open
wound. A typical alpha particle will travel no more than a few centimetres in
air and can be stopped by the outer layer of skin or a sheet of paper.
• Beta Particles are small atomic particles (electrons) that are fast moving
and have limited penetrating ability. They can be harmful if beta particles
emitting radioactive material enters the respiratory tract, is swallowed or
enters through an open wound. A typical beta particle can travel up to
several metres in the air and is stopped by skin, thin layers of wood or
plastic.
• Gamma Radiation and X-Rays are electromagnetic waves. Gamma
radiation and X-Rays are capable of penetrating all parts of the body and
can actually pass right through the body. These “waves” can travel several
metres in air and may be shielded by using concrete, steel, lead, or other
dense materials.
• Neutrons are particles that have been emitted from an atom’s nucleus and
are capable of penetrating all parts of the body. They are normally
associated with the operation of nuclear power plants and nuclear weapons.
Neutrons can travel long distances and may be shielded by using materials
such as wax, water, or concrete.
Radiological or radioactive materials emit ionizing radiation. Ionizing radiation is
energy in the form of electromagnetic waves (like x-rays) or sub-atomic particles.
This type of radiation cannot be seen, heard, felt, smelled, or tasted.
Radiation is everywhere in the natural environment. It comes from the sun, outer
space, soil and rocks, the air, and even from within the body. Everyone is
exposed to this natural “background” radiation every day.
CBRN First Responder Training Program
24
Basic Level Course