radiation protection/ radiation biology - test 2

1 R

2.58×10^-4

1 rad

100 erg/g

1 Gy

1 J/kg

List the three types of personnel dosimeters used to measure occupational exposure to radiation (no abbreviations)

1. Direct ion storage dosimeter (DIS)

2. Optically stimulated luminescence dosimeter

3. Extremity dosimeter (Thermoluminescent ring dosimeter [TLD])

1 coulomb

The quantity of the electrical charge flowing past a point in a circuit in 1 second

Early tissue reaction or early deterministic somatic effect

Biological damage resulting from radiation exposure that manifests itself in minutes, hours, days, or weeks after the exposure in the person receiving the exposure

Genetic effect

Biological damage resulting from radiation exposure that affects the offspring of the person receiving the exposure when the exposure was received preconception

Late tissue reaction or late deterministic somatic effect

Biological damage resulting from radiation exposure that manifests itself months or years after the exposure in the person receiving the exposure

Range of sensitivity for TLD

As low as 5 mR or 1.3×10^-6 C/kg

Range of sensitivity for OSL

1 mrem to 1,000 rem or 1 ųSv - 10 Sv

R (roentgen)

The traditional unit of dose measurement for exposure to x or gamma radiation

rad

The traditional unit of dose measurement for the amount of radiation transferred to biological tissue

Sievert

The SI unit of dose measurement for EqD or EfD

rem

The traditional unit of dose measurement for EqD or EfD

c/kg

The SI unit of dose measurement for radiation induced ionization in air

Gray

The SI unit of dose measurement for absorbed dose

TLD (ring dosimeter)

• Uses lithium fluoride as the radiation sensing material

• Can be read only once because the readout process destroys the stored information

• Can be worn for 3 months at a time

• Processed in an analyzer that heats the crystal layer which emits light in proportion to the amount of radiation received

• On going use is reasonably cost effective

OSL

• uses aluminum oxide as its radiation detecting layer

• Releases light when scanned by a laser in proportion to the amount of radiation received

• Has metal filters made of copper, aluminum, and tin/ not affected by heat, moisture, or pressure/ can be worn for a year at a time but is recommended to wear for 2 months

Direct ion storage dosimeter

• small ionization gas filled dosimeter connected to a solid state device

• Electrically erasable programmable read only memory (EEPROM)

• The amount of charge stored in the device is directly proportional to the amount of radiation exposure

• Can be read out through a physical connecting device such as a USB or via wireless connection

• Can be read out by the device wearer via a cellphone application

• Instant access to data and no need for institutions to collect individual dosimeters and mail in for a reading. GPS or microchip containing devices may be able to add data concerning the location of exposure even

• Built in memory chips may be used to store data on the user and the facility

Proportional counter

Is used in a lab setting to detect alpha and beta radiation and has no use in diagnostic imaging

Ionization chamber - type survey meter

• Can be used to measure exposure rate in diagnostic xray of an exposure time of 1 second or more is used

• Is the most accurate of the meters to measure exposure rate

• Can be used to measure the exposure rate and cumulative exposures of X-rays, gamma rays, and beta rays

• Used often for radiation protection surveys (i.e. to check for exposure rate during fluoro or protective barrier integrity)

Geiger muller counter

• Primary radiation detector used in nuclear medicine because it easily detects the presence of radioactive material

• Clicks or beeps in the presence of ionizing radiation

Air kerma

Kinetic energy released in a unit mass (kilogram) of air

Tissue kerma

The kinetic energy released in a unit mass of tissue

Dose area product

A measure of the amount of radiant energy that has been thrust into a portion of the patients body surface. DAP is usually expressed in units of mGy-cm². Given the appropriate values, you need to be able to compute the DAP. Be sure to convert Gy to mGy first!

what is the REM an acronym for?

Radiation equivalent man

what is the RAD an acronym for?

Radiation absorbed dose

You need to know the difference between equivalent dose and effective dose

Equivalent dose just uses your dose times your Radiation weighting factor and Effective dose is if you apply that one other factor, that tissue weighting factor

Equivalent dose

This quantity attempts to numerically specify the differences in transferred energy, and therefore potential biologic harm that are produced with different types of radiation.

Effective dose

this is a measurement of the overall risk arising from the exposure of biologic tissue and organs to radiation exposure, taking into account that does from all types of radiation, as well as the body part affected

what is the radiation exposure monitoring of any person occupationally exposed regularly to ionizing radiation?

Personnel dosimetry

effective dose takes into account the type of radiation, the energy, and the type of tissue, right? 
Equivalent dose takes into what?

Dose and the type of radiation

LET (linear energy transfer)

• average energy deposited per unit length of track

• Generally described in units of kilo electron volts (keV) per micron (1 micron [ųm] = 10^-6 m)

if I give you a list of modalities and I ask you which is going to yield the highest occupational exposure, what kind of modalities, what kind of exams are we looking for here?

Special procedures fluoro

Let's say you're wearing an apron, you have on an apron, where should your primary dosimeter be located outside the apron?

Collar level, In front on the Anterior outside of the apron

Let's say you don't wear don't wear a lead apron. 
You're just doing a hand. Where should your badge be?

Collar level, anterior, thyroid level

we said that personnel dosimetry was used, right, to measure dose. What can that tell us? What can it tell us about the employee?

Their working habits, their radiation protection habits, provides a permanent record of dose that they received during a certain amount of time, Maybe a little bit more about the facility, and indicate the safety of an employee's working conditions

When do you have to expose your monitoring of occupationally exposed personnel they're likely to receive what percent or more above the annual effective dose limit?

10%

What is the annual effective dose limit of occupationally exposed personnel?

0.05 Sv or 50 mSv

Where do you wear an extremity dosimeter?

Finger

The extremity dosimeter is on the hands to measure what?

The dose to the hands

If your organization requires you to wear a secondary dosimeter during an exam that requires you to wear a lead apron, where should you wear the secondary dosimeter?

Waist level under the apron

if you are an occupational worker or a student and you are pregnant, where should you wear your fetal badge?

Anterior Waist level

What do you find on a dosimetry report?

• deep penetrating dose

• Shallow non penetrating dose

• Lens of the eye

which is used to detect ionizing radiation above background or to measure exposure rate. What do we call those collectively?

Radiation survey meters

What does a personnel dosimeter measure?

Employees dose

If dose is in rads and you're calculating the equivalent dose, if your dose is in rads, what's your equivalent dose in. R

REM

if you are doing effective dose and your dose is in gray, what is your effective dose going to be in?

Sieverts

what's your formula for collective effective dose?

• Effective dose x number of people exposed

• Can be in mrem or person sievert

Why do you wear the primary dosimeter at collar level? What is it we're measuring?

The approximate dose received by the Thyroid and eyes

A controlled dosimeter badge should be kept in a location where it will not receive any what?

Ionizing radiation exposure

of the three dosimeters, which is the most popular monitoring device you used today?

OSL

Which dosimeter is used to create a glow curve that is consulted to see how much radiation a dosimeter received?

TLD and OSL

give me another name for the ionization chamber type survey meter

Cutie pie

as your atomic number of the part goes up, 
What happens to your absorbed dose?

It goes up

What happens if your mass density of the part goes up, what happens to your absorbed dose?

It goes up

as the photon energy goes up, what happens to absorb dose?

It goes down

Fetal dosimetry monitors, are those considered primary or secondary monitors?

Secondary

why is DIS dosimeters becoming the new latest and greatest?

they can be popular because they're lightweight, they're durable. They can be dropped or scratched with little chance of harm to the device

Why do we have to keep a record of exposure as a permanent part of the employment record of all radiation workers?

It’s legally required

What does the letter M mean under the current or cumulative reporting period?

That the person received a minimum exposure, meaning it was below 1 millirem

1 millirem, how do you convert it to rem? What would it be?

Divide by thousand, So that'd be 0.01 REM

if the radiation worker changes their place of employment, their exposure record data should what?

Should go with them