Historically, most germicidal UV light was produced by mercury vapor bulbs, emitting germicidal UV-C at a wavelength near 254 nanometers  (nm).

Over time, new UV technologies have emerged, including pulsed xenon bulbs and UV-C LEDs.

Most recently, the UV disinfection market has seen an emergence of UV excimer lamps, which produce UV-C light at shorter wavelengths, near 220 nm. The term “excimer” comes from the manner in which the UV is produced, an “excited dimer,” which is essentially a diatomic molecule. When these molecules transition from an excited state to a ground state spontaneously, they emit high-intensity ultraviolet light.

Excimer lamps  utilize noble gases such as xenon and krypton, rather than mercury. This carries certain environmental and disposal processing advantages.

Excimer lamps have already found use in medicine, treating skin conditions like vitiligo, psoriasis, and eczema. UV excimer lamps also reduce inflammation, promote repigmentation, and stimulate tissue regeneration.

Like other UV-C lamps, UV excimer lamps are useful in disinfection processes, helping to eliminate harmful pathogens in healthcare facilities, laboratories, public spaces, and water treatment plants.

One of the more interesting properties of UV-excimer lamps is their supposed low human toxicity and improved compatibility with common inanimate materials. These potential benefits are being actively studied and Microchem has been reviewing the research with great interest. As a general principle, the higher-energy photons from UV excimer bulbs are thought to penetrate just the top-most surface of living creatures, which is bad for tiny bacteria and viruses, but less harmful for humans since we’re covered in dead skin skin cells and fluids such as tears.

For information about UV testing, please contact our lab at [email protected].