Calculation of air-kerma rate of diagnostic X-ray generators.

As one type of basic physical data related to the calculation of the construction of X-ray examination room shielding, we investigated the air-kerma rate 1 m from the source of the useful beam focus per unit current time product. Compared to the X-ray energy penetration values obtained in prior research, we obtained higher values. We found three causes for this discrepancy: (1) the X-ray tube total filtration (increasing total filtration reduces air kerma), (2) the tube voltage ripple percentage (increased voltage ripple reduces air kerma, and (3) the target angle (increasing the target angle increases the air kerma). On standardizing (1)-(3), we confirmed that our values mostly matched those obtained in past research. Consequently, when one employs the air-kerma rate that results from the consideration of (1)-(3), without pursuing a path of excessive safety, calculation of shielding under clinical conditions is possible.