Clover Learning X-ray Production and Safety Practice Test 2026 - Free X-ray Safety Practice Questions and Study Guide

The key idea is that HVL increases as photon energy increases. Higher kVp means a beam has more energetic photons, which penetrate material more readily. Since HVL is the thickness of material needed to cut the beam’s intensity by half, higher-energy photons require a thicker shield to achieve that same 50% attenuation. Among the given beams, the 110 kVp beam has the highest energy, so it needs the thickest HVL. The lower-energy beams (80–100 kVp) are more readily attenuated and thus have smaller HVLs.