American Society for Nondestructive Testing (ASNT) Radiographic Testing Practice Test

Increasing the tube current is the best way to enhance the intensity of radiation produced by an x-ray tube. Tube current, measured in milliamperes (mA), directly corresponds to the number of electrons that flow from the cathode to the anode during x-ray generation. A higher tube current results in a greater quantity of x-rays being produced, thereby increasing the radiation intensity.

While increasing tube voltage can also contribute to increased intensity by boosting the energy of the x-ray photons, it primarily affects the quality or penetrating power of the x-ray beam rather than the quantity. Exposure time is the duration for which the x-ray is applied, and while extending this time does increase the total radiation exposure, it is not a direct control of the radiation intensity in terms of instantaneous output. Film sensitivity refers to the responsiveness of the film to radiation and does not directly influence how much radiation is generated by the tube itself.

Thus, for the purpose of increasing radiation intensity during the operation of an x-ray tube, increasing the tube current is the most effective method.