Radiological Fundamentals Flashcards
What are the 3 basic particles of an atom?
Proton, Neutron, Electron
Atomic number = number of ____ in nucleus.
Protons
Elements w/ atomic numbers of 83 or higher (bismuth & above) are inherently unstable and undergo _______ ________.
radioactive decay
Atoms that have the same number of protons but different number of ____ are called isotopes.
neutrons
If the number of protons change, the _____ changes.
element
Atoms or groups of atoms that have a net positive or negative electrical charge are called ____.
ion/s
Isotopes have the same chemical properties, but their ______ properties can be very different.
nuclear
Common notation describing isotopes is to list the atomic symbol for an element followed by its _____ number.
mass (Pu-239)
The mass number is the sum of ____ & ____.
protons & neutrons
Tritium has 1 proton & 2 neutrons - how is it denoted?
H-3
The particle(s) and/or energy released as the atom tries to become stable is called ______.
radiation
When an atom or other body changes from a higher energy state to a lower one, it emits energy in the form of waves or moving _____ _____ (i.e., radiation).
subatomic particles
Unstable atoms are known as _____ atoms, such as Carbon-14 which has 6 protons and ___ neutrons.
radioactive / 8
Radioactivity is the property of certain _____ or _____ to spontaneously emit radiation.
nuclides or isotopes
Radiation is particles or energy that can…
Come to & through you
Contamination is radioactive material in any unwanted place that can…
get on & inside you
dpm = disintegrations per ______
minute
dps = disintegrations per _____
second
Radioactivity is measured by the ______ of disintegrations radioactive material undergoes in a certain period of time.
number / amount
1 Curie = 2.22 E12 ___
dpm
1 Curie = 3.7 E10 ___
dps
In order to measure the radioactivity from contamination, we use instruments that indicate the number of times the radiation reacts w/ instrument over a period of time (usually 1 min) and is identified as ____ per minute or ____.
counts / cpm
A correction factor (cf) is applied to the counts per minute (cpm) to factor in any radiation the instrument did not detect and then converts the counts to ____.
dpm
CPM x __ = DPM
CF (correction factor)
To help measure the amount of contamination (ex. how much radioactive dust is on a given area), it is necessary to measure (survey) the contamination. We monitor a standard
area of about __ inches by __ inches or ___ square centimeters.
4 x 4 / 100
When documenting the amount of contamination measured, it is reported as dpm/___cm2.
dpm per 100 cm squared
If contamination is measured in the air or water, it is reported per unit of ____ such as ml, qt, g, lbs, etc.
volume
Ionization is the PROCESS of removing _____ from an atom.
electrons
______ radiation is energy (particles or rays) emitted from radioactive atoms that can cause ionization.
Ionizing
Some devices that emit ionizing radiation include…?
X-ray machines, accelerators, & fluoroscopes
What are the 4 basic types of ionizing radiation observed in the nuclear industry?
Alpha particles, beta particles, gamma/x-rays, & neutron particles
True or False: Exposure to ionizing radiation, w/o exposure to unconfined radioactive materials, will NOT result in contamination of the worker.
True
If radiation has enough energy to remove an electron from the atom, it is called _____ radiation and may be harmful to all life.
ionizing
What type of radiation does NOT have enough energy to ionize an atom?
non-ionizing (electromagnetic)
What are some examples of non-ionizing radiation?
Radar waves, microwaves, & visible light
Of the 4 types of ionizing radiation, which one has the largest mass?
alpha particles
Alpha particles have a (+) charge because they have 2 protons and no _____.
electrons
Alpha particle’s (++) charge strips electrons (-) from nearby atoms as it passes through the material, thus ____ these atoms.
ionizing
Due to alpha particles size and high charge, their range in air is about __ to __ _____.
1-2 inches
Alpha particles can sometimes be hard to detect because they are so easily _____.
shielded
Alpha radiation sources at the Hanford site are usually facilities that processed ____ for weapons or are storing that ____.
plutonium / waste
Are beta particles positively or negatively charged? What is their relative mass?
Both charges (+1 or -1) / small
Positively charged beta particles are called ____ and have a charge of +__.
positrons / 1
Negatively charged beta particles are physically identical to an _______.
electron
The Beta particle can cause ionization due to the repulsive force between the beta particle (-) and the electron (-). When a beta particle encounters an atom, the beta particle _____ the electron out of the atom’s orbit, thus ionizing the atom.
pushes
The range of a beta particle’s penetrating ability depends on the _____ of the beta particle. Does tritium (H-3) or strontium-90 (Sr-90) have a bigger range?
energy / Sr-90
If ingested or inhaled, a _____ emitter can be an internal hazard when source of radiation is in close contact w/ body tissue & can deposit energy in a small volume of living body tissue. Externally, this particle is potentially hazardous to the skin and ____ lens.
beta / eye
This type of ____-emitting isotope is found at most nuclear facilities/laboratories on the Hanford Site because it is created in abundance during the fission process of an operating nuclear reactor.
Beta
___ ___ and ____ radiation are electromagnetic waves (photons). They have a neutral (0) electrical charge. Gamma radiation is a ray, not a particle, and thus has no ___.
Gamma rays & X-ray / mass
_______ particles are neutrons that have been released from the nucleus of an atom. They have ____ charge and are approximately one quarter the mass of an alpha particle.
Neutrons / zero or neutral
Called “secondary ______”, an interaction can occur as the result of a collision between a neutron & a nucleus. The nucleus recoils due to the energy imparted by the neutron &
ionizes other atoms.
ionization
Because of the lack of an ____ ____, neutrons have a relatively high penetrating capability & are more difficult to shield. Neutrons can easily
travel several ____ feet in air.
electrical charge / hundred
Neutrons are most effectively stopped/shielded by using materials w/ a high ____ content, such as water, concrete, ____, paraffin or ____.
Hydrogen / plastic / oil
Sources of neutron radiation on the HS are found at facilities that contain ____ & certain ____ isotopes or where ____ fuel is stored.
plutonium / uranium / spent
A type of radiation dose unit pertaining to gamma/x-rays only, ______, is a unit for measuring external exposure - energy deposited by radiation in air.
roentgen (R)
RAD (Radiation Absorbed Dose) is a unit for measuring the amount of absorbed dose in ____ material.
any
What unit is used to measure the amount of biological damage to the human body from radiation?
REM (Roentgen Equivalent Man)
The millirem (mrem) is 1/____ of a rem.
1000
Radiation ____ ____ are used as a correction factor to reflect relative amount of biological damage caused by same amount of energy deposited in cells by different types of ionizing radiation.
Weighting Factors
REM = RAD x ___
WR
The radiation weighting factors (WR) for alpha = 20, beta = 1, gamma = ___, and neutron = (what range?).
1 / 5-20
Radiation / Time = ____ ____
Dose Rate
If 1 rem = 1000 mrem, 2.5 rem is how many mrem?
2500 (move decimal 3 places to the right)
If 1000 mrem = 1 rem, 4500 mrem is how many rem?
4.5 (move decimal 3 places to left)
