Apparatus, method, and system for selectively effecting and/or killing bacteria

A method for selectively killing or destroying at least one bacteria at a medical treatment site or in a medical treatment environment, comprising:

• generating, with at least one excilamp, at least one bactericidal radiation configured to selectively kill or destroy the at least one bacteria on or within a body, while avoiding harm to cells of the body, wherein the at least one bactericidal radiation has at least one wavelength that is in a range of 190 nanometers (nm) to 230 nm, and wherein a peak wavelength of the at least one bactericidal radiation is at least one of approximately at 207 nm or approximately at 222 nm;
• filtering, with a filter arrangement comprising at least one of a band pass filter or a combination of a low pass filter and a high pass filter, the at least one bactericidal radiation to prevent all ultraviolet wavelengths that are outside of the range from passing through the filter arrangement;
• allowing all wavelengths in the range of 190 nm to 230 nm to be provided to the body;
• fluorescing visible light to indicate that the at least one excilamp is operating;
• and
• irradiating the at least one bacteria using the allowed wavelengths and selectively killing or destroying the at least one bacteria.