Final answer:
Electromagnetic radiation with wavelengths C. less than 300 nm, such as ultraviolet (UV) light, is microbicidal because it can induce DNA mutations that kill microorganisms.
Step-by-step explanation:
The wavelengths of electromagnetic radiation that possess sufficient energy to be microbicidal are those that are less than 300 nanometers (nm). This includes ultraviolet (UV) light, which ranges from 10 to 400 nm, with germicidal lamps typically emitting UV light at a wavelength of 260 nm. UV light is effective in controlling microbial growth because it can cause thymine dimers to form in DNA, leading to mutations that can kill microorganisms. However, UV light does not penetrate surfaces and must directly expose the cells.
Microbicidal electromagnetic radiation refers to electromagnetic waves that possess enough energy to kill microorganisms. The wavelengths of electromagnetic radiation that are microbicidal are typically in the range of ultraviolet (UV) light, which has wavelengths less than 300 nm.
UV light carries more energy than visible light and can break bonds at the cellular level. This high energy can lead to damage in microbial DNA, causing mutations and ultimately killing the microorganisms.
Examples of UV light sources that are commonly used for disinfection include germicidal lamps emitting UV light at a wavelength of 260 nm. UV lamps are used in water purification systems, surgical suites, and biological safety cabinets.