A ceiling-mounted far-ultraviolet-C light technology reduces methicillin-resistant <i>Staphylococcus aureus</i> contamination on surfaces in a simulated operating room

To the Editor-Cleaning and disinfection of operating room (OR) surfaces is generally recognized as an important practice, [1][2][3][4] although the impact on patient outcomes is uncertain. 5A recent systematic scoping review concluded that the existing literature shows suboptimal compliance and inconsistent effectiveness of OR cleaning and disinfection. 5Ultraviolet-C (UV-C) light room decontamination devices have been shown to reduce surface contamination when operated as an adjunct to manual cleaning and disinfection. 6However, use of these devices can require a substantial amount of time and the devices can only be operated when people are not present. 6Far-UV-C light (200-230 nm) is an alternative technology that may provide similar efficacy while being safe in occupied areas. 7Here, we evaluated the efficacy of a commercial, ceiling-mounted far-UV-C technology for continuous adjunctive decontamination of surfaces in a simulated OR.The Visium 1 far-UV-C technology (Lit Thinking, Orlando, Florida) that was tested uses a krypton-chloride excimer lamp (Care222, Ushio America, Cypress, California) that emits a primary wavelength of 222 nm.We tested the Clear Optics version of Visium 1 which emits light over 60-degree angles.With Clear Optics devices placed a minimum of 1.2 m (3.9 ft) apart and operating continuously at a height of 2.5 m (8.2 ft), far-UV-C doses are within threshold limit values proposed by the American Conference of Governmental Industrial Hygienists (ie, 161 mJ/cm 2 for eyes and 479 mJ/cm 2 for skin) over an 8-hour workday. 7Users can also choose an "occupied off" mode in which the device runs continuously but turns off when motion is detected, thereby providing decontamination between cases with no far-UV-C exposure to personnel.Each device is intended to provide far-UV-C coverage for an area up to 18.6 m 2 square meters (200 ft 2 ); multiple devices can be installed to provide coverage for larger rooms.The supplementary material provides detailed information on the technology and shows results of initial laboratory testing demonstrating efficacy of a single device against methicillin-resistant Staphylococcus aureus (MRSA) with 2 and 8 h exposure times.