Radiology Practice Test 2026 - Free Radiology Practice Questions and Study Guide

The standard energy range for diagnostic X-rays falls between 20 to 150 keV. This range is optimal for producing high-quality images while minimizing patient exposure to radiation. X-rays in this energy range are effective at penetrating body tissues and providing sufficient contrast between different types of tissues, which is critical for accurate diagnosis.

Using energy levels below 20 keV would result in insufficient penetration, leading to inadequate imaging, while levels exceeding 150 keV are generally suited for therapeutic applications rather than standard diagnostic purposes, as they may expose patients to unnecessary higher doses of radiation without providing additional imaging benefits.