248, ch 1-3 quiz; 4-5 quiz & kahoot; 1-3 & 4-5 LA

Dose Area Product (DAP):

The sum total of air kerma over the exposed area of the patients surface.

description of protons:

- positively charged components of an Atom. - # of protons in the nucleus constitutes its atomic number (identifies element and where it is in the periodic table).

Equivalent Dose (EqD):

- quantity used for radiation protection purposes when exposed to various types of ionizing radiation. - attempts to numerically specify the differences in transferred energy (aka potential biologic harm) that are produced by different types of radiation. - EqD is the product of the average absorbed dose in a tissue and its associated radiation weighting factor. - Equivalent dose enables the calculation of the affective dose (EfD).

Total Effective Dose Equivalent (TEDE):

- system of units and quantities used to monitor workers. - TEDE is the sum of effective dose equivalent from external radiation and the committed effective dose equivalent (CEDE) from internal sources. - It is designed to take into account all possible causes of radiation exposure.

description of neutrons:

- the electrically neutral components of an Atom. - If 2 atoms have the same # of protons but different # neutrons in their nuclei, they are referred to as isotopes. - combinations of protons/neutrons leads to an unstable nucleus , then that combination is called a radioisotope.

Sievert (Sv):

- the product of the absorbed dose and the radiation weighting factor. - This unit is only used for radiation protection purposes; provides a common scale of biologic damage caused by equal absorbed of different radiation can be compared with the biologic damage caused by the same amount of x-radiation or gamma radiation. - In the traditional system, 100 rem equals 1 seivert.

All of the following are true of pocket ionization chambers except: - they are reasonable accurate and sensitive to radiation. - they are fairly inexpensive - they are compact and easy to carry. - they provide immediate exposure readouts.

- they are fairly inexpensive

What is the name of the campaign with the aim to lower the amount of radiation used in medically necessary imaging and eliminating unnecessary procedures?

Image wisely campaign

What type of radiation comes from planetary and extraplanetary sources?

natural background radiation

The Geiger-Muller (GM) survey meter is used for area monitoring in:

nuclear medicine facilities.

During routine procedures when an apron is not worn where is the dosimeter worn?

on the front of the body at collar level

what is particulate radiation?

particulate radiation is a form of radiation that includes Alpha particles (nuclei of helium), beta particles (electrons), neutrons, and protons that are ejected from Atoms at very high speeds.

1. What is the term for biologic damage to the body cause by exposure to ionizing radiation?

Somatic effects

what are the 2 types of electromagnetic radiation?

- ionizing - non-ionizing

The most common type of survey meter that uses an ionization chamber is called the "Cutie pie".

true

description of beat particles:

- 8000 x's lighter than Alpha and have only one unit of electrical charge (-1). - will not interact as strongly with their surroundings as Alpha does. -capable of penetrating biologic matter to a greater depth than Alpha with less ionization.

Collective Effective Dose (ColEfD):

- Designated for use in the description of a population or group exposed to different individual amounts of ionizing radiation. - It equals to the sum of all the doses times the number of individuals exposed and would be expressed in units such as person - Sv

description of Compton scattering interaction w/ matter:

- Important in diagnostic/therapeutic radiology. - the scattered X Ray photon produced results in a partial transfer of kinetic energy to that biologic Atom - the scattered photon now travels in a different direction, can become a hazard for techs. - when these scattered photons reached the IR, they can lower contrast of the image. - Because its energy dependence decreases much more slowly with increasing energy, it is very important even at therapeutic energies.

description of Photodisintegration interaction w/ matter:

- Important in therapeutic radiology. - incoming high energy photon collides with nucleus of an Atom and absorbs all the photons energy. - This energy excess in the nucleus creates instability that is usually alleviated by the emission of a neutron. - if sufficient energy is absorbed by the nucleus, other types of emissions are possible like a proton, or proton-neutron combination, or even an Alpha particle.

description of pair production interaction w/ matter:

- Important in therapeutic radiology. - occurs when incoming X Ray photons with energy of at least 1.022 MeV interact with the nucleus of an Atom. - The end result is annihilation of a positron and an electron with their masses are converted into energy, each moving in the opposite direction.

description of coherent scattering interaction w/ matter:

- Not important. - When interacts with human tissue, it does not lose kinetic energy. The emitted photon just changes directions by 20 degrees or less. -No ionization occurs.

description of photoelectric absorption interaction w/ matter:

- Only important in diagnostic radiology. - interaction is responsible for both patient's dose AND contrast in the image. - the total energy of the incident photon is completely absorbed as it interacts with an inner shell ē of biologic tissue from orbit. The new ejected photoelectron has kinetic energy and can ionize other atoms until its energy is spent. - After losing an ē, the original ionized Atom is unstable in attempts to re stabilize. This occurs as an ē from a higher shell drops to fill the vacancy in the inner shell by releasing energy as a characteristic photon. -This cascading effect of ē dropping down to fill shell vacancies continues until the original Atom regains stability.

What are the 3 cardinal rules of radiation protection?

- Time - Distance - Shielding

what are some examples of non-ionizing electromagnetic radiation?

- Visible light - Infrared rays - Microwaves - Radio waves - UV radiation with energy less than 10eV

Reports that may be generated by a digital ionization dosimeter include all of the following except: - Who Has Not Read Their Device. - History Detail Report. - X-ray Equipment QC Reports. - Radiation Exposure Summary Report.

- X-ray Equipment QC Reports.

what are some examples of ionizing electromagnetic radiation?

- X-rays - Gamma rays - UV radiation greater than 10eV

All of the following are types of gas-filled radiation field instruments except: - GM survey meter - digital ionization dosimeter - Cutie pie - proportional counter

- digital ionization dosimeter

Absorbed Dose (D):

- energy per unit mass absorbed by an object (body). This absorbed energy is responsible for biologic damage. - The gray (Gy) is the SI unit of this radiation quantity.

All of the following are true of a control monitor except: - it should have similar reading to all other dosimeters in a batch. - it should be kept in a radiation free area. - it should have a reading of zero. - it serves as a comparison for all other dosimeters in a batch.

- it should have similar reading to all other dosimeters in a batch.

description of an alpha particles:

- much less penetrating because they lose energy quickly as they travel a short distance. -considered virtually harmless as an external source of radiation, however, as an internal source the reverse is true.

Threshold dose:

- point which a response/reaction to increasing stimuli first occurs - with reference to inonizing radiation, this means below a certain radiation level/dose, no biologic effects are observed.

Personnel dosimetry is required when workers are at risk of what percent of the annual occupational limit?

10%

What are characteristic x-rays also known as?

Fluorescent radiation

What is the name of the interaction that occurs at more than 10 MeV of energy?

Photodisintegration

Which of the following dosimeters is most sensitive to radiation? Pocket Ionization Chamber Film badge TLD OSL

Pocket Ionization Chamber

1. Which is the most sensitive type of personnel dosimeter?

Pocket ionization chamber (pocket dosimeter).

What is the term for kinetic energy that passes from one location to another?

Radiation

what is electromagnetic radiation?

Radiation composed of interacting, varying electric/magnetic fields that travel through space at the speed of light.

1. What is the term for reddening of the skin caused by exposure to radiation?

Radiodermatitis

Undesirable, additional exposure to the image receptor is called _____________?

Radiographic fog

What is the term for an element with unstable nucleus that emits one or more forms of ionizing radiation to achieve greater stability?

Radioisotopes

Radiodermatitis:

Redning of the skin caused by exposure to inonizing radiation.

Describe the requirements for personnel monitoring:

Required when workers are likely to risk receiving 10% or more of the annual occupational EfD limit (50 mSv) in any single year.

Air kerma (Gya):

SI quanity thats used to express radiation energy transferred to a point (the body). - Air kerma is kenetic energy released in a unit mass (kg) or air and is expressed in metric units of joules per kilogram (J/kg).

Gray (Gy):

SI unit of absorbed dose and air kerma. One Gy equals an energy absorbption of 1 joule (J) per kilogram (kg) of matter in the irradiated object. In the tradiational system 100 rad equals 1 Gy.

Which of the following statements is true? Select one: a. 100 rem = 1 centisievert b. 10 rem = 1 centisievert c. 1 rem = 1 centisievert d. 0.1 rem = 1 centisievert

c. 1 rem = 1 centisievert

Which of the following should be part of the employment record of all radiation workers? Select one: a. A list of all fluoroscopic procedures performed daily b. A list of all radiographic procedures performed daily c. A record of exposure recorded by personnel dosimeters d. A report of all procedures performed when "on call" after regular hours

c. A record of exposure recorded by personnel dosimeters

What is the maximum period of time that a thermoluminescent dosimeter (TLD) may be worn as a personnel dosimeter?

d. 3 months

The effective atomic number (Zeff) of lithium fluoride (LiF) is equal to:

d. 8.2

What are the 4 types of particulate radiation?

- Alpha particles - Beta particles - Neutrons - Protons

Cosmic radiation occurs in what 2 forms?

A: solar and galactic

What is the maximum length of time that an OSL dosimeter can be worn?

1 year

Annihilation radiation is used in which modality?

A: positron emission tomography (PET)

All of the following are true of digital ionization dosimeters except: - they can only be used once. - they are small and similar to a flash drive. - they provide immediate exposure readouts. - they have built-in memory chips that store user and facility info.

- they can only be used once.

Disadvantages of the Cutie pie include all of the following except: - they cannot be used to accurately measure diagnostic procedures. - if not warmed up the meter will drift on its most sensitive scale. - they have a delicate detector. - they can read, x-ray, gamma-ray and beta radiation.

- they can read, x-ray, gamma-ray and beta radiation.

Exposure (X):

- total electric charge of one sign, either all (+) or all (-), per unit mass that xray and gama ray photons with energies up to 3 MeV generate in dry air at standard temperature and pressure; - amount of ionizing radiation that may strike and object (the body) when in the vicinity of a radiation source. - In the SI unit system it can be measured in coulombs per kilogram (C/kg).

Effective Dose (EfD):

- used for radiation protection purposes to provide a measure of overall risk of exposure from ionizing radiation. - effective dose takes into account all types of ionizing radiation to various irradiated organs/tissues in the human body. - EfD takes into account the chance/risk for each body part to develop radiation induced cancer/genetic damage.

Define the term "diagnostic efficacy" and explain how this concept is used for radiation protection.

- when a diagnostic study accurately reveals the presence/absence of a disease in a patient. - maximized when images are produced with the least radiation to the patient.

Tolerance dose:

A radiation dose to which workers could be continuously subjected without any effects, such as erythema.

List the 8 fundamental properties of x-rays.

1. X-rays are invisible. 2. Can in vary in penetration in normal tissue ranging from superficial to deep (dependent on energy) 3. Are not deflected from their paths by electric/magnetic fields (electrically neutral). 4. Visible light may be focused with a lens, x-rays cannot be. 5. X-rays travel in straight lines at the speed of light until they interact with an atom. 6. x-rays produce charged particles by interacting with atoms of matter and cause an emission of light called "fluorescence" in some crystals. 7. X-rays darken film, with a degree of darkening on the film being related with intensity of rays. 8. Xray beams have a wide range of energies (normally heterogeneous not monoenergetic).

Identify the 3 advantages of BERT.

1. does not imply risk; it is a means for comparison. 2. emphasizes radiation a part of our environment. 3. provides an answer that is easy for the patient to comprehend.

The maximum length of time that a TLD can be used is

3 months

What is the annual occupational EfD limit?

50 mSv (5 rem)

Advantages of the BERT method are: 1. it does not simply imply radiation risk; it is simply a means for comparison. 2. it emphasizes that radiation is an innate part of our environment. 3. the answer given in terms of BERT is easy for the patient to comprehend.

A: 1, 2, and 3

Which pf the following statements below are true? 1. it appears that no safe dose level exists for radiation-induced malignant disease. 2. the ALARA principle establishes a dose level for radiation-induced malignancy. 3. the BERT method establishes a dose level for radiation-induced malignancy. 4. the NEXT program and reference values establish a dose level for radiation-induced malignancy.

A: 1. it appears that no safe dose level exists for radiation-induced malignant disease.

According to the environmental protection agency (EPA), radon levels in homes should not exceed what level?

A: 4 pCi/L

Coherent scattering is most likely to occur ______ even though some of this scattering occurs throughout the diagnostic range and may result in small amounts of radiographic fog.

A: below 10 keV

Which of the following helps shield the global population from exposure to essentially all high-energy, bombarding cosmic rays?

A: earth's atmosphere and magnetic field

Which pf the following provides the basis for determining whether an imaging procedure or practice is justified?

A: efficacy

The probability of occurrence of photoelectric absorption ____ as the energy of the incident photon decreases and the atomic number of the irradiated atoms ____.

A: increases markedly; increases

Which of the following interactions between photons and matter involves a matter-antimatter annihilation reaction?

A: pair production

In the electromagnetic spectrum, higher frequencies are associated with:

A: shorter wavelengths and higher energies

Which of the following is the intention behind the ALARA concept?

A: to keep radiation exposure and consequent dose at the lowest possible level.

Electromagnetic radiation can travel through space in the form of a wave but can also interact with matter as a particle of energy. This dual nature is referred to as:

A: wave-particle duality

Which of the following terms refers to the radiation that occurs when an electron drops down from an outer orbit to fill a vacancy in an inner orbit of the parent atom?

A; characteristic radiation

The amount of kinetic energy transferred to electrons per unit mass that is absorbed in material, is which radiation quantity?

Absorbed dose

1. What type of sensing material is used in an OSL dosimeter?

Aluminum oxide detector

What type of radiation is used in the nuclear medicine modality of positron emission tomography (PET) imaging?

Annihilation radiation

What is the term for a way that radiographers can improve understanding and reduce patient fears and anxiety about radiation doses?

BERT = Background equivalent radiation time

Who was the first American fatality as a result of radiation exposure?

Clarence Madison Dally

Who was the first American radiation worker to die from radiation-induced cancer in October of 1904?

Clarence Madison Dally

1. The dosimeter badge that serves as the basis of comparison for all badges in a batch is known by what term?

Control monitor

1. What is the basic unit of electrical charge?

Coulombs

1. What is the sensing material in a TLD badge?

Crystalline form of lithium fluoride

The degree to which the diagnostic study accurately reveals the presence or absence of disease in a patient, is the definition of what term?

Diagnostic efficacy

1. What is the term for the entire amount of energy delivered to the patient by the x-ray beam?

Dose Area Product (DAP)

What is the term for a composite Z value for which multiple chemical elements comprise the material?

Effective atomic number (Zeff)

The sensing material in a TLD is

Lithium fluoride (LiF)

1. The largest dose of ionizing radiation that an occupationally exposed person was permitted within a certain period of time, that was not expected to result in major adverse biologic effects, is the definition of what term?

Max Permissible Dose (MPD)

Which of the following is not one of the filters found in the OSL dosimeter? Tin (Sn) Copper (Cu) Aluminum (Al) Molybdenum (Mo)

Molybdenum (Mo)

1. What new term is synonymous with the term ALARA (as low as reasonably achievable)?

ORP = Optimization for radiation protection

Which device is most commonly used for monitoring of occupational exposure?

OSL

Skin erythema dose:

The received quantity of radiation that causes diffused redness over an area of skin after irradiation.

Tissue kerma (Gyt):

The total kenetic energy released in a unit mass of tissue, given in units of joules per kilogram (J/kg).

1. A dosimeter worn at the collar level will provide approximate equivalent dose readings to which two, highly sensitive organs?

Thyroid and eyes

Where should a second monitor be worn during surgical procedures using x-rays?

Under the apron at waist level.

Among physicians, cancer deaths attributed to x-ray exposure were reported as early as:

a. 1910.

Which of the following is not true about field survey instruments? Select one: a. They are all equally sensitive in the detection of ionizing radiation. b. They detect the presence of radiation and, when properly calibrated, give a reasonable accurate measure of the exposure. c. They are durable enough to withstand normal use. d. They are reliable.

a. They are all equally sensitive in the detection of ionizing radiation.

Which of the following are types of ionizing radiation that produce virtually the same biologic effect for equal absorbed doses in body tissue? Select one: a. X-rays, beta particles, and gamma rays b. Alpha particles, beta particles, and gamma rays c. X-rays, neutrons, and gamma rays d. X-rays, alpha particles, and fast neutrons

a. X-rays, beta particles, and gamma rays

In the diagnostic radiology energy range from 23 to 150 kVp (which includes mammography), which of the following tissues possesses the greatest ability to absorb radiant energy through the process of photoelectric absorption? Select one: a. Air b. Bone c. Fat d. Muscle

b. Bone

Which of the following devices contains an aluminum oxide detector? Select one: a. Film badge dosimeter b. Optically stimulated luminescence dosimeter c. Pocket ionization chamber d. Thermoluminescent dosimeter

b. Optically stimulated luminescence dosimeter

A dosimeter can protect the worker from exposure because it is capable of detecting & measuring the amount of radiation.

false

Pocket ionization chambers are commonly used monitors in diagnostic imaging.

false

The OSL dosimeter can be greatly affected by heat, moisture and pressure.

false

Maximum permissible dose (MPD):

the max dose equivalent of ionizing radiation that workers could absorb in a specific time period without sustaining harm.

A dosimeter only records exposure in the area the device is worn.

true

A record of radiation exposure is a part of the employment record and must be given to the employees when changing jobs.

true

Heath care facilities will issue dosimeters when personnel could receive 1% of the annual occupational limit.

true

In its audio mode the GM survey meter can be used to scan radiation barriers for defects.

true