Germicidal UV-C technology
UV-C radiation is a single part of the Ultraviolet located in the lowest portion of the spectrum between 100 and 280nm. It is also generated by the sun but is filtered by the stratosphere and therefore cannot reach the earth’s surface.
The only way to get it on earth is to artificially generate it through lamps and sources of different types.
Some UV-C frequencies act on the DNA of cells and are the most effective for breaking down micro-organisms such as bacteria, mold and viruses.
The Figure represents the typical DNA absorption curve. DNA has a maximum absorption at 260-270nm, absorption ends at 300nm. Most microorganisms are more sensitive to the wavelength around 260nm.
The sources of UV-C radiation currently available on the market are:
- UV-C low pressure lamps 253.7nm
- UV-C medium pressure lamps
- UV-LED lamps 255-280nm
- Excimer lamps 222nm
The 253.7nm low pressure and medium pressure UV-C lamps are the most widespread on the global market today, they have the highest electrical efficiency and are the most reliable.
These frequencies act directly on the DNA of micro-organism cells by genetically modifying them. The most effective frequencies are those superimposed on the DNA absorption curve
When the micro-organism is exposed to UV-C radiation, this crosses the cell walls, enters the molecular structure of DNA and genetically alters it, so its ability to infect and multiply is arrested.
It is important to know that each type of micro-organism needs a certain dose of UV-C to be destroyed. This means that some micro-organisms are more resistant than others to UV-C radiation. The “dose” is represented by the amount of radiation distributed in an exposure time.