external and alternate dosimetry

specific gamma ray constant

measure of exposure rate, dose rate, or effective dose rate of a radionuclide at a specific distance

deep dose equivalent

whole body exposure at tissue depth of 1cm

deep dose equivalent only applies to what

irradiation from high energy photons

shallow dose equivalent

exposure to skin, extremities at a tissue depth of 0.7 cm

shallow dose equivalent applies to what

irradiation from beta particles, low energy photons, high energy photons

form 5 dosimetry report

occupational dose record for a monitoring period; usually generated yearly or quarterly (det. by previous X and job duties)

dosimetry reports give SDE and DDE for ___ and ___

whole body (badge)

extremities (ring)

film badge dosimeter

photographic film held b/w set of filters; when exposed to IR, it darkens in proportion to energy deposited

filters in film badge dosimeter allow for what

different radiation to be attenuated to determine difference bw SDE, DDE

pros of film badge dosimeter

cheap, durable, filters easily acceptable

cons of film badge dosimeter

sensitive to heat, film cannot be reused

thermoluminescent dosimeter (TLD)

solid state scintillation devices made w phosphor in a crystal structure

phosphors in TLD rings do what when exposed to energy

emit light

when TLD crystal is ionized, the electrons in the crystal lattice are…

released, “trapped” in impurities of the crystal.

when crystal is heated, electrons escape the “trap” and emit light

TLD rings: intensity of the light is ___ to the dose received

proportional

optically stimulated luminescent dosimeters (OSLDs)

operate like TLDs, but electrons are exposed to light instead

preferrable bc they can be reread many times but are also more expensive

electronic personnel dosimeters (EPDs)

offer instant readout of a user’s accumulated dose, as well as a current dose rate reading

EPDs have installed alarms to do what?

alert wearer when dose rate or accumulated dose is too high

EPDs are often used in conjunction with ___ bc they are not calibrated to the same standard

OLDs, TLDs

dose estimates: emergency scenarios

most ppl not wearing dosimetry, estimates must be made to determine care pathways

specific gamma ray constant used in conjunction w distance from a source and time of X to estimate full body dose

dose estimates from symptoms

often needed to estimate dose delivered based on symptoms manifesting rather than trying to calc a dose

examples of dose estimates from symptoms

time to induce vomiting

lymphocyte depletion kinetics

cytogenetic biodosimetry

lymphocyte depletion kinetics measure

change in WBCs

cytogenetic biodosimetry is

the “gold standard”

measures malformations in chromosomes, gives very accurate dose estimates