RAD 201: Intro to Rad Protection

What Are X-rays?

 A form of ionizing radiation
 Ionizing radiation is radiation that produces positively and negatively charged particles (ions) when passing through matter.
 The production of these ions is the event that may cause injury in normal biologic tissue.

Consequences of Ionization in Human Cells

• creation of unstable atoms

• production of free electrons

• production of low-energy xr photons

Properties of X-rays

 Invisible
 Varying degree of penetration
 Electrically neutral
 Cannot be focused with a lens
 Travel in straight lines at the speed of light
 Produce charged particles and can cause fluorescence
 Will darken photographic film
 Wide range of energies

Control of “Radiant Energy”

 Use knowledge of radiation-induced hazards that have been gained over many years
 Employ effective methods to eliminate those hazards
 Control radiation produced from an x-ray tube and ensure safety during
all medical radiation procedures
 Limiting the energy deposited in living tissue by radiation can reduce the potential for adverse effects.

Erythema

redness of skin

Exposure (coulomb per kilogram [C/kg], or milliroentgen [mR])

amount of radiation produced in air when ionizing radiation is present.

Absorbed dose (milligray [mGy]):

the amount of energy that is deposited in a material per unit mass of the material.

Effective dose (millisievert [mSv]):

a quantity that is a measure of general harm in humans.

The three basic principles of radiation protection for pt AND tech

• time

• distance

• shielding

Background Equivalent Radiation Time (BERT

 A method that can be used to improve understanding and reduce fear and anxiety for the patient.
 Compares the amount of radiation received with natural background radiation received over a given period of time (see Table 1.1 in textbook)
 Based on an annual U.S. population exposure of approximately 3 mSv per year

Advantages of the BERT Method

 BERT does not imply radiation risk; it is simply a means for comparison.
 BERT emphasizes that radiation is an innate part of our environment.
 The answer given in terms of BERT is easy for the patient to comprehend