What type of radiation detection instrument is used to check the milliamperage (mA) and kilovoltage peak (kVp) accuracy of an x-ray machine?

• A. Environmental survey device
• B. Equipment survey device
• C. Personal dosimetry device
• D. Occupational dosimetry device

Answer: (B)

The main idea is to verify the imaging system’s performance by testing its actual output against what the console shows. An equipment survey device is used for this purpose because it’s designed to assess the X-ray generator and beam characteristics, including the exposure factors that drive image quality and patient dose. Milliamperage controls the tube current and therefore the number of photons produced, while kilovoltage peak sets the energy and penetrating power of those photons. If mA or kVp are off, images can be under- or over-exposed and patient dose can change unexpectedly. The equipment survey instrument measures the actual exposure under controlled conditions (often with a phantom) and compares it to the machine’s indicated value, ensuring the settings are accurate and consistent over time. In contrast, environmental survey devices measure room radiation levels, and dosimetry devices worn by staff monitor occupational dose rather than machine performance.