What can be considered a safe distance from the x-ray source during DXA scanning?

• A. 1 meter (3 feet)
• B. 2 meters (6 feet)
• C. 0.5 meters (1.5 feet)
• D. 4 meters (12 feet)

Answer: (A)

In the context of DXA (Dual-energy X-ray Absorptiometry) scanning, a safe distance from the x-ray source is crucial for minimizing exposure to ionizing radiation. The generally accepted safety guideline is to maintain a distance of at least 1 meter (3 feet) from the x-ray source. At this distance, the radiation exposure is significantly reduced, conforming to safety standards recommended by organizations like the American Association of Physicists in Medicine (AAPM).

The rationale behind this distance is based on the inverse square law of radiation, which states that the intensity of radiation decreases with the square of the distance from the source. Therefore, being 1 meter away effectively limits the radiation dose to personnel and patients not actively being scanned. This distance allows for a safe operational space while ensuring that those present in the vicinity are shielded from unnecessary exposure during the scanning process.

Understanding the importance of maintaining a safe distance emphasizes the responsibility of technicians to prioritize the safety of both patients and operators in a clinical setting.