Prevost E. (October 1983). "The rise and fall of fluorescent tinea capitis". Pediatr Dermatol. 1 (2): 127–33. doi: 10.1111/j.1525-1470.1983.tb01103.x. PMID 6680181. S2CID 42087839. Morales-Trujillo M. L.; Arenas R.; Arroyo S. (July 2008). "[Interdigital erythrasma: clinical, epidemiologic, and microbiologic findings]". Actas Dermosifiliogr (in Spanish). 99 (6): 469–73. doi: 10.1016/s1578-2190(08)70291-9. PMID 18558055. S2CID 22836457. [ permanent dead link] It is often referred to as ultraviolet ‘light,’ but UV is a type of electromagnetic radiation with wavelengths shorter than visible light and longer than X-rays. Fluorescent materials are also very widely used in numerous applications in molecular biology, often as "tags" which bind themselves to a substance of interest (for example, DNA), so allowing their visualization. The intensity of the light should be about average. It should not be higher than normal like a flashlight. LED

However, fluorescent UV light is still deemed to be the very best, even better than the LED version as the slightly lower wavelengths cause the objects to fluoresce more dramatically. However, there are some reasons you may want to choose another wavelength. For UV LEDs, the general rule is that the shorter the wavelength, the higher the price. 395 nm UV LEDs, for example, are a common and relatively affordable option that provides decent levels of fluorescence at a more affordable price point. Wood's lamp is useful in diagnosing conditions such as tuberous sclerosis [22] and erythrasma (caused by Corynebacterium minutissimum, see above). [23] Additionally, detection of porphyria cutanea tarda can sometimes be made when urine turns pink upon illumination with Wood's lamp. [24] Wood's lamps have also been used to differentiate hypopigmentation from depigmentation such as with vitiligo. A vitiligo patient's skin will appear yellow-green or blue under the Wood's lamp. [ citation needed] Its use in detecting melanoma has been reported. [25] See also [ edit ]All electromagnetic waves are measured in metres, but some wavelengths (like UV) are so small that they’re measured in nanometres (nm). You will often see product descriptions on Lightbulbs Direct reference the ‘nm’ range of the lamp because it directly affects what type of light bulb it is. Winter M. L.; Ellis M. D.; Snodgrass W. R. (June 1990). "Urine fluorescence using a Wood's lamp to detect the antifreeze additive sodium fluorescein: a qualitative adjunctive test in suspected ethylene glycol ingestions". Ann Emerg Med. 19 (6): 663–7. doi: 10.1016/S0196-0644(05)82472-2. PMID 2344083. LED: Some Light Emitting Diodes also allow UV light to escape the phosphor coating over the LED chips that tune the visible light. Very efficient and long lasting with little to no heat generated. For most basic applications, 1 watt of UV light energy output is sufficient to create strong fluorescence effects over a 100 sq ft area. For a 200 sq ft area, simply multiply the target UV levels by 2x for an estimated 2 watts of UV light energy needed. These lamps are used mainly for theatrical purposes and concert displays. They are more efficient UVA producers per unit of power consumption than fluorescent tubes.

One of the innovations for night and all-weather flying used by the US, UK, Japan and Germany during World War II was the use of UV interior lighting to illuminate the instrument panel, giving a safer alternative to the radium-painted instrument faces and pointers, and an intensity that could be varied easily and without visible illumination that would give away an aircraft's position. This went so far as to include the printing of charts that were marked in UV-fluorescent inks, and the provision of UV-visible pencils and slide rules such as the E6B.

We first note that the UV output for the product is 0.9 watts per foot. Based on our estimated UV light needs of 1 W per 100 sqft, we determine that we will need 2 W for our 200 sqft area (multiply by 2x).

They emit a mixture of ultraviolet and visible light and will appear to glow a luminous blue colour when operating. IMPORTANT: electrical watts does not equal UV light watts! As with regular household light bulbs (e.g. 60 Watts), we are most accustomed to describing UV light bulb power in terms of its electrical energy consumption. But as is the case with household light bulbs, what matters most is the amount of light energy produced. Finally, when choosing a UV light fixture, you should know that they can come in a variety of shapes and forms. Below, we've listed several examples and situations where they could be useful. A Wood's lamp is a diagnostic tool used in dermatology by which ultraviolet light is shone (at a wavelength of approximately 365 nanometers) onto the skin of the patient; a technician then observes any subsequent fluorescence. For example, porphyrins—associated with some skin diseases—will fluoresce pink. Though the technique for producing a source of ultraviolet light was devised by Robert Williams Wood in 1903 using " Wood's glass", it was in 1925 that the technique was used in dermatology by Margarot and Deveze for the detection of fungal infection of hair. It has many uses, both in distinguishing fluorescent conditions from other conditions and in locating the precise boundaries of the condition.The revolution of LED has successfully been applied to this incredible lighting effect, creating a higher wavelength of around the 400nm range. LED has a very long lifespan and should be your first choice wherever possible. Budget Zeman, Gary (2009). "Ultraviolet Radiation". Health Physics Society. Archived from the original on 2010-01-13. Fluorescent: Comes with various lamp base sizes for regular lamp holders as well as in tube form. Reasonably power efficient with a long lifespan. While BLB light bulbs are not hazardous to your health in the same way that germicidal UVC light bulbs are, they should always be handled with care. Wear gloves when handling them to avoid contaminating the light bulb, and ensure they are disposed of safely. Avoid long exposure where possible. What is a "watt" of UV light? Watts are simply units of energy, and as you may recall from your introductory physics classes, energy can exist in a variety of forms - for example, electrical, kinetic, chemical, or light energy. In this case, we are measuring the amount of light energy emitted in the UV wavelengths.