UV Lamp
UV or ultraviolet lamps are used in biological safety cabinets, light boxes, and crosslinkers in several University laboratories and in some patient care rooms. One of the problems in working with UV radiation is that the symptoms of overexposure are not immediately felt so that persons exposed don’t realize the hazard until after the damage is done. Ultraviolet radiation is that radiation just outside the visible range, or under 400 nanometers (nm).
UV irradiation of the work area should only be used as a secondary method of maintaining the sterile status of a cabinet: it should never be relied on alone to disinfect an impure work area. UV light is ineffective if dust, dirt, or organic matter protects a microbial cell. A liquid chemical disinfectant should be the main method of cleaning and disinfecting the interior of a BSC. 70% ethanol is not considered an effective disinfectant for hard surfaces in the BSC. UV light doesn’t penetrate into cracks or through the grillwork of a BSC. The spill area under the work surface of a BSC is a favorite hide out for fungal spore and resilient bacteria. The intensity of the UV lamp is affected by the accumulation of dirt and dust on its surface. Don’t touch a UV bulb with your bare hands. The natural oils on your hand may leave a fingerprint and generate dead space on the bulb’s surface. UV bulbs have to be cleaned frequently by turning off the UV light and wiping off the surface of the room temperature bulb with 70% alcohol. The fan has to be off and the sash has to be closed, if possible, when the UV light is on.
The eyes are susceptible to UV damage. Like the skin, the covering of the eye or the cornea is epithelial hankie, too. The risk to the eye is enhanced by the fact that light can enter from all angles around the eye and not only in the direction you are looking. The lens can also be injured, but since the cornea acts as a filter, the chances are reduced. It should not lessen the concern over lens damage however, because cataracts are the direct result of lens damage. Burns to the eyes are generally more painful and serious than a burn to the skin. Make sure your eye protection is suitable for this work. There are particularly made safety glasses for the different UV ranges. You should not forget to protect the rest of your face, too. Severe skin burns can happen in a very short time, particularly under your chin (where most people forget to cover). Full-face shields are truly the only appropriate protection when working with UV light boxes for more than a few seconds.