UV equipment, which employs ultraviolet light for a variety of purposes, is used in several types of industrial and home applications. Disinfection is probably the most common use of UV light, but it is also used for other reasons, such as viewing DNA or RNA and curing inks. While this light has many uses, it can also be harmful to skin and eyes, so appropriate safety precautions must be taken when using UV equipment.
Disinfection with ultraviolet light may be used on water, air, and surfaces. Many wastewater and drinking water treatment plants use UV lamps as the final treatment step to remove potentially harmful microbes from the water. Handheld UV drinking water treatment devices are also available for travelers and backpackers who need to purify their own water.
Air may also be purified using UV equipment. A UV bulb is used to kill germs in the air as it flows through an air purifier. Ultraviolet light is seldom used as the sole method of air purification, however, as it cannot remove dust and pollen from the air.
Small UV devices can be used for disinfection purposes in homes and while traveling. For example, there are several devices designed specifically to use UV light to disinfect toothbrushes. More general-purpose, hand-held UV sanitizers can be used on a variety of surfaces, and may be useful for travelers who are concerned about germs.
Microbiology laboratories can use UV equipment for multiple purposes. Laminar flow hoods and biosafety cabinets, for instance, generally have UV lamps installed to use for disinfection. UV is also used in blotting techniques, where it is used to attach DNA fragments to a membrane so that they may be identified.
Ultraviolet light is also used to view the nucleic acids DNA and RNA. To do this, DNA or RNA fragments are amplified, meaning that they are reproduced many times so that there is a large enough amount to work with, and stained with either ethidium bromide or Sybr green. These chemicals then react with UV light, causing the transparent nucleic acids to become more visible.
Another use of UV lamps is for curing screen prints. Special inks are available for screen printing which can be cured using UV light rather than a solvent. Solvent curing produces a large amount of pollutants known as volatile organic compounds (VOCs), and UV curing can eliminate health concerns surrounding these. UV curing is also faster than solvent curing, although it is not appropriate for all screen printing applications.
Anyone working with any type of UV equipment should be sure to protect their eyes from the ultraviolet light. This may be accomplished by wearing protective glasses or shielding the lamps. Skin should also be protected when using lamps with strong UV intensities.