Stock image of a partly cloudy sky with visible sun rays
Stock image of a partly cloudy sky with visible sun rays

Not all rays are made equal - The ABC of UV light

By Trent

Ultraviolet (UV) light generally refers to forms of electromagnetic radiation with wavelengths between 100-400 nanometers, which are invisible to the human eye. While many people may be familiar with the term UV, they may not realize that there are several subtypes of UV radiation, each with different characteristics and effects on organic cells. 

Illustration of the light spectrum showing the wavelengths of various kinds of UV light

UV light ranges in wavelength from around 100-400 nanometers


This form of UV light has wavelengths between 315-400 nanometers and represents 95% of the UV radiation reaching earth from the sun. UV-A is the weakest form of UV radiation and does not have any disinfectant properties. UV-A is responsible for tanning and initial sunburn in humans and is therefore the light most commonly used in tanning beds and can also be found in black lights.


With wavelengths between 280-315 nanometers, this form of UV radiation is stronger than UV-A, more damaging to human DNA and is the primary cause of skin cancer from sun exposure. It is UV-B rays which cause the majority of sunburn, particularly that which appears in the hours following exposure to the sun, and the primary purpose of applying sunscreen is to prevent UV-B rays from being absorbed by the skin. UV-B radiation does not have any disinfectant properties.


UV-C radiation has the shortest wavelengths and is therefore the most powerful and damaging to organic cells. This type of radiation does not reach the earth from the sun and therefore must be created artificially. UV-C light has been used for industrial sanitization and disinfection purposes for many years and can be emitted by UV bulbs or LEDs. UV-C rays destroy the reproductive properties of a cell's DNA, which in the case of bacteria and viruses means that the cell is unable to multiply and cause infection. It is this destructive property which makes them particularly useful for disinfection and sanitization, but also makes it harmful to human tissue such as eyes and skin, causing burns, ulcers, and other wounds and therefore requires safety precautions to be taken when using for disinfection purposes.

Moshi's brand new Deep Purple foldable UV sanitizer uses UV-C rays to clean and sanitize your personal belongings, keeping them free from harmful germs and bacteria. Deep Purple offers a 360° clean in just 4 minutes using long-lasting UV LED lights and includes dual safety mechanisms to ensure no harm to the user. It is available to back now

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