Figure 2-5. The higher the kVp, the deeper the penetration of the X-ray into the film, the
greater the quantity of diagnostic X-rays.
kilovolt: unit of electromotive force equal
to 1,000 volts of electricity.
voltage: the electrical pressure that causes electrons to move; measured in volts.
kilovoltage peak (kVp): the very highest voltage occurring at any time during an
electrical cycle; the peak kilovoltage used in making an X-ray exposure.
(3) Set Bucky, if applicable. Once you have set the technique factors for
mAs and kVp, you are ready to make the non-Bucky/Bucky selection, which is
determined by the thickness of the body part to be radiographed. If the Potter-Bucky
diaphragm (Bucky) is to be used for the examination, a switch marked Bucky can be
activated. The Bucky is a sliding tray like device found just below the table on which a
patient lies during the X-ray examination. The film is placed inside the Bucky tray and
held in place by a pair of jaws that center the film under the midline of the table once the
tray is pushed firmly closed (figures 2-6 and 2-7).