Cedo - (Section 5) Biological Effects Of Radiation

Question 0

Describe the prompt health effects for the following doses;

0-250 mSv
250-500 mSv
500-1000 mSv (1Sv)

Answer 0

0-250
No obvious injury.

250-500
Temporary blood changes but no serious injury.

500-1000
Blood and cell changes, some injury, no disability.

Question 1

Effects of exposure to radiation can be grouped in what 2 general categories?

Answer 1

Prompt and delayed effects.

Question 2

Describe the prompt health effects for the following doses;

1-2 Sv
2-4 Sv
5-10 Sv
10+ Sv

Answer 2

1-2
Injury, possible disability.

2-4
Injury, certain disability, possible death.

5-10
Fatal to 50% of victims within 30 days.

10+
Fatal to all people.

Question 3

What are the radiation effect classifications?

Answer 3

• Acute (Prompt) effects.
• Long-term (Chronic) effects.
• Somatic effects.
• Genetic effects.

Question 4

Describe acute (prompt) effects.

Answer 4

Those appearing within minutes, days or weeks.

Question 5

Describe long-term (chronic) effects.

Answer 5

Those which appear years or generations later.

Question 6

Describe somatic effects.

Answer 6

Refers to radiation injury to the person involved but not to reproductive cells.

Question 7

Describe genetic effects.

Answer 7

Refers to radiation exposure that results in some chromosome damage, thus affecting future generations.

Question 8

Name some Radioresponsive tissues in the human body.

Answer 8

• Blood forming organs: Bone marrow, spleen, etc
• Sex organs: Gonads, uterus, etc
• Other organs: Liver, lens of eyes

Question 9

Name some Radioresponsive tissues in the human body.

Answer 9

• Connective tissue: Tendons, ligaments, etc
• Muscle
• Fat
• Bone
• Brain
• Nerves

Question 10

How much is the approximate assumed background radiation exposure per year?

Answer 10

1 mSv/year

Question 11

Because of the unknown risk from long-term, low level exposure, CEDO’s must?

Answer 11

Control exposure to the “ALARA” (as low as reasonably achievable) principle.

Question 12

What does ALARA stand for?

Answer 12

As Low As Reasonably Achievable.

Question 13

What’s the most important characteristic of Gamma-rays?

Answer 13

Their ability of them to ionize the atoms of the material through which they pass.

Question 14

What does MPD and EDL mean?

Answer 14

Maximum Permissible Dose and Effective Dose Limit.

Question 15

Radiation dose limits are recommended by who?

Answer 15

International Commission on Radiological Protection (ICRP).

Question 16

What is the purpose of a dose limit system?

Answer 16

To ensure a dose of radiation, based on current knowledge, is not expected to cause bodily injury to a person during their lifetime.

Question 17

No licensee shall authorize the use of a exposure device that?

Answer 17

• Does not appear to functioning proper and,

- has a radiation intensity of more then 2 mSv/hr on any part of the surface [NSC Device Regulation, Section 30(4)].

Question 18

What does NEW stand for?

Answer 18

Nuclear Energy Worker.

Question 19

A Nuclear Energy Worker (NEW) is defined in the NSC Act as?

Answer 19

A person who is required by occupation to perform duties that may cause one to receive a dose of radiation in excess of the prescribed limit for the general public.

Question 20

A NEW that becomes pregnant must?

Answer 20

Immediately notify the licensee in writing. Dose limits will then change for the duration of pregnancy.

Question 21

What are the MPD limits?

Answer 21

NEW’s, including pregnant NEW’s

• 3 months - 30 mSv (can not exceed the 1 year dose)
• 1 year - 50 mSv
• 5 year - 100 mSv
• Emergency/Source retrieval - 500 mSv to body and 5000 mSv to skin

Pregnant NEW
- Balance of pregnancy - 4 mSv

A Non-NEW

• 1 week - 0.1 mSv
• 1 year - 0.5 mSv
• 1 calendar year - 1 mSv

Question 22

What’s the Equivalent Dose Limits for the following organs;

• Lens of eye
• Skin
• Hands and feet

Answer 22

Lens of eye

• NEW - 150 mSv/yr
• Non NEW - 15 mSv/yr

Skin

• NEW - 500 mSv/yr
• Non NEW - 50 mSv/yr

Hands and feet

• NEW - 500 mSv/yr
• Non NEW - 50 mSv/yr