1Health physics is?
The practice of providing radiation protection for radiation workers and minimizing dose to the public.
2The first radiation physicists worked with?
The atomic bomb
3What are health physicists involved with?
Research, teaching and operational aspects of radiation safety
4What do health physicist develop?
equipment, techniques, and procedures to control radiation levels to radiation workers, radiation physcists and the public
5what are the 3 cardinal principles of radiation protection
time distance shielding
6How is exposure measured
exposure rate x time
7how should pulsed progressive fluoro be used
to minimize dose
8tech is exposed to 10mR/hr for 15 minutes what is the total exposure
2.5 mR
9What happens to exposure as distance increases
exposure decreases
10what is the point source of radiation
x-ray tube target
11during fluoro what is considered the point source of radiation
the patient
12tech is recieving 100 mR/hr standing 2 feet away from patient during fluor, what is their exposure if they step back 4 feet from the patient
25 mR/hr
13what is 10th value layer is equal to how many half value layers
3.3
14If a technologist is receiving 2 mGyt/hr standing 1 foot from the patient during fluoroscopy, what is his rate of exposure when he steps back to a distance of 2 feet from the patient?
.5 mGyt/hr
15When using the inverse square law during fluoroscopy, the patient should be considered a(n) _____ source of radiation.
Point source
16If a technologist is exposed to 4 mGyt/hr for 45 minutes during a fluoroscopy exam, what will be her total exposure?
3 mGyt
17What is NCRP
National council of radiation protection
18NCRP makes __ regarding dose limits
recommendations
19what are the DL established by NCRP derived from
BEIR and NSC reports
20What does NCRP publish?
annual dose limits for public, occupational, and prenatal exposures
21Dose limits are based on a _____ dose-response relationship to radiation.
linear, nontreshold
22what is MPD (maximum permissible dose)
Dose that would be expected to produce no significant radiation effects (old term for dose limits)
23What is the best approach to occupational radiation exposure
using ALARA
24Dose limit for general public is __ the dose limit for occupational exposure
1/10th
25The concept of effective dose accounts for
Different types of radiation and RBE
Relative radiosensitivity of various tissues and organs.
26Dose limit is for __ exposures only
occupational
27basic annual effective dose limit for occupational exposure is?
5 Rem (5cSv)
28Dose limits are specified as?
effective dose
29What is tissue weighting factor?
describes the radiosensitivity of various tissues and organs
30what is radiation weighing factor?
describes type of radiation used
31what is the equation of effective dose?
radiation weighting x tissue weighting x absorbed dose
32what is dose limit for skin & thyroid?
500 mSv/ yr (50 Rem/yr)
33what is dose limit for exremities
500 mSv/yr (50 Rem/yr)
34what is dose limit for lens of eye
150 mSv/yr (15 Rem/yr)
35what is dose limit for public general public
5 mSv/yr (500 mRem/yr)
36what is the most radiosensitive stage of pregnancy
during major organogenesis (3rd-10th week of pregnancy)
37__% of conceptions would be reabsorbed after dose of 10 rad
.1%
38There is a __% increase in congenital abnormalities following a 10 rad fetal dose.
1%
39The DL for a declared pregnancy is?
.5 mSv/mo (50 mRem/mo)
40DL for fetus is?
5mSv/yr (500mRem/yr)
41What are management principles for pregnancy
New employee training, in-service training, counseling during pregnancy
42Pregnant patient can be radiographed if?
known and documented
433 ways to know if patient pregnant
elective booking, patient questionnaire, signage posting
44if x-ray is taken on a pregnant patient without knowing what must happen
contact medical physicist
45what is 10-25 rule
less than 10 rads no issue. greater than 25 rads therapeutic abortion. between 10 to 25 rads gray area
46who makes laws regarding dose limits
the state
47what is a dose limit
the dose at which would be expected to produce no significant radiation effects
48what are dose limits established for specifically
whole body, partial body, tissues and organs, general poplulation
49Whole body dose limits are based on what kind of dose response relationship?
linear, nonthreshold
50When a technologist becomes pregnant she should be issued what?
second personal monitoring device at waist level
51what is effective dose?
equivalent whole body dose
52what is whole body dose
the weighted average of the radiation dose to various organs and tissues