Outcome 2 Flashcards
What is a “controlled” area?
It is the area that is under supervision of an individual in charge of radiation protection.
It is an area that requires the employee to follow well established procedures aimed at controlling radiation exposure.
What are the 4 criteria for control?
- Controlled access
- Controlled occupancy
- Controlled working conditions
- Controlled escape of radiation (scatter)
What are the three population groups?
- Nuclear energy worker (NEW)
- Pregnant NEW
- Public
What changes for the pregnant NEW in regards to exposure?
Dose limit is dropped to 4 mSv for the remainder of the pregnancy.
What is the distinction between NEW and the public in terms of equivalent dose limits?
It is by the factor of 10.
Public limits are for adults, pregnant adults and children. T/F
False.
Just adults.
Pregnant and children, no exposure is preferred.
What does EFFECTIVE DOSE mean?
It is the sum of all equivalent dose of radiation received by each organ/tissue multiplied by the tissue/organs weighting factors
What does EQUIVALENT DOSE mean?
It is the absorbed dose multiplied by the radiation weighting factor.
What is the equivalent dose limit for the LENS OF EYE for NEW and public?
NEW - 50 mSv/yr
Public - 15 mSv/yr
What is the equivalent dose limit for SKIN for NEW and public?
NEW - 500 mSv/yr
Public - 50 mSv/yr
What is the equivalent dose limit for HANDS/FEET for NEW and public?
NEW - 500 mSv/yr
Public - 50 mSv/yr
What does the equivalent dose account for?
The degree of harm of different types of radiation
What I gathered:
Equivalent = how damaging the type of radiation is to tissues
Effective = how susceptible tissues are to radiation (they have different radiation sensitivities)
What is safety code 35 regulating?
Radiation EMITTING DEVICES
So x-ray department
What are the emergency limits?
Whole body EDL - 500 mSv
Skin EDL - 5000 mSv
What is the ambient controlled area dose rate limit for controlled/licensed area (NEW) and public?
NEW - 25 uSv/h
Public - 2.5 uSv/h
Signs must be posted at every point of access to any area that holds radionuclides _____.
It also should be posted in areas that has a probability of a person entering and receiving a dose rate in excess of _____.
A) >100 EQ
B) 25 uSv/h
What is EQ?
Exemption quantity
It is the quantity of radionuclide below which licensing is required by CNSC
Properties of EQ:
- It is different depending on how biologically damaging the radionuclide is.
- The less damaging, the higher the EQ can be.
No hospitalization is required and minimal precautions is needed for patients who have a load of:
Less than 300 MBq and radiation dose at 2m = less than 4 uSv/h
Precautions should be taken for patients with the load of:
Less than 1100 MBq and radiation dose at 2m = less than 16 uSv/h
Patients should be isolated in the hospital and under strict precautions if their load is:
Greater than 1100 MBq and have a radiation dose at 2m greater than 16 uSv/h
What is Annual Limits on Intake (ALI)?
It’s the dose limits for contamination that a NEW might ingest/inhale/absorb.
Based on the radionuclides’ ability to damage tissue.
What is the management’s responsibilities?
- implementing policies and procedures to maintain ALARA (resources and training)
- establish action levels and communicate them
- track and evaluate NEW exposure doses
- provide feedback
What are the NEWs responsibilities?
- know and understand radiation protection practices
- comply with all ALARA policies
- be familiar with emergency procedures
- know who is RSO
What are the 8 elements of ALARA?
- Commitment to safety and good radiation protection at all levels from NEW to management.
- Implementation that includes organization and management
- Resources
- Training
- Action levels - amt of exposure or activity that requires specific safety procedures
- Documentation
- Performance targets, working plans and predictions of potential high exposure
- Operational reviews
What is the value of EQ that is exempt from CNSC regulations?
1 EQ
What is the EQ for Tc-99m? I-131?
Tc-99m = 10 MBq
I-131 = 1 MBq
How do you classify radionuclides?
Based on their radiological properties and ability to cause biological damage.
Which class is most damaging?
CLASS A - mostly alpha emitters
what does class B contain?
Beta emitters
Which class is least damaging?
Class C - ones that emit gamma only
What are some examples of class B radionuclides that we use?
Mo-99 and I-131
What are some examples of class c radionuclides that we use?
Tc-99m, Tl-201, I-123, F-18, In-111 and Ga-67
What is ACTION LEVEL?
amt of exposure or activity that requires specific safety procedures
____ time to deliver an exposure dose = _____ biological effect.
Less time, greater biological effect
___ to the whole body = death
5Gy Acute dose
