Brain Teaser #8

A) Question:

This unit is a measure of ionization produced in air?

A) Answer:

The unit that measures ionization in air for photons, and is the unit of exposure, is the Roentgen (R). The SI unit is coulomb per kilogram.

B) Question:

If you measure the exposure in air to be .90 Roentgen, what is that in coulombs per kilogram?

B) Answer:

.90 Roentgen is equal to 2.32 X 10-4 coulomb per kilogram.

Follow Up:

1 Roentgen = 2.58 X 10-4

To find .90 Roentgen simply multiple by 2.58 X 10 -4

(.90 ) (2.58 X 10-4) = 2.32 X 10-4

C) Question:

What is the unit used to express absorbed dose?

C) Answer:

Gray or rad is used to express absorbed dose. The Gray is the SI unit.

D) Question:

1.5 Gray is how many rads?

D) Answer:

1.5 Gray is equal to 150 rads.

Follow Up:

1 Gray = 100 rads

simply take 1.5 Gray and multiple it by 100 rads

( 1.5)(100) = 150 rads

please note also that 1 rad = 1 cGy

E) Question:

What unit best describes absorbed dose and the equivalent biological damage?

E) Answer:

This is dose equivalent and rem or sievert best describes the unit for equivalent biological damage. The sievert is the SI unit.

F) Question:

If a patient was exposed to 1.8 Gray of proton particles with an average quality factor of 10, what would be the dose when considering equivalent biological damage? Please use the unit sievert.

F) Answer:

The patient would be exposed to 18 sievert.

Follow Up:

This uses the equation:

(absorbed dose)(quality factor) = DE (damage equivalent)

(1.8 Gray)(10) = 18 sievert.

G) Question:

18 sievert is equal to how many rem?

G) Answer:

18 sievert is equal to 1800 rem.

Follow Up:

1 sievert = 100 rem

simply take 18 sievert and multiple 100 rem

(18)(100) = 1800 rem

H) Question:

What is the definition of a Becquerel?

H) Answer:

One Becquerel is the quantity of a radioactive material that will have 1 transformation (or disintegration) per second.

I) Question:

How many Becquerels are in one Curie?

I) Answer:

3.7 X 1010 Becquerel = 1 Curie

J) Question:

What is the permissible dose for a radiation worker's whole body?

J) Answer:

A radiation worker is allowed to receive 5 rem (50 mSv) for the the whole body for the year.

K) Question:

Once a pregnancy is declared, what is the maximum amount of dose this person can receive per month?

K) Answer:

A pregnant female can receive a maximum of .05 rem/month or .5 mSv/month


Author: Adam Buell
Editors: Mary Hare
Date Created: July 2005