Ultraviolet Lamps encompass a range of lights that produce Ultraviolet light. As these lights are used in many unrelated industries and applications, with many variables in their output, we’ve created a one-stop guide for helping you identify the best UV Lamp for you.
What is Ultraviolet?
UV is a light radiation produced by the sun, and you may know of it due to classic Australian ads that talk of its dangers to our skin. Invisible to the human eye, UV travels on a wavelength between visible light and x-rays.
The most important thing to understand when buying UV lamps is the differentiation between the UV subtypes. As ultraviolet light is on a spectrum, it has levels of intensity based off its wavelength. The shorter the wavelength, the more dangerous it is for humans – because while the earth’s atmosphere protects us from all but the long wave UV light, some lamps are made to produce a type that is extremely harmful to the eyes and skin, and shouldn’t be used unless by a professional.
Just knowing the below will help you identify if it’s the right light for you.
UVA: Longwave ultraviolet light, most commonly known as blacklight or blacklight blue in the lighting industry. These lights often use a filter material which makes the bulb appear violet. UVA is the safest of the UV spectrum.
UVB: Medium-wave, UVB is often used for reptile lights, and speciality tanning lamps.
UVC: Shortwave UV, and the most dangerous of the UV subtypes. Used for what is known as germicidal lamps, UVC disrupts DNA and can be used for a range of specialised applications, especially in sterilisation and water purification.
The most recognisable form of UV lighting, Black light and Black light Blue (BL and BLB) can be distinguished by the colour they emit.
Black Light Blue shines as a violet, purple colour, made due to the filter material of the bulb’s glass. Known as Woods glass, these appear almost black when unlit, filtering out most visible light. While not bright, BLB triggers a fluorescence in other colours, causing them to glow. This effect can be useful in a wide variety of applications, including medicine, forensics, detection of counterfeit money, and of course for decorative purposes in nightclubs.
Blacklight on the other hand ironically produces a bluer colour than Black Light Blue, and is often used in bug zappers and insect traps. This is due to insect’s ability to see UV light, attracting them. These lights don’t produce the fluorescence that BLB does, so make sure that the UV lamp you’re buying is dark in appearance and tagged with “BLB” if you require that effect.
Blacklight and black light blue lamps come in two core types: Fluorescent and Mercury Vapor. Below, we’ll go over the difference.
Normal fluorescent lamps produce light by sending an electric current through a tube containing argon and a small amount of mercury vapor. When the mercury vapours are excited, they produce UV light, which in turn causes the coating of the lamp to fluoresce or glow.
Fluorescent black light lamps work similarly, but use a phosphor on the inner tube surface which emits UVA radiation instead of visible light, and the dark blue filter coating over the tube.
As Fluorescent lamps already naturally produce more UV than any other light, they are well suited to the BLB and BL applications, and much more effective than incandescent BL and BLB lamps.
Mercury Vapor BLBs are most commonly used in clubs, concerts, and other large displays where the aim is to create a particular aesthetic through the fluorescent glow caused by the UV, aka the “glow in the dark” effect. Mercury vapor lamps are the most efficient producers of UVA, even more so then fluorescent tubes.
While these may look like ordinary tubes, Germicidal Lamps produce the far stronger UVC. They do not have the phosphor coating of BL or BLB, as this absorbs UVC. These tubes have nearly triple the UV output of ordinary fluorescent lamps.
As previously mentioned, this UV type is the most dangerous to come into contact with, and can cause temporary or even permanent blindness and skin conditions if mishandled. For this reason, germicidal lamps are used primarily for specialised areas.
The most common of these is in Ultraviolet germicidal irradiation (UVGI). This is a method of disinfection that uses UVC to break down and destroy bacteria and other microorganisms at a cellular level. You may see now why it can be so harmful to humans as well. Most often used to purify drinking water, as well as medical equipment and even food.