High humidity in large kitchens and refrigeration rooms can be ensured against indoor climate challenges with UVC lamps.

In connection with the operation of refrigeration rooms with production at Slagelse Hospital, there was a need for measures that could help ensure against problems due to the high humidity in the room. Various measures had been taken, such as increased ventilation and cleaning. Additionally, there was a desire to supplement with a UVC system that covered the room and the front of the evaporators. By operating once a day, the UVC lamps ensure a reset of the room against the development of microorganisms before staff arrive and normal operations begin. 


Since it is a cold room below 12°C, UVC lamps that light up and work well in cold and humid conditions have been chosen. Regular UVC lamps lose effectiveness when operating at temperatures below 15°C. 

The UVC lamps were installed in a customized holder that ensures a good distance to the ceiling but provides 360° lighting, so the light is used as efficiently as possible. The lamps were placed to provide as uniform coverage of the room/tables/ floor as possible, considering ventilation, installations, etc. in the ceiling. 


The control of the lamps was adapted so that the building’s CTS system controls on/off as well as fault signals from the system. Safety around UVC was ensured primarily through nighttime operation, light, and sound alarms before UVC ignition, and strategically placed process stops and break contacts on all doors. 

Calibration of the system was done based on measurements in connection with the project handover (SAT). The final ignition time for the UVC lamps was set at 35 minutes, where the calculated starting point was 40 minutes. Therefore, UVC systems must always be checked under normal operating conditions in the actual situation. In this situation, the actual ignition time was shorter than expected, which is positive and shows that the calculations are accurate.