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RADT 465: Rad. Prot.
Radiation Protection
Question | Answer |
---|---|
True or False: Are wavelength and frequency inversely related? | True (Saia, pg. 229) |
What is the equation for the speed of light? | Frequency x wavelength (Saia, pg. 229) |
What is the largest source of artificial/man-made ionizing radiation exposure to humans? | Medical radiation exposure (Saia, pg. 229) |
What does the Law of Bergonie and Tribondeau state? | That the most radiosensitive cells are young, undifferentiated, and highly mitotic cells (Saia, pg. 237) |
What is the most radiosensitive cell? | Lymphocyte (Saia, pg. 237) |
What are ways to reduce risk of radiation to recently fertilized ovum? | Elective scheduling/10 day rule, patient questionnaire, posting (Saia, pg. 237) |
What are the acute radiation syndromes? | Hematopoietic, Gastrointestinal, Central Nervous System (Saia, pg. 237) |
What are the stages of acute radiation syndrome? | Prodromal, latent, manifest illness, recovery or death (Saia, pg. 237) |
What is the definition of wavelength? | the distance between two consecutive wave crests (Saia, pg. 225) |
What is the number of cycles per second? | frequency (Saia, pg. 225) |
What is the unit of measurement for frequency? | hertz (Saia, pg. 225) |
How much of the x-ray beam is comprised of Brems? | 70%-90% (Saia, pg. 227) |
What is attenuation? | The gradual decrease in exposure rate as ionizing radiation passes through tissues (Saia, pg. 227) |
What is ionization caused by? | high-energy, short-wavelength electromagnetic radiations that break apart electrically neutral atoms (Saia, pg. 229) |
What are some beam restrictor types? | aperture diaphragm, cone/cylinder, collimator (Saia, pg. 250) |
Why do we use beam restriction? | reduces patient dose, reduces production of scattered radiation, improves image quality (Saia, pg. 250) |
What does mAs do? | controls quantity-no effect on quality (Saia, pg. 252) |
What does kV do? | controls quality, affects quantity (Saia, pg 252) |
What is the most important way to reduce patient dose? | beam restriction (Saia, pg. 252) |
When should gonadal shielding be used? | the gonads lie in, or within 5 cm of, the collimated field; the patient has reasonable reproductive potential; diagnostic objectives permit (Saia, pg. 255) |
What do primary barriers protect from? | the useful beam (Saia, pg. 272) |
What do secondary barriers protect from? | scattered and leakage radiation (Saia, pg. 272) |
When should a person be required to wear a dosimeter? | when the receive .1 of the annual dose (.5 rem) (Saia, pg. 269) |
How many mm should protective lead aprons be? | at least .25 mm Pb equivalent (Saia, pg 271) |
What type of switch should the exposure be on x-ray units? | dead man type (Saia, pg. 271) |