Outcome 6 Flashcards
What three things does the list of designated rooms need to have on it?
1) license number and room designation
2) address/location of the licensed area
3) contact person
How do you know that you are in a controlled area?
- radiation warning signs at the boundaries
- signage and warning symbols IN the room
What are the 5 different types of postings?
- CNSC license
- CNSC room classification safety posters
- radiation warning signs
- 24h emergency contact
- radiation signs and labels on containers
Where is the 24hr emergency contact for the site found?
- at the boundaries of the controlled area so a person can easily see who must be contacted
What are the requirements for CNSC room classification safety posters?
- needs to be posted in any room where >1 EQ of unsealed nuclear substance is used
- indication of what type of room it is
- must be visible
What are the 5 different room classifications?
- basic
- intermediate
- high-level
- containment
- nuclear medicine level
What are the specification for the radiation warning symbol?
- atom exploding with 3 blades, but one blade downward and centered on the vertical axis (reddish purple/black)
- yellow background
- appropriate size for the container/area
- no wording superposed on it
What is the criteria needed for a radiation warning sign in a controlled area?
> 100EQ of nuclear substances within the boundaries
possibility of anyone entering the area to receive an ambient dose of >25 uSv/hr
How should containers containing nuclear substance be labelled?
- radiation warning sign outside with “rayonnement-danger-radiation” on it
- needs the NAME, QUANTITY (Bq), DATE OF MEASUREMENT, FORM of nuclear substance on it
When do you not need to label containers?
- if the container is used to hold nuclear substances for IMMEDIATE use and is UNDER DIRECT SUPERVISION
- if the nuclear substance is =<1EQ
When do you deface the radiation symbol found on signs and labels?
- when there is no more nuclear substance present (think decay storage and how when there is no more left you can throw it into regular municipal garbage, you got to deface the radiation sign)
- when the label leaves the lab without actually being on a radioactive container
How do you temporarily commission an area?
- posting a radiation warning sign
- setting up radiation protection equipment to meet time, distance, shielding
- need decontamination kit/supplies available
What is “commissioning” a room?
typically an area where you set up a place where nuclear substances will be used temporarily
What are the steps typically needed to decommission an area?
- monitoring by wipe tests, ambient testing)
- removing all signs and warnings
What does monitoring external and internal exposure for control mean?
it is to assess the amount of ionizing radiation or radioactive contamination in a room/area/building
How is the external and internal exposure assessed?
use of survey meters and wipe tests
What are the two types of ambient dose rate monitoring done?
1) periodical (weekly)
2) continuous
How do you assess the weekly monitoring?
use of survey meters in the controlled area and adjacent public areas
How is the ambient dose rate measured continuously?
with the use of GM counters
When are continuous ambient dose monitoring required?
in intermediate and high level radiation areas
What is the ambient dose rate limit for the PUBLIC?
2.5 uSv/hr
What is considered the “PUBLIC” in terms of ambient dose rate limits?
any area surrounding a room/area that contains nuclear substances that has potential to expose the public
What is the ambient dose rate limit for a CONTROLLED AREA? What’s the rationale?
25 uSv/hr
it is the effective dose limit for the NEW per year divided by a 40 hour work week for the year.
How often are survey meters supposed to be calibrated?
once every 12 months by a CNSC certified service
How long are records of calibration kept for?
a minimum of 3 years
Do you need to do a daily calibration check still? what are you checking?
yes.
- batteries
- audible response
- calibration date check
- source check
What is contamination?
radiation where it shouldn’t be
What are the two kinds of contamination? What is the difference?
Fixed and (non-fixed) removable
fixed - can’t be removed from the surface during normal conditions of transport
non-fixed - can be removed from surface during normal conditions of transport
What is the CNSC removable contamination limits for a controlled area for the different classes of radionuclides?
Class A: 3 Bq/cm2
Class B: 30 Bq/cm2
Class C: 300 Bq/cm2
What is the CNSC removable contamination limits for a public area for the different classes of radionuclides?
Class A: 0.3 Bq/cm2
Class B: 3 Bq/cm2
Class C: 30 Bq/cm2
What is the difference between DIRECT and INDIRECT method for contamination monitoring?
direct - measures both fixed and non-fixed contaminations
- uses detectors and monitors directly over the area
indirect - measures only non-fixed (removable) contaminations
- use of wipes and the well counter
What is the evaluation of wipes formula?
Removable Activity = (N-NB)/(E x 60 x A x (F))
Removable Activity = (N-NB)/(E x 60 x A x (F))
N = wipe (cpm)
NB = bkg (cpm)
E = instrument efficiency (decimal)
60 - time (s)
A = area wiped = 100cm2)
F = collecting factor = 10% is normal (0.1)
therefore, formula is usually…
Removable Activity = (N-NB)/(E x 60 x 100cm2 x 0.1)
What is the purpose of an emergency procedure?
- limits spreading of contamination
- to detect the quantity of nuclear substances
- decontamination of the area, workers, equipment and other persons
- monitoring
What is the difference between a minor and major spill?
minor - <100EQ
major - when it is a volatile substance, when personnel get contaminated, and when it is >100EQ
When does the CNSC have to be contacted? And within how many days does a formal report need to be submitted?
- a major spill
- emergency situation where EDL or ALI is exceeded
*within 21 days
What do we use as “evidence” that we are practicing ALARA and CNSC compliance?
the radiation safety manual and generated records
What defines a licensed area?
area where occupational exposure is under the supervision of someone in charge of radiation protection
What are the warning labels below the radiation warning symbols?
they describe the nature of the radiation and the hazard to allow for increased safety measures
What are the 5 different types of warning labels found underneath the radiation warning symbols?
- restricted area
- caution radiation area
- high radiation area
- caution radioactive material
- airborne
What is the meaning of “Restricted Area”?
there is a dose rate of 20 uSv/h - 50 uSv/h
What is the meaning of “Caution Radiation Area”?
possible dose rate of 50 uSv/h
What is the meaning of “High Radiation Area”?
1.0 mSv/h with GM present
What is the meaning of “Caution Radioactive Material”?
radioactive storage area
What is the meaning of “Airborne” on a warning label?
a dose rate that exceeds ALI in air
What shouldn’t you do when trying to prevent absorption of contaminants on skin?
- no hot water (encourages blood flow to the area)
- don’t use highly alkaline soaps or organic solvents
- don’t use abrasive detergents
Worry about injury after decontaminating yourself. T/F
False.
tend to the injuries before starting decontamination
What is the area decontamination procedure?
- seal off the area and make sure no one needs medical assistance
- put absorbent pad on spill
- clean up as much radioactivity as possible with tongs
- pad again
- spray with detergent then bundle and dip paper towel into water to clean the area
- use pad again to absorb the water
- wipe test to see if its activity
