Ch. 9 Intro to Rad Protection Flashcards
What is the radiographers responsibility?
1) To ensure the patient receives the minimal dose to create a diagnostic quality image
2) To ensure the patient is not getting unnecessary dose
3) To use radiation safety habits to protect as needed
What type of radiation is produced in the x-ray tube during each exposure?
Ionizing radiation
What are the two main groups of ionizing radiation?
- Particulate radiation
- Electromagnetic radiation
What are alpha particles and their characteristics?
- Usually come from radioactive decay
- Very heavy (large mass
- Positive charge
- Travel only 5 cm in air
- Cannot penetrate skin
- Harmless externally, but cause great biological damage internally
What is a free radical in the context of ionizing radiation?
An unstable atom created when ionizing radiation knocks out an electron
Free radicals can potentially lead to biological responses such as mutations.
What is the responsibility of radiographers regarding radiation safety?
- Minimize patient dose
- Prevent unnecessary extra radiation exposure
- Use radiation safety habits
True or False: Ionizing radiation is always dangerous and has no benefits.
False
The benefits of ionizing radiation can outweigh the risks when used for disease detection.
Fill in the blank: Alpha particles usually come from _______.
[radioactive decay]
What are some examples of radiation safety habits?
- Gonadal shielding
- Thyroid shield
- Lead aprons
- Lead gloves
- Maintaining distance
Particulate radiation is produced by ________ _________.
Atomic collisions
What are beta particles?
Beta particles are lightweight particles that come from the nuclei of radioactive material and can cause biological harm.
They are lightweight and have a low mass
What is electromagnetic radiation?
Electromagnetic radiation includes forms such as X-rays and gamma rays, both of which can cause biological harm.
Where do X-rays originate from?
X-rays are man-made and originate from an X-ray tube.
Where do gamma rays originate from?
Gamma rays come from the nuclei of radioactive material.
What is the difference between X-rays and gamma rays?
The only difference is their source; both have very short wavelengths and can cause biological harm.
What are the biological effects of ionizing radiation?
Exposure can result in the development of a disease or pathology.
What factors must be considered in relation to radiation exposure?
Factors include:
* Amount of radiation received (dose)
* Time frame of radiation dose (rate)
* Type of radiation
* Person’s age
* Tissues and organs’ radiosensitivity.
How does the dose of radiation relate to risk?
Increased dose equals increased risk of biological effect.
What is the impact of the rate at which radiation is received?
The time frame of receiving a radiation dose affects biological effects; for example, 2 gy in 1 hour vs. 2 gy over 12 weeks.
What is the radiosensitivity of young individuals?
Young individuals (1-21 years) are radiosensitive due to immature stem cells.
What is the radiosensitivity of older individuals?
Very old individuals (75+) have increased radiosensitivity due to broken down cells.
Which tissues and organs are more radiosensitive?
Tissues with faster cell reproduction and immaturity are more radiosensitive, such as:
* Skin
* Bone marrow.
Which organs are more radioreistant?
More complex organs such as the brain, spinal cord, muscles, and liver are more radioreistant.
Fill in the blank: The faster the cells reproduce, the more _______ they are.
[radiosensitive]
What are the classifications of biological effects of radiation?
1) Somatic Effects 2) Genetic Effects
What are somatic effects?
Effects on all cells in the body other than sperm and egg cells
What are early effects of radiation exposure?
Biological symptoms that occur within minutes, hours, days, or weeks of exposure
Examples include immediate radiation sickness.
What are late effects of radiation exposure?
Biological symptoms that show up months or years later
These effects can include cancer or genetic mutations.
What are genetic effects?
Effects that occur to reproductive cells as a result of radiation exposure
These can cause mutations in future offspring.
What is a Geiger-Mueller Counter used for?
To detect the presence of radiation
It is most commonly used in nuclear medicine.
What is a scintillation device primarily used for?
Mainly found in gamma cameras, nuclear medicine, and CT
It detects and measures radiation.
What is an ionization chamber instrument also known as?
Cutie Pie
It is mainly used to measure radiation and test output of imaging equipment.
What are personal monitoring devices used for?
To estimate the amount of radiation exposure received
They are worn between the neck and waist, facing the radiation source.
What is an OSL dosimeter?
Optically Stimulated Luminescence dosimeter, common for detecting small doses of radiation
What are film badge dosimeters known for?
Inexpensive, durable, and good for record keeping
They are becoming obsolete.
What is a TLD dosimeter?
Thermoluminescent Dosimeter, common and accurate in low doses
It can come in ring badge form, particularly in nuclear medicine.
What is the annual occupational effective dose limit for radiation exposure?
50 mSv (50 millisievert) or 5 rem
This is the maximum dose a worker can receive annually.
When is personal monitoring device (PMD) required?
When workers are likely to receive 10% or more of the annual occupational effective dose
This ensures safety and compliance with radiation exposure regulations.
What is a Pocket Dosimeter?
A device used for immediate radiation readouts but lacks a permanent record
How does an Electronic Digital Dosimeter work?
It is similar to a jump drive and inputs data into a computer for software processing
Considered the new, expensive, and future of dosimeters
What are the three sources of natural radiation?
- Cosmic radiation
- Terrestrial radiation
- Internal radiation
Natural origin radiation is often referred to as ‘Background’ radiation
Name three man-made sources of radiation.
- X-rays
- Radiopharmaceuticals
- Consumer products
- Medical imaging
- Air travel
- Nuclear power plants
What percentage of radiation exposure is attributed to medical imaging from Computed Tomography?
24%
This includes various imaging techniques in healthcare
What percentage of radiation exposure comes from Occupational sources?
Less than 0.1%
Fill in the blank: The __________ source of radiation is from radioactive material in the ground.
[Terrestrial]
What is the percentage contribution of Consumer products to radiation exposure?
2%
This includes items like detectors, old TVs, and microwaves
True or False: Air travel is considered a source of cosmic radiation.
True
What percentage of radiation exposure is attributed to Industrial sources?
Less than 0.1%
What is the contribution of Nuclear Medicine to radiation exposure?
12%
Fill in the blank: __________ radiation can be ingested or inhaled.
[Internal]
What does SI stand for in the context of radiation units?
International System of Units
The SI units are used internationally and include standard measurements for various physical quantities.
What is the SI unit of exposure to radiation in air?
c/kg (Columb per kilogram)
The traditional unit is Roentgen (R)
What is Air Kerma?
Kinetic energy released in matter
Air Kerma is mainly used when testing equipment.
What is the SI unit for Absorbed Dose?
Gray (Gy)
The traditional unit is RAD (Radiation Absorbed Dose)
How is 1 Gy defined in terms of energy absorption?
1 joule of energy absorbed into one kg of tissue
What is Integral Dose?
The total amount of energy given into matter
It is calculated as the product of absorbed dose and the mass over which radiation is given.
What is the purpose of Equivalent Dose (EqD)?
Absorbed dose to the patient, radiation worker, or general public with the idea of factoring in the type of radiation and the different biological effect it may have on
What is the SI unit for Equivalent dose?
Sv (Sievert)
The traditional unit is REM (Radiation Equivalent Man)
What does Effective Dose (EfD) consider?
The absorbed does to the patient or radiation worker with the idea of factoring in the type of radiation received and the type of tissue being radiated
What is Activity (A) in the context of radiation?
The quantity of radioactivity
Activity measures how much radioactive material is present.
What is the SI unit for Activity?
Becquerel (Bq)
The Traditional unit is Ci (Curie)
Fill in the blank: The traditional unit for Absorbed Dose is _______.
RAD
True or False: The Effective Dose (EfD) does not consider the type of tissue being radiated.
False
Fill in the blank: The SI unit of Equivalent Dose is _______.
Sv
What are the two types of weighting factors used in radiation measurements?
- Wr (radiation weighing factor)
- Wt (tissue weighing factor)
What is the primary conclusion regarding x-ray exposure?
The diagnostic benefit outweighs the minimal risk resulting from x-ray exposure
Define ionizing radiation.
Any form of radiation that possesses energy capable of displacing atomic electron bonds and breaking the electron bonds that hold the molecules of matter together
What is the significance of understanding proper radiation protection practices?
To mitigate potential biological damage from the ionization process
Awareness of radiation risks is essential for safety.
List the two sources of ionizing radiation.
- Natural background radiation
- Man-made radiation
Understanding these sources helps in managing exposure.
What percentage of natural background radiation comes from Thoron and Radon?
37%
This is a significant portion of natural radiation exposure.
What are the components of man-made radiation exposure percentages?
- 24% = CT
- 12% = nuclear medicine
- 7% = interventional fluoroscopy
- 5% = conventional radiography
- 2% = consumer
- <0.1%= occupational
These figures illustrate the various contributions to man-made radiation exposure.
Differentiate between somatic and genetic biological effects of radiation.
- Somatic: Occurring to the individual exposed
- Genetic: Occurring in the descendants
Understanding these effects is crucial for evaluating risks.
What is the radiographer’s responsibility regarding radiation dose?
Ensure each patient receives the minimal dose of radiation necessary to produce a diagnostic image
This emphasizes patient safety in imaging procedures.
What are the SI units of measurement for exposure and dose in radiation?
- Exposure: C/kg
- Absorbed dose: Gy
- Equivalent dose: Sv
What are some measurement devices used in radiation protection?
- Geiger-Mueller counter
- Scintillation device
- Ionization chamber instrument
Name the personal monitoring devices (PMDs) used for radiation exposure.
- OSL
- Film badge
- TLD
- Pocket dosimeters