Biological Effects and Radiation Dose

Question 1

Define Roentgen

Answer 1

A measure of the ionization produced in air by x-ray or gamma radiation

Question 2

What are the four stages of the radiation syndrome

Answer 2

1. Radiation illness
2. Apparent recovery
3. True illness
4. Death or recovery

Question 3

Define LD 50

Answer 3

The dose at which 50% of the people exposed die within 30 days without medical treatment (about 400 Rem)

Question 4

Name two specific plant locations where tritium is likely to be found

Answer 4

1. Containment
2. Spent Fuel Pit/Refueling Water

Question 5

Radiation that interacts with a molecule in the cytoplasm of the cell which results in the formation of ions or radicals which could react with important molecules of the cell resulting in permanent damage is what type of cellular damage.

Answer 5

Indirect

Question 6

What is the quality factor (QF) for alpha radiation

Answer 6

20

Question 7

What is the quality factor (QF) for neutron radiation

Answer 7

10 (fast) 2 (slow/thermal)

Question 8

Define REM

Answer 8

Roentgen Equivalent Man. REM = (RAD)(QF)

Question 9

What is the quality factor (QF) for beta/gamma radiation

Answer 9

1

Question 10

Rank 10 tissues in order of radiosensitivity

Answer 10

1. Lymphoid
2. Immature blood cells
3. Gastro Intestinal cells
4. Gonads
5. Skin
6. Blood vessels
7. Liver and adrenal cells
8. Bone
9. Muscle
10. Nerve cells

Question 11

Radiation that interacts with an important molecule causing a change or break in the molecule that could result in a mutated cell as it reproduces is what type of cellular damage

Answer 11

Direct

Question 12

Define LD 100

Answer 12

The dose at which 100% of the people exposed die within 30 days without medical treatment (about 600 Rem)

Question 13

Define RAD

Answer 13

Radiation Absorbed Dose. A measure of the absorbed dose of any ionizing radiation in terms of energy absorbed per mass.

Question 14

State the three methods of tritium production

Answer 14

1. Ternary fission (three fragments) produces more tritium than all other sources but is contained in the fuel rod.
2. Soluble Boron Production
   
   • Boron 10 interacts with a neutron
3. Soluble Lithium Reactions
   
   • Lithium 7 or Lithium 6 interacts with a neutron
   • Lithium 6 produces more tritium than Lithium 7

Question 15

Classify the four types of radiation as either internal or external hazards.

Answer 15

Alpha & Beta = internal hazard

Gamma & Neutron = external hazard

Question 16

What three actions can be taken to reduce the harmful effects of tritium

Answer 16

1. Introduce engineering controls to reduce source
2. If airborne cannot be reduced, stay time limitations
3. If waterborne, then avoid absorption of tritium through the skin