Researchers at the University of Nebraska Medical Center have recently published an article in the Journal of Occupational and Environmental Hygiene demonstrating the benefits of Lumacept UV-C reflective coatings. This study was conducted in the Nebraska Biocontainment Unit, which is one of only a few units in the US capable of treating patients with deadly infectious diseases such as Ebola. In this study, researchers used a portable UV device to inactivate MRSA and VRE and found that “coating hospital room walls with UV-reflective paint enhanced UVGI disinfection of nosocomial bacteria on various surfaces compared to standard paint, particularly at a surface placement site indirectly exposed to UVC light.”
Ultraviolet (UV)-reflective paint with ultraviolet germicidal irradiation (UVGI) improves decontamination of nosocomial bacteria on hospital room surfaces.
An ultraviolet germicidal irradiation (UVGI) generator (the TORCH, ClorDiSys Solutions, Inc.) was used to compare the disinfection of surface coupons (plastic from a bedrail, stainless steel, and chrome-plated light switch cover) in a hospital room with walls coated with ultraviolet (UV)-reflective paint (Lumacept) or standard paint. Each surface coupon was inoculated with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus faecalis (VRE), placed at 6 different sites within a hospital room coated with UV-reflective paint or standard paint, and treated by 10 min UVC exposure (UVC dose of 0-688 mJ/cm2 between sites with standard paint and 0-553 mJ/cm2 with UV-reflective paint) in 8 total trials. Aggregated MRSA concentrations on plastic bedrail surface coupons were reduced on average by 3.0 log10 (1.8 log10 Geometric Standard Deviation [GSD]) with standard paint and 4.3 log10 (1.3 log10 GSD) with UV-reflective paint (p = 0.0005) with no significant reduction differences between paints on stainless steel and chrome. Average VRE concentrations were reduced by ≥4.9 log10 (<1.2 log10 GSD) on all surface types with UV-reflective paint and ≤4.1 log10 (<1.7 log10 GSD) with standard paint (p < 0.05). At 5 aggregated sites directly exposed to UVC light, MRSA concentrations on average were reduced by 5.2 log10 (1.4 log10 GSD) with standard paint and 5.1 log10 (1.2 log10 GSD) with UV-reflective paint (p = 0.017) and VRE by 4.4 log10 (1.4 log10 GSD) with standard paint and 5.3 log10 (1.1 log10 GSD) with UV-reflective paint (p < 0.0001). At one indirectly exposed site on the opposite side of the hospital bed from the UVGI generator, MRSA concentrations on average were reduced by 1.3 log10 (1.7 log10 GSD) with standard paint and 4.7 log10 (1.3 log10 GSD) with UV-reflective paint (p < 0.0001) and VRE by 1.2 log10 (1.5 log10 GSD) with standard paint and 4.6 log10 (1.1 log10 GSD) with UV-reflective paint (p < 0.0001). Coating hospital room walls with UV-reflective paint enhanced UVGI disinfection of nosocomial bacteria on various surfaces compared to standard paint, particularly at a surface placement site indirectly exposed to UVC light.
In an article recently published in the Journal of Occupational and Environmental Hygiene, researchers at the CDC’s National Institute of Occupational Health and Safety studied the use of UVGI in an ambulance. The study found that optimizing the location of the UV fixtures and using Lumacept UV-C reflective paint “can substantially improve the performance of a UVGI system and reduce the time required for disinfection”. These finding are in excellent agreement with our previous trials of Lumacept in hospital rooms.
J Occup Environ Hyg. 2017 Oct 23:0. doi: 10.1080/15459624.2017.1376067.
Ambulance disinfection using Ultraviolet Germicidal Irradiation (UVGI): Effects of fixture location and surface reflectivity.
Ambulances are frequently contaminated with infectious microorganisms shed by patients during transport that can be transferred to subsequent patients and emergency medical service workers. Manual decontamination is tedious and time-consuming, and persistent contamination is common even after cleaning. Ultraviolet germicidal irradiation (UVGI) has been proposed as a terminal disinfection method for ambulance patient compartments. However, no published studies have tested the use of UVGI in ambulances. The objectives of this study were to investigate the efficacy of a UVGI system in an ambulance patient compartment and to examine the impact of UVGI fixture position and the UV reflectivity of interior surfaces on the time required for disinfection. A UVGI fixture was placed in the front, middle or back of an ambulance patient compartment, and the UV irradiance was measured at 49 locations. Aluminum sheets and UV-reflective paint were added to examine the effects of increasing surface reflectivity on disinfection time. Disinfection tests were conducted using Bacillus subtilis spores as a surrogate for pathogens. Our results showed that the UV irradiance varied considerably depending upon the surface location. For example, with the UVGI fixture in the back position and without the addition of UV-reflective surfaces, the most irradiated location received a dose of UVGI sufficient for disinfection in 16 seconds, but the least irradiated location required 15 hours. Because the overall time required to disinfect all of the interior surfaces is determined by the time required to disinfect the surfaces receiving the lowest irradiation levels, the patient compartment disinfection times for different UVGI configurations ranged from 16.5 hours to 59 minutes depending upon the UVGI fixture position and the interior surface reflectivity. These results indicate that UVGI systems can reduce microbial surface contamination in ambulance compartments, but the systems must be rigorously validated before deployment. Optimizing the UVGI fixture position and increasing the UV reflectivity of the interior surfaces can substantially improve the performance of a UVGI system and reduce the time required for disinfection.
A recent study has confirmed that Lumacept can significantly improve UV disinfection effectiveness.
Rutala, W.A., Gergen, M.F., Tande, B.M., Weber, D.J. Room decontamination using an ultraviolet-C device with short ultraviolet exposure time (2014) Infection Control and Hospital Epidemiology, 35 (8), pp. 1070-1072.
Click here to read the abstract
A study was conducted at the University of North Carolina to compare the effectiveness of a UV disinfection device both with and without the presence of UV-reflective wall coatings. This study used a portable UV device with a fixed cycle time, which can be adjusted based on the size of the room and the microorganism to be targeted. In this study, samples of MRSA and C. diff. were placed in ten locations throughout the room. These locations consisted of touchable surfaces and included some surfaces that were directly illuminated by the device as well as other surfaces that were in shadowed areas. The device was operated for 5 minutes during MRSA trials and for 10 minutes during C. diff. trials.
The results demonstrate that Lumacept significantly improves UV disinfection in hospital rooms, both for MRSA and C. diff. This improvement is most apparent in those areas of a room that do not get directly illuminated by the device. Because most objects in a hospital room strongly absorb UV, there are many surfaces that do not receive a full dose of UV. Lumacept helps eliminate shadows, making the disinfection process more uniform and effective.
A study conducted at the University of North Carolina has demonstrated that Lumacept can reduce disinfection times by 80%.
Rutala, W.A., Gergen, M.F., Tande, B.M., Weber, D.J. Rapid hospital room decontamination using ultraviolet (UV) light with a nanostructured UV-reflective wall coating (2013) Infection Control and Hospital Epidemiology, 34 (5 SPL), pp. 527-529.
Click here to view the abstract
A study was conducted to test the effect of UV-reflective coatings on the disinfection time and effectiveness of a sensor-based portable UV device. The study included samples of two microorganisms, MRSA and C. diff., which were placed in ten locations throughout a standard patient room. The UV device was positioned at the foot of the bed and was operated remotely. The device uses sensors to measure the amount of light reflected back to the device. These measurements are used to automatically adjust the cycle time of the device, depending on the target microorganism. Samples in all ten locations were tested both before and after the room was painted with Lumacept UV-reflective wall coating.
The results of the study were that Lumacept reduced the cycle time of the device by 80%. During MRSA trials, the cycle time was reduced from 25 minutes to 5 minutes. For C. diff., the cycle time was reduced from 44 minutes to 9 minutes. Further, the microbiological samples confirmed that there was no loss of effectiveness, despite the dramatically reduced cycle time. In fact, in indirect areas (those not directly illuminated by the device) there was an increase in log-reduction.
A study demonstrating the effectiveness of LumaSim for predicting UV irradiance in healthcare facilities was presented at the APIC 2014 Conference in Anaheim, CA.
The study was conducted in two locations. An initial proof-of-concept study was performed at the University of North Carolina in the same rooms used in previous studies of Lumacept. UV-C irradiance measurements were taken in 10 locations throughout the room. Measurements were taken both with and without the presence of Lumacept-painted walls. A 3D model of the room was constructed and LumaSim was used to predict the intensity of UV-C in these locations. Good agreement was found between the measured and predicted values. Below is a rendering from the 3D model for the room containing UV-reflective walls.
A second, more detailed, study was then conducted at Sanford South University Hospital in Fargo, ND. This study included measurements of 20 high-touch surfaces. In addition, 5 different device locations were studied and the UV-reflectivity of the walls was adjusted by painting the room with various grades of Lumacept. Control measurements were also taken in the room using traditional non-UV-reflective paint. The image below shows the locations of several of these target surfaces (red) and the locations of the device (blue):
The results were as follows:
- Over a very wide range of UV intensities, LumaSim demonstrated excellent predictive capabilities. For more details, download the APIC Presentation.
- The effect of device location is pronounced. The total time necessary to achieve a targeted dose depended heavily on the location of the surface relative to the location of the device. This highlights the need to select device locations carefully.
- The effect of Lumacept was to significantly increase the overall level of UV intensity, especially for surfaces not in direct line of sight of the device. Further, Lumacept greatly reduced the amount of time necessary to achieve a target dose on all surfaces.
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