Filtration eliminates low-energy x-rays, thus reducing patient exposure.

• A. True
• B. False
• C. It increases exposure
• D. It has no effect

Answer: (B)

Filtration removes the low-energy photons from the X-ray beam. Those low-energy photons are more likely to be absorbed by superficial tissues like skin and soft tissue, contributing to patient dose without helping form a better image. By filtering them out, the beam becomes harder (higher average energy), which reduces the dose delivered to the patient for the same image receptor exposure and can even improve image contrast. In practice, because filtration also lowers the total number of photons reaching the patient, clinicians may adjust exposure settings to maintain the desired image density. So, filtration does eliminate low-energy X-rays and reduces patient exposure.