Section 2 Flashcards
Purpose of Dosimetry reports ? 3 main reasons
- Provide the individual with their radation exposure
- Provide the institution with radiation exposure
- Provide a method to keep radiation under ALARA
Radiation Dosimetry Reports comes out ________ or __________ in our case it is _______.
Monthly/or every other month/bimonthly
There are 8 main things on the Dosimetry Report
1.Individual Identification(5 digit # used for all activity and multiply badges) name ID #/Birth/Sex
2.Use (location and abbreviations are listed in a location chart; all radiation are assigned a location where it is worn)
3.Dose Equivalent for exposure period ( monthly or bimonthly readings )
4.Annual Dose Equivalent ( The annual dose equivalent given and individual exposure for a particular year)
5.Dosimeter(The type of dosimeter needed based on the radiation being monitored)
6.Radiation Quality ( Refers to the type and energies of a radiation)
7.Quarterly Dose Equivalent( Is the sum of an individuals exposure for a particular quarter of the year.)
8.Lifetime Dose Equivalent: (Lifetime dose equivalent gives and in ideal reading for the lifetime)
Deep- external whole body exposure=
1 cm
Eye : external exposure in the lens of the eye at
0.3 cm
Shallow Dose: external exposure to skin or extremity (includes hands) at
0.007 cm
Dosimeter type “P” measures
X-ray, Beta, Gamma
Dosimeter “ U” measures
TLD ring badge for X-ray, beta, gamma
P equals what type of radation?
X-ray and gamma
PH refers to what radiation
X-ray or gamma greater than 100 keV
PL refers to what radiation
X-ray or gamma ray less than 100 keV
PB refers to what radiation
Photons and beta mixture
What is Control Dosimeter?
It is a dosimeter included with each shipment, this is subtracted out of an individuals reading.
Minimal Dose Equivalent
Individuals that receive an “M” for their exposure means that they were exposed to an amount below what the dosimeter can measure.
Whole body minimal dose equivalent
1mrem for X-rays and gamma rays
Ring badge minimal dose equivalent
30 mrem for X-rays and gamma rays
Annual limits for whole body
5 rems/yr
Lens of the eye (annual)
15 rem/yr
Extremities and skin (annual)
50 rems/yr
Fetal
0.5 rem/gestation period
General Public
0.1 rems/yr
If an individual exceeds their limit of radation the _______ must investigate
Radiation Safety Officer
Two levels of investigation
- RSO will evaluate the cause,determine why overexposure occurred
- Investigational Level 2
-Evaluate the cause
-Notify employee in writing
-Provide and explanation of why the overexposure occurred
-Take corrective action to prevent this from happening in the future
———— are required to post certain information/signs in order to have radiation
Hospitals
Radiation Symbol is ______
Three bladed( Tri-foil symbol)
Colors of the radiation symbol
Magenta/Purple/or black on a yellow background
Radiation symbols has a center cross-match circle that …
matches the blades
Each blade of the radiation symbol should be …
60 degree angle
Type 1 of radiation area
Radiation areas
- Type of radation area
High Radiation area
- Type of radiation area
Very high radation
- Type of radiation area
Airborne Radioactivity area
5.Type of radiation area
Areas or rooms where licensed material is used or stored
Radation areas sign should read “caution radiation area” the limits required:
An area where an individual could receive a dose of 5 mrems in 1 hr at 30 cm
Radiation area that read “high radiation area posting:
An area where an individual could receive a dose equivalent of 100 mrem in 1 hr at 30cm should read CAUTION, HIGH RADIATION AREA OR DANGER HIGH RADIATION AREA
Radiation area with VERY HIGH RADIATION posting:
An area in where an individual could receive a dose equivalent to 500 rads in 1hr at 1 meter signs should read “GRAVE DANGER, VERY HIGH RADIATION AREA”
Airborne Radioactivy Area should read ‘’ CAUTION AIRBORNE RADIOACTIVITY AREA OR
DANGER,AIRBORNE RADIOACTIVITY AREA
Radioactive materials should be posted in areas/room that store or use amounts of licensed materials that exceed 10 times the quantity of such materials listed in appendix C to part 20
Appendix C has a list of radionuclides Tc99 is list with amount of 1 mCi so anything above that amount need a ‘’CAUTION RADIOACTIVE MATERIALS SIGN’’
Control radation areas have controlled access into their areas two main areas are
- High radiation
- Very High radiation
Each licensee shall ensure they have entrance or access point to a high radiation area with one or more of the following features:
1.A controlled device that causes level of radiation to be reduced below level at which and individual might receive a deep dose equivalent at 0.1 rem in 1 hr at 30 cm
2.A control device that energizes a visible or audible alarm signal
3.Entryways that are locked,except during periods when access to the area is required,with positive control over each individual entry
Additional measures to High Radiation areas
So an individual is not able to gain unauthorized access to areas in which the. Radiation levels could be encountered at 500 rads or more in 1 hr at 1 meter (extra security and electronic surveillance)
Exceptions to Posting Requirements in radioactive materials for periods of less than 8 hr if each condition are met:
1.Materials are constantly attended during these periods by an individual with radiation training
2.The area/room is subject to licensee control
3.Radiation level at 30 cm from the surface of the source does not exceed 0.005 rem/hr
4.If a patient given a radio pharmaceuticals meets the release requirements
- If the total effective dose equivalent to any individual from exposure to released individual is not likely to exceed 0.5 rem
Restricted area
An area of limited access that the licensee established for the purpose of protecting individuals against undue risks from exposure to radiation
Unrestricted
An area that is neither limited nor controlled by the license
Radiation containers that enter a hospital must have “caution radioactive materials” and the labels should have 5 things on it :
1.Radionuclide presents
2.Estimate of the quantity of the radioactivity
3.The date of the activity
4.Radiation levels
5.Kind of materials
* Licensee shall prior to removal of empty uncontaminated containers to unrestricted areas, removal/deface the radioactive material label
Contamination level is set by who?
Radiation Safety Officer
The level that is set by the radiation officer is called the
Dose rate trigger level anything above the trigger is contamination
Areas surveyed should be performed by an:
Geiger counter should read as low as 0.1 mrem/hr
Survey area will be performed at :
- The end of each day for all areas where radio pharmaceuticals are routinely prepared,administrated or used.
2.Once a week for all areas where radio pharmaceuticals or waste is stored
What do you do if you exceed your trigger level?
-Immediately notify the RSO they will initiate decontamination procedures
A record of the surveys must be kept:
- Survey must be kept for 3 years
- Calibration of the survey meter must be kept for 3 years
For survey records what is required:
- Date of the survey
- Trigger level established for each area
- The dose rate at each point in mR/hr
- The instrument used to make the survey
Wipe test are performed to survey removable contamination: 6 steps
- Wipe test should be performed 1 a week in all areas where radio pharmaceuticals are routinely prepared, administered or stored( wipe should be 100 cm^2)
2.A well counter is used to measure the removable contamination( should be read at 2000 distegrations per min )
3.Trigger level should be established for contamination - If the trigger levels exceeded, immediately contact the RSO
5.Records should be kept for 3 years - Should contain all information for a survey plus the removable contamination in each area expressed in dpm for 100 cm^2
Calibrations of instruments used for surveys must be:
- Before first used, annually and following repair( records kept 3 years)
- Survey meter is calibrated with reading up to 1000 mR/hr
- Two separate reading should be calculated on each scale that must be calibrated at 0.01,0.1,1,10,100
4.Each time a meter is calibrated you should note on the meter ( exposure rate from a dedicated check source, time and date of calibration) - You should perform a constancy check with your meter each day of use
-results should not differ by 20% from the calibration check
-These records are not kept
