Radiation COPY Flashcards
One Curie is that quantity of a radioactive material that will have how many disintegrations in one second
37 billion
A unit of exposure to x or gamma rays
Roentgen
A roentgen is that amount of radiation that will produce in air a given electrical charge per_____of air
Kilogram
What is the unit of absorbed dose in any substance
Radiation absorbed dose (RAD)
What is the unit of dose equivalent for any type of ionizing radiation sorted by body tissue in terms of its biological effect
Roentgen equivalent man
The REM is defined as the dose in RAD multiplied by the appropriate _____
Quality factor
REM = RAD x QF
What was designed so that all branches of science could use a single set of interrelated measurement units
System Internationale (SI)
Known formerly as the Curie this unit is used to measure radioactivity. It is the quantity of a radioactive material that will have one disintegration in one second
Becquerel
Formerly the RAD it is the unit used to measure absorbed dose for any type of radiation and any material. Equal to 100 RAD
Gray
Formerly the REM it relates the absorbed dose in human tissue to the effective biological damage of radiation. it is the equivalent to 100 REM
The sievert.
Primarily of galactic origin consisting of high-energy protons helium ions electrons, and photons. Interaction with an atmosphere by these particles produces most of the observed cosmic radios
Cosmic radiation
The intensity of cosmic radiation varies with what?
Latitude and elevation.
Higher elevations receive greater exposures.
Naturally occurring radioactive isotopes are a form of what type of radiation?
Terrestrial radiation
Terrestrial radiation consists of either isotopes produced by what
or
isotopes with _____ which have been present on earth since it’s creation
Interaction of cosmic rays
Long half lives
Direct terrestrial radiation dose varies with what
Location
What type of radiation occur is with building material such as concrete, brick, and stone, which contain quantities of uranium
Terrestrial radiation
Inhaled Radon 222, ingested potassium 40, carbon-14, etc are forms of what radiation
Natural radioactivity within the body, inhaled radioactivity
What are the most common type of man-made background radiation sources
Isotopic sources
They are intentionally produced by reading material with neutron beams from Excelerators IE cesium 137 which is used to check Radiac calibration
These sources make up the largest variety of radiation sources they can be classified as accelerators or reactors
Machine sources
What are the most common type of Excelerator source
X-ray machines
X-rays are high-energy photons that are how much more energetic than visible light?
1000 to 1,000,000
What is an example of a reactor type source
Nuclear reactor
A typical reactor may produce intensities up to how many RAD/Hr
1 billion
A person living near a nuclear reactor facility might receive an additional exposure of how many mR/yr
0.1 to 1.0 MR/yr
The average exposure from all backgrounds sources in the United States is approximately how many MR/year
203.3 MR/year
What is defined as the amount of time calculated to a sure that Personnel exposures do not exceed A predetermined level
Staytime
What is the best safety factor
Distance
If you double the distance from the source the intensity is reduced to _____of the original intensity
One quarter
What absorbs part or all of the various types of radiation
Shielding
X-ray shielding is based on the same mechanism as what
X-ray matter interaction
At a lower energies materials of high atomic number provide the attenuation at lower or higher barrier weight
Lower
All shield barrier material shall be a shored what what and what
Quality, uniformity, and permanency
In lead barriers joint should be in contact with how much of an overlap or twice the thickness, whichever is greater
One half inch overlap
What is the sole reason for concern about the effects of ionizing radiation
Interaction of radiation with matter particularly the human body
What is the term for any electromagnetic or particulate radiation capable of producing ion pairs in its passage through matter
Ionizing radiation
Ionizing radiation can be divided into two general categories what are they
Directly ionizing radiation and indirectly ionizing radiation
What type of radiation carries a charge and can deposit energy directly into an absorber
Directly ionizing radiation
What are the three major mechanisms which account for the energy deposition by charged particles in an absorber
Ionization, excitation, and bremsstrahlung
What occurs when an incident charged particle exerts a sufficient force of attraction or repulsion on the atomic orbital electron to completely remove one or more electrons from the atom. The positively charged atom from which the electron was removed and the removed electrons are referred to as what?
Ionization. Ion pair
What occurs when incident charged particles exert force on atoms to raise orbital electron to higher energy state but not enough force to completely remove them from their atom. the excited atom will emit photons when the electrons return to the ground state
Excitation
What is the x-ray radiation that may occur when charged particles interact with atomic nuclei of absorber Adams
Bremsstrahlung also known as “breaking radiation”
What type of radiation must first transfer energy to some charge particle in the disorder which in turn transfer some or all of that energy to the absorber
Indirectly ionizing radiation
What is a bundle if you were electromagnetic energy which has no mass or charge and is classified as indirectly ionizing radiation
Photon
What originates with particle consisting of two protons into neutrons are omitted from a radioactive atom
Alpha particles
What are the charge of alpha particles
+2
Alpha particles have a massive roughly how many times that of an electron
7000
Alpha particles are emitted from radioactive Adams with velocities of what
1/20th the speed of light
Alpha particles once inside the body will cause highly localized tissue damage near the point of origin due to what
Specific ionization
What originates when an electron is emitted from the nucleus of a radioactive Adam, along with unusual particle called the antineutrino
Beta particles
What are the charge of beta particles
-1
What is the mass of a beta particle
that of an electron
Beta particles have a wide range of energy from what to what
the average energy in the beta spectrum is what
Zero to maximum. The average energy in the Beta spectrum is 1/3 maximum
Beta radiation is more penetration that alpha particles because of what
High speed and lower electric charge
What type of radiation can be created because of the strong attractive force between the beta particle in the nucleus?
Bremsstrahlung x-rays
As the energy of the new John decreases the probability of absorption does what
Increases
What is a side effect of neutron absorption?
Unwanted gamma radiation
Materials of high atomic number or more likely to result in gamma ray mission from what
Neutron absorption
Scattering in what type of materials is the preferred method of shielding for example paraffin, water, plastics
Hydrogenous materials
What is the main factor that affects a cells sensitivity to radiation
Radiation absorbed dose (RAD)
What are the five categories of biological effects
Genetic Stochastic Non stochastic Teratogenic Somatic
Genetic biological effects occur in what type of cells
Reproductive cells
What is the effect for which the probability of an effect occurring rather than its severity, is a function of dose without threshold
Stochastic
What is the effects for which the severity of the fact varies with bills, and for which a threshold will occur
Non-stochastic
What is in effect occurring in the offspring as a result of an insult sustained in utero or while the mother is pregnant. This only occurs when the embryo is a radiated and not the mothers leg, arm, etc.
Teratogenic
What affects arise from damage to the cells in the body of an irradiated individual
Somatic
Somatic affects me be divided into two categories what are they?
Acute effects (short-term) and chronic effects (long-term)
What arise from large exposure is delivered in the period of a few hours or less and can result in observable symptoms and illnesses?
Acute effects
What are the three types of acute radiation syndromes?
Hematopoietic syndrome
Gastrointestinal syndrome
Central nervous system syndrome.
What syndrome occurs between 70 to 1000 RADs.
this damages blood forming organs organs symptoms of illness occur 1 to 2 days after exposure
Hematopoietic syndrome
Death me occurrence of individuals at how many rads
120 RADs
What occurs between 1000 to 10,000 RADs
Symptoms of illness occur within a few hours of exposure
death occurs within two weeks of exposure
Gastrointestinal syndrome
What occurs at 5000 RADS and above?
Symptoms of illness occur within minutes of exposure.
Death within three days of exposure
Central nervous system syndrome
Each of the acute radiation syndromes consist of four stages
(the time for the stages to occur shortens as exposure increases)
what are they?
Prodromal.
Latent.
Illness
Recovery
What are the effects which can show years after the original exposure these can come from acute or chronic exposures?
Chronic effects
What are the three examples of chronic effects
Cataracts. Shortened lifespan. Carcinogenic effects.
What is the primary causes of X radiography radiation accidents
Carelessness and lack of training
Three factors that lead to carelessness
Boredom fatigue and illness
What are three improper work procedures resulting in radiation accidents
Tube head left energized.
Radiation survey omitted/improperly done.
X-ray tube not secured from unauthorized.
All reports are submitted in detail on what form
NAVMED 6470/1 to BUMED (MED 21)
The NAVMED 6470/1 shall be submitted to BUMED via who?
Radiation health officer.
Instructions for completing the NAVMED 6470/1 are found where?
In the NAVMED P-5055 and on back of form
A whole body deuce in excess of the whole body exposure limit specified in chapter 4 of NAVMED P-5055 should be submitted in a report within how many days?
30 days
A whole body deuce of more than 5REM in a single incident constitutes what
Notification immediately by phone or immediate message and a report submitted within 24 hours.
A whole buddy dose of more than 25 REM constitutes what
Notification immediately by phone or immediate message and a detailed report within 15 days after exposure
What does RADIAC stand for
Radiation detection indication and computation meter
As I am as a snickers electrons released are collected by a positively charged anode resulting in what
Pulse of electrical current
The more radiation present the more iodization events which occur resulting in what
More current flow and a higher meter reading
And very low voltage is the ionize Adams simply read combine it with electrons resulting in no current flow. This is an example of what type of region
Recombination
Increasing the current a little allows each electron to be collected resulting in a low-voltage pulse. This is an example of what type of region
Ion chamber region
In the Geiger Mueller region voltages now so high that electrons which of been freed are accelerated, normally resulting in additional lyonization by collisions with other orbital electrons. This is called what
Gas multiplication or avalanche
Advantages of RADIACS
No need for highly stable voltage supply.
Flat energy response.
No dead time.
Fairly consistent/steady needle response
designed to measure again rays, x-rays, and beta particles
What are the disadvantages of RADIAC
Not very sensitive to very low energys.
Not rugged.
Pulses below 10 ^ -14th amps may look like tube noise
In accordance with manufacturers instructions and the RAD-010 the beta shield must be lowered for energies of how many kilovolts and below
120 KV
The Geiger Mueller is very energy dependent at low energy levels it has a flat response down to only how many KV
100
Chips 1, 2, and 3 are lithium 7 and are sensitive to what radiation
Photon and beat radiation
Chip 4 is lithium 4 which is sensitive to what
Photon, beta and neutron radiation
DT-702 card has additives of what elements
Magnesium copper and phosphorus
TLD’s are forwarded to radiological health lab how often
6 to 7 weeks
Storing TLDs above ____ cans cause a ___% reduction in sensitivity
115 F
25%
Accident dosimeters can detect neutron exposure is up to you how many rads and gamma exposures up to how many rads
Neutron 50,000
Gamma 10,000
Electronic personal dosimeter has an autoscaling range from ___ MR to ____ R
0.0 MR to 1600 R
(Alarm preset at 200 mrem and 200 mrem/hour
Unit to measure radioactivity
Curie
