Low Energy X-rays (LEXRs)
The nature of Low Energy X-rays (LEXRs) or “Soft" X-rays differ from High Energy X-rays in a few important ways. X-rays may be produced in a range of energy levels from tens of electron volts (eV) to 5 thousand KeV (or 5 MeV). In general, there is a direct correlation between the transmission of sterilizing energy and the absorption of sterilizing energy by the products being sterilized; however in a certain range of low energy levels, when the target to be irradiated is close to the emission source, the absorption rate of the material being exposed increases rather than decreases, which enables the sterilization of individual products with a high degree of efficiency.
The illustration of the relative efficacy of LEXR vs HEXR can be seen from the V-curve (shown below) which shows the relationship between absorption energy (Y-axis) and transmission energy (X-axis).