Radiation Safety

Question 1

The 2 types of EMR

Answer 1

ionizing (harmful)

non-ionizing (mostly harmless)

Question 2

ionizing radiation can be classified as?

Answer 2

particulate - alpha and beta

wavelike - X-rays & gamma rays

Question 3

alpha radiation

Answer 3

heavy mass
positively charged
2 protons, 2 neutrons
-stopped easily even with thin material

Question 4

beta radiation

Answer 4

low mass
positive or negatively charged
positive called positrons, negative called electrons
-stopped easily

Question 5

gamma rays

Answer 5

high energy
no mass
highly penetrate tissues
-stopped by concrete or lead

Question 6

x-rays

Answer 6

high energy
short wavelength
penetrates tissues
-stopped by concrete or lead

Question 7

3 interactions of x-rays

Answer 7

1. absorption (pt gets dose)
2. transmission (passes through pt with no interaction)
3. scatter (incoming photon interacts with outer electrons on the target and changes direction and loses energy)

Question 8

RAD

Answer 8

The energy transferred from ionizing radiation per unit mass of irradiated material

A measure of radiation levels in the OR from radiation sources

Question 9

REM

Answer 9

A measure of the type of human tissue exposed by specific forms of radiation
Ex: a measure of the type of human tissue exposed (lens of the eye, thyroid, whole body) by specific forms of radiation (x-rays, alpha/beta particles)
Takes into consideration the type of radiation and the tissue exposed

Question 10

Law of bergonie and tribondeau

Answer 10

the radiosensitivity of cells is directly proportional to their reproductive activity and metabolic state and inversely proportional to their degree of differentiation

aka - tissues with high metabolic activity are more radiosensitive

Question 11

Linear Energy Transfer

Answer 11

A measure of the rate at which energy is transferred from ionizing radiation to soft tissue.
When the LET is high, ionizations occur frequently so the probability of interaction with the target molecule is higher

Question 12

Threshold Effects

Answer 12

Certain biological effects are caused when a radiation dose greater than some threshold value is received. Below the threshold value, no radiation effect is seen.

Question 13

Non-Threshold Effects

Answer 13

Adverse health effects that have been linked to chronic radiation exposures at lower levels include cataracts, epilation, cancer. Risk is not zero.

Question 14

ALARA means?

Answer 14

As low as reasonably achievable

Question 15

3 ways to limit radiation exposure?

Answer 15

Distance – from source
Duration – exposure time
Shielding – barriers