Idaho State University Idaho State University Home PageISU Site Feedback FormISU Web Site SearchISU Website Index
Radiation Safety Training Module
Radiation Safety Training
Study Guide
ISU Technical Safety Office, Campus Box 8106
Pocatello, ID 83209
(208) 282-2311/2310

Quick Navigation

How to use this training


Acronym List


Contact TSO with questions


Radiation Safety Trng in .doc

Radiation Safety Trng in .pdf

Radiographic Sci Trng in .doc

Radiographic Sci Trng in .pdf

Alpha radiation

Alpha particles are the largest particles emitted from the nucleus of an atom.  Because of their relatively low velocity and large charge, chances are that soon after alpha particles are emitted they will quickly interact with an atom and lose their energy.  Alpha particles travel only a few centimeters in the air.  A piece of paper, normal work clothes, or the dead layer of skin on a human body can stop an alpha particle.  Because of their high energy, alpha particles can deposit a significant internal dose if inhaled or ingested.

Beta radiation

Beta particles are much smaller in mass than alpha particles and are less likely to collide with surrounding atoms. Therefore, they can travel much farther than alpha particles (up to several meters in air) and can penetrate some materials, including human tissue.  Certain materials can stop beta particles, such as a thin piece of metal or a few centimeters of wood, plastic, or glass.  Beta radiation presents a health hazard to the skin of the entire body, the eyes, and the internal organs if ingested or inhaled.

Gamma radiation

Gamma radiation is by far the most penetrating of the three common types of radiation (alpha, beta, gamma). Gamma rays have no mass or charge and are considered to be pure energy.  They can travel great distances and have the ability to pass through the human body and interact with living cells.  Lead, concrete, and other dense materials are used to attenuate (not to stop) gamma rays.

X-ray radiation

X-rays differ from gamma radiation only in their origin and the fact that they tend to be less energetic. Whereas gamma radiation originates in the nucleus of an atom, x-rays are generated by the shell transition of orbital electrons. They are also formed from the deceleration of electrons interacting with matter (this is known as bremsstrahlung).

Neutron radiation

In the past, neutron radiation normally was found only in the immediate vicinity of a nuclear reactor or nuclear weapons burst.  Today we are seeing more industrial use of neutron-emitting radionuclides.  Neutron-emitting radionuclides are being used in some specialized radiographic procedures, in well logging and soil moisture analysis. If accelerator energy is above 8 MeV, neutrons may be an important component of the radiation generated.
Neutron radiation is extremely difficult to detect.  Because neutron radiation is extremely penetrating, protecting workers is equally difficult.  Effective shielding for neutron radiation usually involves a material that has a high hydrogen atom concentration.  Such shielding might employ several feet of soil, paraffin (materials saturated with hydrogen atoms), or concrete.

Page: 5 of 23

This web based training was developed for use within Idaho State University.  It is intended for use by, and applies to ISU employees, staff, visitors, and students.  If this web site or any part of it is used elsewhere, neither its authors nor the University accept responsibility for its contents.  This information may NOT be used for commercial development or profit.