BSCs: UV Lights

Many BSCs are equipped with ultraviolet (UV) lights as a form of decontaminant and should not be used as the sole disinfection method in the BSC. However, if good practices are followed, UV lights are not needed to protect tissue culture or other work from contamination. UV radiation should not take the place of wiping down the cabinet interior with a suitable disinfectant or the practice of good aseptic technique. If you wish to use UV lamps, acquaint yourself with their limitations and hazards:

  • UV light is effective only when it directly hits a microbial cell. UV light is ineffective when the target material is encased in organic matter. Also, UV lamps must be cleaned regularly to remove any dust and dirt that may block its germicidal effectiveness. Turn off the light and wipe it with 70% ethanol every two weeks.
  • Lights need to be replaced periodically. The length of time a lamp will be effective depends on the number of hours it is in use. Lamps should be checked periodically with a meter to ensure that the appropriate intensity of UV light is being emitted.
  • UV light does not penetrate cracks or seams, so it will not disinfect the spill area under the work surface.
  • Due to mercury content, UV lights need to be disposed of as hazardous waste.
  • UV exposure can burn corneas and cause skin cancer; therefore, the UV light must be turned off when the room is occupied.
  • Be aware that UV lights can cause gas line tubing to deteriorate and present a gas leak hazard.