Radiography

Which of the following is a principle associated with radiation safety?

• ALARA

• COSHH

• HASAWA

• IRR

Protective clothing contains lead. What is the MINIMUM acceptable thickness for this lead?

• 0.15mm

• 0.25mm

• 0.35mm

• 0.45mm

X-rays travel in waves...

• True

• False

Tags

NGSS.HS-PS4-1

NGSS.HS-PS4-3

You can set the mA on your x-ray machine. What does this control?

• The penetrating power of the primary beam

• The quantity of electrons produced

• How the x-ray photons interact with patient tissues

What colour will this MOST dense material show up on an x-ray?

• White

• Dark grey

• Pale grey

• Black

Tags

NGSS.MS-PS4-2

What is the maximum permissible dose (MPD) for an adult per year?

• 5mSv / year

• 10mSv / year

• 15mSv / year

• 20mSv / year

A higher kilovoltage produces x-rays with:

• greater energy levels

• shorter wavelengths

• more penetrating ability

• all of the above

Answer explanation

An increase in kilovoltage increases the quality of the beam. It will demonstrate greater energy and shorter, more penetrating wavelengths.

Tags

NGSS.HS-PS4-1

In dental imaging, the quality of the x-ray beam is controlled by

• kilovoltage

• milliamperage

• exposure time

• source to receptor distance

Tags

NGSS.HS-PS4-3

Identify the kilovoltage range for current dental x-ray machines.

• 50-60 kV

• 60-70 kV

• 70-100 kV

• greater than 100 kV

Answer explanation

The average range for most dental x-ray machines is 65-100kV. Lower settings may not penetrate the tissue adequately and cause high contrast images; higher settings increase the radiation the patient receives and cause low contrast images.

Tags

NGSS.HS-PS4-3

Identify the unit of measurement used to describe the amount of electric current flowing through the x-ray tube

• volt

• ampere

• kilovoltage

• force