What is the minimum required aluminum (Al) filtration in radiographic tubes operating over 70 kilo volts peak (kVp)?

In radiographic tubes operating above 70 kilovolts peak (kVp), the minimum required aluminum filtration is 2.5 mm. This standard is established to ensure adequate filtration of the x-ray beam, which helps reduce patient radiation exposure while allowing sufficient image quality for diagnostic purposes.

Aluminum filtration serves to remove low-energy x-rays from the beam that do not contribute to image formation; these lower-energy photons are absorbed by the patient's tissue and increase the overall radiation dose without improving diagnostic information. By implementing a minimum of 2.5 mm of aluminum filtration, the radiographic systems can effectively reduce unnecessary exposure and improve the quality of the imaging.

This regulation reflects a balance between optimizing image quality for clinical needs and minimizing radiation risk to the patient, aligning with best practices in radiation safety.