Controlling Dose Flashcards
What are the 3 basic ways to protect yourself from radiation?
Time
Distance
Shielding
How do we calculate intensity?
- Use a survey meter.
- Apply Characteristic Intensity to the activity of the source
eg. Cobalt 60 = 0.36 mSv/h per GBq @ 1m
1000 GBq of Cobalt 60 = 1000 x 0.36 = 360 mSv/hr
What is the formula for determining Dose?
Dose = Intensity x Time
Which formula is used to determine
Intensity as a Function of Distance?
Inverse Square Formula
I1 = Original intensity
I2 = New intensity
D2 = New Distance
D1 = Original Distance
How many mSv/hr are allowed at a radiation barrier?
0.1
(as per CNSC Regulations)
Substance & Radiation Devices section 18 (1)(j)
How many mSv/hr are allowed within a storage area?
0.025
(as per CNSC Regulations)
How many mSv/hr are allowed on the surface of a device?
2
before use or upon installation of a new source
(as per CNSC Regulations)
Substance & Radiation Devices section 30 (4)(b)
How often does a survey meter need to be calibrated?
Once every 12 months.
(as per CNSC Regulations)
Facilities & Prescribed Equipment section 18 (1)(a)
At what interval should a leak test be performed?
Once per year or upon installation of a new source.
(as per CNSC Regulations)
Substance & Radiation Devices section 18 (1)(3)
What length do long handled tongs need to be?
1.5 metres minimum
(as per CNSC Regulations)
Substance & Radiation Devices Section 31 (1)(b)(iii)
Audible Dosimeters need to alarm at these two levels.
5 mSv/hr
or when dose reaches 2 mSv
(as per CNSC Regulations)
Substance & Radiation Devices section 31 (1)(f)(ii)
What material does a source tag need to be made of?
Steel or Brass
(as per CNSC Regulations)
Substance & Radiation Devices section 30 (1)(a)
What range does a survery meter need to be able to measure?
20 µSv - 100 mSv/hr
(as per CNSC Regulations)
Substance & Radiation Devices section 31 (1)(a)(i)
