However, biosafety cabinet UV lights have limitations that all researchers should know about before relying on them for protection against contamination. Here are three of the most common pitfalls.
You should not rely on a biosafety cabinet UV light as the sole decontaminating agent. Surface disinfection should be performed before and after every cabinet use. There are several reasons for this.First, UV light can only destroy microorganisms that it can reach, and whether a microorganism is exposed to UV light depends on several factors. For example, some biosafety cabinets are made with welds or seams where microorganisms can hide from UV light. Even the flat surfaces inside a biosafety cabinet are not perfectly flat at the microscopic level. This unevenness creates “microshadows” where microorganisms can stay safely tucked away. Additionally, microorganisms can hide behind dust or other particulates. And finally, any dust or dirt that has accumulated on the bulb itself will block UV light, and the bulb should be cleaned regularly.
The bulb of a biosafety cabinet UV light loses effectiveness over time and needs to be replaced regularly. When the intensity drops below a certain level, the percentage of microorganisms it is able to destroy drops too, leaving research products and personnel vulnerable to contamination
It’s not always easy to tell when it’s time to change the bulb. The light stays on long after its germicidal effectiveness has ceased. So how long does a biosafety cabinet UV light last? Manufacturers have developed lamp life ratings for their products, which vary depending on the type of UV light. Following these ratings will help you determine when it’s time to change the bulb.
UV light not only kills microorganisms in the biosafety cabinet, but it also destroys living cells in your body. In particular, it can cause painful damage to both your skin and your eyes, even after its intensity drops below the effective level. What’s more, the surface inside a biosafety cabinet can reflect UV light into the lab, putting personnel at risk. The safest way to use a UV light is to close the cabinet sash and leave the lab.
The best biosafety cabinets have built-in features to protect cabinet users from UV radiation by ensuring that the light is used properly. For example, in a SterilGARD, the UV/germicidal light switch and cabinet lighting can not be turned on simultaneously. Additionally, UV interlock switch assures that UV illumination occurs only when the sash is fully closed.