Question

I S HIS 101 Midterm Ex. Translate Web Store iCloud Question 1 of 10 What is ALARA? As Low as Reasonably Achievable As Low as Realistically Achievable As Low as Reasonably Allowed As Low as Randomly Able Mark for follow up Question 2 of 10 ALARA is achieved through Time, Distance and Shielding True False Mark for follow up Question 3 of 10 The MRI scanner is turned off when not in use, posing no potential safety concerns or risk True False Mark for follow up Question 4 of 10 There is no problem bringing external metallic objects into the MRI scan room as long as there are no patients being scanned True False Mark for follow up

Answer 1

1) The answer is As low as reasonably achieved

This is the principle used in radiology which means making every reasonable effort to maintain exposures to ionizing radiations as far below the dose limits as practical.

2)The answer is true ALARA is achieved through time , distance, shielding.

TIME refers to the amount of time that is spent near the radio active source. it says to minimize the time near radiation area.

DISTANCE refers to how close a person is to the radiation source. It says maximize your distance from the radiation source.

SHIELDING refers to protecting yourself by putting something between you and the radiation source.

3) The answer is false.

This is because regardless of the type of scanner, the main magnetic field is always ON . Only in case of emergency, the scanner will be turned off. Also, unlike CT scans and x rays M.R.I does not use strong ionizing radiations.

4)The answer is false even if no patients are being scanned , one cannot bring any external metallic objects into the M.R.I scan room. There are 3 zones usually , up to zone 3 the external objects are allowed. In zone 4 where the M.R.I scan is present external metallic objects are strictly prohibited.