Lecture 9- Radiation Safety Flashcards
what is the biggest source of radiation to the US momulation
radon or medical imaging
what is the biggest source of radiation to the US momulation
radon or medical imaging
what is the difference between Denver and New ORleans
Denver has more radiation
what is the typical annual radiation to a human
.2mSV
what is cosmic radiation
cosmic ray particles originate from outside the solar system and from solar flares. When striking the earths upper atmosphere, particles are defected by van Allen belts. Radiation at Earths surface includes primary ET radiation secondary radiation showers which are particles from the upper atmosphere having collisions
does radiation decrease with elevation
no it doubles every 5000 feet
is exposure higher with air travel
yes, and frequent fliers
how much extra radiation do airline crews and frequent fliers recieve
1mSv annullay
is radiation higher at equator or poles
it is higher at the poles
what is the dose percent decrease between indoor and outdoor
indoor is 20% less than outside
what is terrestrial radiation
radioactive things in the soli and primordial radionucelotides. Radioactive atoms with half-lives comparable to the age of the earth.
what primordial radio nucleotides are most radioactive
K-40 and uranium 238 and thorium 232
what is beta radiation
it is electrons like aluminum foil
what is beta radiation
it is electrons like aluminum foil
what is the difference between Denver and New ORleans
Denver has more radiation
what is the typical annual radiation to a human
.2mSV
what is cosmic radiation
cosmic ray particles originate from outside the solar system and from solar flares. When striking the earths upper atmosphere, particles are defected by van Allen belts. Radiation at Earths surface includes primary ET radiation secondary radiation showers which are particles from the upper atmosphere having collisions
does radiation decrease with elevation
no it doubles every 5000 feet
is exposure higher with air travel
yes, and frequent fliers
how much extra radiation do airline crews and frequent fliers recieve
1mSv annullay
is radiation higher at equator or poles
it is higher at the poles
what is the dose percent decrease between indoor and outdoor
indoor is 20% less than outside
what is terrestrial radiation
radioactive things in the soli and primordial radionucelotides. Radioactive atoms with half-lives comparable to the age of the earth.
what primordial radio nucleotides are most radioactive
K-40 and uranium 238 and thorium 232
what is alpha radiation
helium nun which is lungs
what is beta radiation
it is electrons like aluminum foil
hw does the radiation from the terrrestrial sources get into the body
into the lungs because partcles are inhaled from the soil
how does radon usually get into the body and what kind of radiation is it
alpha radiatin and it is breathed in
what is the largest background source of radiation
radon
what is radon from and the half life
it is from uranium 238 and it is from alpha decay with a half life of 3.8 days
what building feature is important for radon exposure
ventilation is important
what unit are radon levels measured
it is measured through picoCuries per Liter
what is the disadvantages to film badge
requires processing and no direct readout, and excessive moisture and heat may damage the film
what is the primary internal radiation and where is it found
muscle and pottasium-40
what are the highest source of artificial radiation
medical exposures and mostly diagnostic xrays
what causes cigarettes to be radioactive
they have polonium
what is the dose from cigarettes
it is usually 16- mSV to bronchial epithelium and 13 mSV effective dose. More than a CT
what occupation has the highest occupational exposure and how does that compare to people working in radiology
uranium miners have 12 mSV as dose and radiologists and radiology techs are 1-.7
what is the typical dose for a an interventional radiologist and cardiac cath lab staff
it is 18 and 5
where do you wear a personal dosimeter
front torso when no apron or collar with apron
what are the three main types of peronnel dosimeters
film badges, storage phosphor dosimeters, pocket dosimeters
how does a film badge work
radiation darkens the film proportional to the dose. Energy of radiation is determined by including metal filters in front of part of the film.
what does the report include for film badges
a shallow does (skin dose) and beta radiation. It has a deep dose which is penetrating radiation and includes X-ray
what are the advantages of a film badge
wide recorded exposure range, durable and rugged, permanent record, and economical
what is the range for x-rays and beta radiation of a film badge
xray is 100uSV-15SV
beta radiation- 500uSV-10SV
what is the disadvantages to film badge
requires processing and no direct readout, and excessive moisture and heat may damage the film
what are storage phosphor dosimeteres
includse a material that traps radiation even in excited energy state. Some storage process with trap plus record event and event changing electronstrugcture energy is given off proportional todos record
what materials are used
TLD- lithium fluoride, and OSL which is aluminum oxide activated with carbon. Both types are configured with filters for radiation energy determination
what is the advantage to storage phosphor dosimeters
wide recorded energy range and can be reused. It is 10uSV to 10SV
what is the disadvantage to storage phosphor dosimeters
requires processing-no direct readout, destructive readout for TLD and OSL can be verified by repeating a few times. higher cost than film
what is a pocket dosimeter
used for high exposure situations.
what are the types of pocket dosimeters
G-M tubes, radiation, ion chamber, sensitive diodes
what is the main region for the gas filled detector
it is the geiger muller region draw it and it is the cascade of events happen
what are the disadvantages
initial cost
make a summary chart for these
see slide on the 11 page
how does gas-filled detector work
gas is ionized by radiation ions are collected and converted to signal. Incoming radiation ionizes the gas and converted to electrical signal
how does a scintillator work
there is emission of light from radiation interactions
how does a semi-conductor reactor work
they are semi-conductor crystals of Silcon or geranium with impurities so they act as a diode and allows current flow after a radiation interaction
what are the types of detector in terms of usage
counters, spectrometers, dosimeters
what is a counter detector
determines the number of radiation interactions
what are spectrometers
they determine the energy distribution or spectra of radiation