Radiation Protection / Radiobiology 2 Flashcards
Working habits and conditions of personnel can be assessed over a designated period of time. 3 examples =
Monthly
Quarterly
Yearly
What 3 work areas typically have higher readings?
Fluoro
Portables
Interventionals
Wear a monitor at collar to monitor ____ and ____
Thyroid
Eye dose
If 2 devices are worn, “hot” = _____ …. And “cold” = _____
Hot = on collar Cold = at waist under apron
Wear device at ______ to monitor thyroid and eye dose
Collar
True or false: Pregnant workers do not have to “declare” pregnancy to get an additional badge
False. They HAVE to declare pregnancy first then they will receive a second badge
______ or ______ badges should be worn if hands are frequently near primary beam
TLD
Finger
Nuclear Medicine Technologists should wear _____ or finger badges
TLD
True or false: HC facilities / education programs must maintain exposure records
True
Personnel monitors must be _____, _____, and _____.
Portable
Durable
Cost-efficient
Permanent record and can be re-read
Film badges
Come with a “control badge” for non-radiation area
Film badge
Newest, similar to film badge
Optically Stimulated Luminescence Dosimeters (OSL)
Uses Aluminum Oxide crystals that are stimulated by a laser to give off light that is read only once
Optically Stimulated Luminescence Dosimeter (OSL)
Looks like a pocket flashlight, can be read only once, not used much
Pocket Ionization chambers
Self-reading Pocket Ionization chambers are for instant ___________.
Dose reading
Non self-reading Pocket Ionization chambers require a …
Reading device
Uses Lithium Fluoride crystals that give off light when heated, read only once, responds most like human tissue
Thermoluminescent Dosimeter (TLD)
_________ and/or ________ reviews reports and councils employees if necessary
Radiation Safety Officer (RSO)
Health Physicist
Area monitoring done with radiation survey instruments must be _____ and _________
Durable
Easy to carry
Tube which indicates presence/absence of radiation
Geiger-Muller Tuber (GM Tube)
Gas filled survey instrument
Cutie Pie
RSO
Radiation Safety Officer
Erythema
Skin reddening
Epilation / alopecia
Hair loss
The higher the dose, the _____ the latent period
Shorter
Latent Period
Symptom-free period
Hematopoietic Syndrome
1-10 Gy (100-1,000 Rads)
Probable death within 6-8 weeks due to decrease in number of RBC, WBC, destroyed immune system
Hematopoietic Syndrome
GI syndrome
10-50 Gy (1,000-5,000 Rads)
Certain death within 3-10 days due to excessive diarrhea, vomiting, etc
GI Syndrome
CNS Syndrome
50+ Gy (5,000+ Rads)
Certain death within minutes to hours due to excessive cranial fluid
CNS Syndrome
Divisions of Acute Radiation Syndrome (3)
Hematopoietic
GI
CNS
Response stages of ARS (4)
Prodromal / initial stage
Latent period
Manifest illness
Recovery or death
Within hours»_space; nausea, vomiting
Prodromal or Initial Stage
About 1 week after Prodromal»_space; NO symptoms
Latent period
Full signs/symptoms appear
Manifest illness
In approx. 3 months from Prodromal Stage
Recovery or death
LD 50/30
Lethal dose that can kill 50% of the exposed population within 30 days
LD 50/30 range
3-4 Gy (300-400 Rads)
Rays of 10-20 kVp used to treat acne and ringworm
Grenz
German word for “boundary”
Grenz
Tabletop dose for routine fluoro cannot exceed
10 R/min
High-Level Control Fluoro (HLCF) cannot exceed
20 R/min
Temporary sterility may occur at gonadal dose of
2 Gy (200 Rads)
Permanent sterility may occur at gonadal dose of
5-6 Gy (500-600 Rads)
Whole body dose as low as _____ may cause a ,easer able hematologist depression
0.25 Gy (25 Rads)
Most radiosensitive cells in body
Lymphocytes
Least radioresitant cells in body
Lymphocytes
Least radioactive cells in body
Adult nerve cells
Most radioresitant cells in body
Adult nerve cells
Photomicrograph showing chromosomal “map”
Karotype
Cells are MOST radiosensitive during
Metaphase (“M”)
Indirect effect damage occurs ___ of the time (due to radiolysis of water)
95%
Direct effect damage occurs ___ of the time
5%
Dose-response relationship curves
Linear
Non-linear
Threshold
Non-threshold
_______ and _______ are plotted on linear, non-threshold curves (“no safe limit”)
Diagnostic
Leukemia
______ effects occur in the exposed individual
Somatic effects
________ effects are late somatic effects that can be directly related to the dose received
Deterministic
_______ effects are NOT likely to occur from diagnostic imaging procedures
Deterministic
Late somatic effects that do not have a threshold, occur in an arbitrary manner
Probabilistic
Late somatic effects have a severity that does not have a threshold
Probabilistic
Late somatic effects that occur in an arbitrary manner (no rhyme or reason)
Probabilistic
Late somatic effects at have a severity that does not depend on dose
Probabilistic
Late somatic effects that can occur after high or possibly low level exposures
Probabilistic
Extrapolation
Estimating the dose
Used by radiologists to establish dose-response curve for diagnostic exposures
Extrapolation
______ is the MOST important late stochastic somatic effect caused by exposure to ionizing radiation
Cancer
Mostly young women who suffered from bone cancer (radium chemically similar to calcium)
Radium watch dial painters
Early Uranium miners suffered from high incidences of ______ cancer
Lung
Infants treated for am enlarged thymus gland layer suffered from _____ cancer
Thyroid
Known places exposed to high levels of radiation include:
Hiroshima and Nagasaki (Japan 1945)
Chernobyl (Soviet Union 1986)
Genetic effects occur in
Offspring of exposed individual
2 examples of Genetic effects
Down’s Syndrome
Microcephaly
If both parents possess the point mutation it is called:
Dominant
If only one parents possess the point mutation it is called
Recessive (probably won’t be seen for several generations)
NCRP Report #___ and Publication #___ of ICRP are resources for EfD Limiting System
116
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Radiation Hormesis
Hypothesis that a small amount of radiation is safe
Group that implements US Radiation Protection Policies
NCRP
Group that controls manufacture and use of radioactive substances
NRC
Group that regulates design/manufacture of products used in radiation industry
FDA
States that have agreements with NRC to enforce radiation regulations through their health departments
Agreement States
Both state and NRC enforce regulations
Non-Agreement States
Oversees daily operation and develops safety programs
Radiation Safety Officer
Act passed to protect public from hazards of unnecessary radiation exposure from electronic products (TVs, microwaves, etc.)
1968 Radiation Control for Health and Safety Act
Act that requires establishment of minimal standards for accreditation of education programs
Consumer-Patient Radiation Health and Safety Act of 1981
Biological somatic effects that exhibit a threshold dose below which the effect does not normally occur
Nonstochastic effects
Biologic somatic effects above which severity of damage increases as dose increases
Nonstochastic
Nonthreshold, randomly occurring somatic changes in which chance of occurrence of effect rather than severity of effect is proportional to dose
Stochastic effects
Annual EfD for occupational exposure
50 mSv (5 Rem)
Cumulative EfD
Age in years x 10 mSv (1 Rem)
Annual dose limit for lens of eye
150 mSv (15 Rem)
Annual dose limit for skin, hands, feet
500 mSv (50 Rem)
Annual EfD for general public infrequent exposure
5 mSv (0.5 Rem)
Dose for 17 year old student
1 mSv (0.1 Rem)
Fetal dose for gestational period
5 mSv (0.5 Rem)
Fetal dose monthly not to exceed
5 mSv (0.05 Rem)
Leakage radiation cannot exceed
100 mR/hr. At 1 meter
Control panel of fixed unit must be… (3)
Behind protective barrier
Allow you to see patient
Indicate when tube is energized and exposure is made
Tabletop must be as ________ as possible
Radiolucent
Equipment must have an _____ indicator
SID
True or false: Must have beam limiting confine useful beam
True
Beam Limiting device must have SSD of ___.
15”
Collimator alignment must be within _____ of SID
+/- 2%
If beam operates at 70 kV or above, must have at least ____mm. Al filtration to decrease patient skin dose
2.5
_____ added + _____ inherent
- 0
0. 5
Used for screen-film combinations
Spectral matching
Used to improve quality of image but increase patient dose
Grids
Grids are used more frequently in ____ due to scatter sensitivity
CR
Use a ____ SSD for portables
12” (30 cm)
____ make up the matrix in DR
Pixels
Be aware of proper technique by checking “S” number to avoid ________
Overexposure (“Dose Creep”)
______ produces greatest diagnostic dose
Fluoro
To reduce fluoro patient dose you should…. (4)
Minimize fluoro time
Use intermittent fluoro
Collimate
Use correct techniques
SSD for fixed fluoro
15” (38 cm.)
SSD for C-arm
12” (30 cm.)
Type of fluoro that results in highest fluoro dose so use intermittent and “last image hold”
Cinefluorography
Type of fluoro used for interventionals so monitor and document fluoro time
HLCF (High-Level-Control Fluoro)
Personnel monitoring is required whenever workers are likely to risk receiving ___% or more of annual occupational EfD limit of 50 mSv (5 Rem) / year
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