Field of the Invention

The present invention relates generally to light disinfection systems, more preferably to ultraviolet light disinfection systems, and to a method for disinfecting surfaces in an enclosed space. More particularly, but not exclusively, it relates to a system which uses one or more remote monitoring devices and a method for disinfecting an enclosed space using one or more remote monitoring devices.

Background to the Invention

Ultraviolet light is used for food, air and water purification as well as in the disinfection of surfaces. Ultraviolet radiation with a wavelength ranging between 280 nm and 100 nm (UV-C) is harmful to micro-organisms, such as spores, bacteria and viruses. UV-C (also known as germicidal UV), in appropriate doses, can destroy nucleic acids in micro-organisms in such a way that their DNA, RNA and proteins are disrupted by the UV-C radiation (i.e. it is mutagenic). Primarily, UV-C causes strands of DNA to fuse creating thymine dimers. This leaves micro-organisms unable to perform vital cellular functions rendering them harmless or prohibiting growth and reproduction. This use of UV-C is known as ultraviolet germicidal irradiation (UVGI).

UVGI is useful for sterilization of surfaces and some transparent objects. UV-C irradiation is used to sterilize the interiors of biosafety cabinets, ward rooms, operating theaters as well as other laboratory and healthcare environments between uses.

The effectiveness of UV-C in any environment depends on a number of factors. These include the length of time micro-organisms are exposed to the UV-C; the existence of any power fluctuations of the UV-C source that impact on its wavelength; the presence of any shaded or shielded areas in the environment, for example, as a result of objects and/or particles (e.g. dirt) in the environment that shield or shade the micro-organisms from UV-C exposure; and the ability of micro-organisms to withstand UV-C during exposure. In healthcare or hospital environments, UV-C systems are commonly used in cleaning operations to disinfect surfaces within a room. Existing disinfection systems comprise a central UV-C generating assembly which further comprises one or more mercury or xenon lamps as a source of UV-C radiation. The assembly can be placed in a room to be disinfected and subsequently activated. The lamp or lamps then irradiate the room for an amount of time deemed sufficient to disinfect the room. The effectiveness of such an assembly is dependent upon whether a line-of- sight exists between the surfaces in the room to be disinfected and the lamp or lamps of the assembly. Healthcare environments are often cluttered with objects. Such objects can create shaded regions where there is no line-of-sight between surfaces behind the objects and the assembly. In order to disinfect these shaded regions, the room would need to be irradiated for a greater amount of time as the intensity of UV-C incident upon the shaded regions is less than in regions with a direct line of sight.

Irradiating a room for a greater amount of time is often undesirable. Over exposure of surfaces in the room to UV-C can damage the surfaces. UV-C can break down chemical bonds leading to the rapid ageing of plastics as well as other materials.

There are also benefits associated with reducing the irradiation time and/or keeping it down to a minimum. Reduced irradiation time enables rooms to be made available to patients sooner. Furthermore, a reduced running time requires less energy leading to environmental and cost benefits.

As such, there is a need to provide an assembly which affords reduced irradiation time when compared to existing ultraviolet disinfection systems.

The TRU-D SmartUVC™ disinfection system monitors UV-C concentration in an environment being disinfected based on UV-C reflected back to the main emitting device. The TRU-D SmartUVC™ system monitors UV-C concentration at the point of light generation, i.e. on the top of the UV-C emitting bulbs for reflected UV-C light.

This is not very accurate as it is dependent on such things as the colour of the surfaces in the room and not the actual UV-C exposure to the surfaces.

Hence there is a need to provide a disinfection system capable of measuring the UV-C exposure at the target surfaces which are to be disinfected. Summary of the Invention

The present invention relates, in part, to a disinfection system comprising: a luminaire assembly for generating a UV-C output suitable for disinfecting a surface upon which the light is incident; a control system for controlling the light output of the luminaire assembly; and a remote monitoring device in communication with the control system, wherein, in use, the remote monitoring device generates a measured UV-C intensity based upon the intensity of the UV- C output of the luminaire assembly detected by the remote monitoring device at the location of the remote monitoring device. The light output of the luminaire assembly may be multidirectional.

The control system may be suitable for controlling the directional light output of the luminaire assembly. The control system may control the UV-C output of the luminaire assembly based upon the measured UV-C intensity.

The disinfection system may further comprise a calculating module or means, wherein the calculating module or means generates a calculated light output of the luminaire assembly required to disinfect a surface at the location of the remote monitoring device based upon the measured UV-C intensity.

The control system may control the UV-C output of the luminaire assembly based upon the calculated UV-C output. The remote monitoring device may be located remotely from the luminaire assembly. The control system may control the UV-C output of the luminaire assembly based upon the location of the remote monitoring device.

The remote monitoring device may be a plurality of remote monitoring devices and each remote monitoring device generates a measured UV-C intensity based upon the intensity of the UV-C output of the luminaire assembly detected by the remote monitoring device at the location of the remote monitoring device.

The disinfection system may further comprise a calculating module or means, wherein the calculating module or means generates calculated UV-C outputs of the luminaire assembly required to disinfect a surface at the location of each of the plurality of remote monitoring devices based upon the measured UV-C intensity generated by each of the plurality of remote monitoring devices.

The control system may control the UV-C output of the luminaire assembly based upon the calculated UV-C outputs.

The plurality of remote monitoring devices may each be located remotely from the luminaire assembly. The control system may control the UV-C output of the luminaire assembly based upon the location of each of the plurality of remote monitoring devices.

The cumulative UV-C exposure at the remote monitoring device(s) may be logged during a decontamination process.

The remote monitoring device(s) may indicate that the luminaire assembly is due for replacement if a diminished power output is detected. The control system may be in radio communication with the luminaire assembly, wherein the luminaire assembly will automatically cease generating a UV-C output should the radio communication cease. The present invention relates, in part, to a method for disinfecting surfaces within an enclosed space, the method comprising the steps of: positioning a luminaire assembly within the enclosed space; positioning a remote monitoring device within the enclosed space; measuring the intensity of a UV-C output of the luminaire assembly at the remote monitoring device; and controlling the UV-C output of the luminaire assembly based upon the measured light intensity.

The method may further comprise the steps of: performing a flash test once the luminaire assembly and remote monitoring device have been positioned; and subsequently beginning the disinfection process if the flash test is successful.

The flash test may be used to determine a likely treatment time. Brief Description of Drawings

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows an exemplary luminaire assembly which is part of a disinfection system; and Figure 2 shows an exemplary remote monitoring device which is part of the disinfection system; and

Figure 3 shows the disinfection system as it might be set out within a room. Detailed Description

The disinfection system described herein provides for a decontamination process which is significantly faster than existing systems. The disinfection system makes use of light in the UV-C band, however, it will be understood that any other electromagnetic radiation suitable for use in a disinfection system may be used in place of UV-C light.

Figure 1 shows an exemplary a luminaire or light assembly 100 which may form a part of the disinfection system described herein and which comprises a light source 101 , a base 102 upon which the light source 101 is mounted and a plurality of castors 103.

The light source 101 may be, but is not limited to being, a high intensity UV-C emitting fluorescent tube 101 a.

The light source 101 may be, but is not limited to being, multidirectional.

The light source 101 may comprise concave mirrors and or reflectors so as to focus the emitted electromagnetic radiation.

The light source 101 may be, but is not limited to being, a plurality of light sources 101a. The plurality of light sources 101 a may comprise a plurality of high intensity UV-C emitting fluorescent tube 101 a. The plurality of UV-C emitting fluorescent tubes 101 a may be arranged so as to form a cylinder like shape. For example, the UV-C emitting fluorescent tubes 101 a may be arranged about the circumference of the cylinder (as shown in Figure 1 ). In such an arrangement, UV-C light may be simultaneously emitted by each of the UV-C emitting fluorescent tubes 101 a in multiple directions such that it is incident upon a large surface area within an enclosed space. The light output of such a luminaire assembly 100 is multidirectional.

The castors 103 are disposed beneath the base 102 upon which the light source 101 is mounted. As such, the luminaire assembly 100 may easily be moved. Figure 2 shows an exemplary remote monitoring device 200 which may form a part of the disinfection system described herein. The remote monitoring device comprises a sensor 201 and a housing 202. The remote monitoring device 200 is able to provide real-time feedback of the level of the UV-C exposure that the environment in which it is placed experiences. The remote monitoring device 200 is a distinct, separate unit from the luminaire or light assembly 100. The remote monitoring device 200 can be placed on the luminaire or light assembly 100 or located remotely from the luminaire or light assembly 100.

The remote monitoring device 200 is configured to detect the electromagnetic radiation emitted by the light source 100 which is incident upon the location of the remote monitoring device 200 via the sensor 201.

The remote monitoring device 200 may further comprise a location tracking module or means for identifying its location and/or orientation relative to the luminaire assembly 100. Any suitable location tracking module or means for identifying the location and/or orientation of the remote monitoring device 200 relative to the luminaire assembly 100 may be used. Exemplary location tracking module or means include any suitable satellite navigation systems such as a global positioning system (GPS) or local positioning systems (LPS) such as realtime locating systems (RTLS), active radio frequency identification, active radio frequency identification - infrared hybrid, infrared, optical locating or any other suitable RTLS as would be understood by a person skilled in the art.

The luminaire assembly 100 may also further comprise a location tracking module or means for identifying its location and/or orientation relative to the remote monitoring device 200. Any suitable location tracking module or means, including the examples given above in relation to the remote monitoring device 200, may be used.

The remote monitoring device 200 may generate a measured UV-C intensity based upon the intensity of the UV-C output of the luminaire assembly detected by the remote monitoring device at the location of the remote monitoring device.

As such, the remote monitoring device 200 can be placed within an area which is to be disinfected and can record the intensity of UV-C incident at the location of its sensor 201. Figure 3 shows the disinfection system as it might be set out within a room 300. The disinfection system comprises the luminaire assembly 100, four remote monitoring devices 200, a control system 301 , a calculating module or means 302 and an optional remote user interface 303 placed outside the room 300.

Although four remote monitoring devices 200 are shown, any other number of devices could be used. The control system 301 may be used to control the output of the luminaire assembly 100. Where the luminaire assembly 100 is of the type shown in Figure 1 , as described above, the control system 301 may control the directional output of the luminaire assembly 100 by controlling the output of each of the individual UV-C emitting fluorescent tubes 101 a. The output of each tube 101 a may be controlled by switching the tubes 101 a on and off and/or by dimming and brightening the tubes 101a.

The remote monitoring device 200 may comprise a communication module or means for communicating with the control system 301 (not shown) and the control system 301 may comprise a communication module or means for communicating with the remote monitoring device 200. Any suitable communicating module or means may be used, as would be understood by a person skilled in the art. For example, the remote monitoring device 200 may be in a wired communication with the control system 301 or it may be in a wireless communication with the control system 301. As such, the communication module or means may comprise a fibre optic communication system, a radio communication system, a Bluetooth™ system, a Wi-Fi network or any other suitable communication module or means. If the communication between the remote monitoring device 200 and the control system 301 becomes disrupted, the luminaire assembly 100 may automatically cease generating a UV-C output.

Where the remote monitoring device 200 is in radio communication with the control system 301 , the polling frequency may be 4 seconds and may comprise a double watchdog safety mechanism. Alternatively, the control system 301 may comprise part of the remote monitoring device 200. For example, the control system 301 may be located within the housing 202 of the remote monitoring device 200.

The remote monitoring device 200 may transmit the measured UV-C intensity to the control system 301 , for example, via the communicating module or means. The control system 301 may then control the output of the luminaire assembly 100 based upon the received measured UV-C intensity.

The control system 301 may control the output of the luminaire assembly 100 based upon a known location of the remote monitoring device 200 relative to the luminaire assembly 100. The control system 301 may control the output of the luminaire assembly 100 based upon the combination of the received measured UV-C intensity and a known location of the remote monitoring device 200 relative to the luminaire assembly 100. A calculating module or means 302 may be provided which calculates, for example by using an algorithm, a required output value which represents the optimum UV-C light output of the luminaire assembly 100 required to disinfect a surface at a known location of the remote monitoring device 200 based upon the measured UV-C intensity.

For example, based upon the measured intensity, the calculating module or means 302 may calculate the length of time which the luminaire assembly 100 would need to be switched on for so as to ensure that enough UV-C light reached the known location of the remote monitoring device 200 so as to ensure that the above outlined disinfecting effects occur.

Using the required output value, the control system 301 may control the UV-C output of the luminaire assembly 100 so as to ensure that sufficient UV-C light is incident upon the location of the remote monitoring device 200 so as to disinfect any surfaces within in the area surrounding the remote monitoring device 200.

Furthermore, using the required output value, the control system 301 may control the output of the luminaire assembly 100 so as to ensure that the area surrounding the remote monitoring device 200 is not overexposed to UV-C light which may have the aforementioned damaging effects.

Where the luminaire assembly 100 is of the type shown in Figure 1 comprising multiple UV-C emitting fluorescent tubes 101 a, the known location of the remote monitoring device 200 relative to the luminaire assembly 100 may be used by the control system 301 alongside the required output value to control the directional output of the luminaire assembly 100. For example, only the UV-C emitting fluorescent tubes 101 a which are known to output UV-C light incident upon the location of the remote monitoring device 200 may be controlled based upon the required output value calculated using the measured UV-C intensity provided by the remote monitoring device 200.

Advantageously, the efficiency of the disinfection system is enhanced as a result of the above outlined controlling of the luminaire assembly 100. Reduced time of whole room decontamination is also achieved and the efficacy of the disinfection process is guaranteed by the monitoring of UV-C concentration at actual target surfaces. An optional remote user interface enables a user to control operation of the system at a location remote from an area which is being disinfected (for example, outside of a room which being disinfected).

The calculating module or means 302 may be located at one of the control system 301 , the luminaire assembly 100, the remote monitoring device 200 and the remote user interface 303.

The control system 301 may be located at one of the luminaire assembly 100, the remote monitoring device 200 and the remote user interface 303. The control system 301 may, for example, be located in the base 102 of the luminaire assembly 100.

The disinfection system may comprise multiple ones of the remote monitoring devices 200 as described above, each device 200 being in communication with the control system 301.

Each of the remote monitoring devices 200 may produce a measured UV-C intensity. As such, required output values may be calculated for each of the remote monitoring devices 200. The control system 301 may then control the output of the luminaire assembly 100 so as to ensure that sufficient UV-C light is incident upon the location of each of the remote monitoring devices 200 so as to disinfect any surfaces within in the areas surrounding each of the remote monitoring devices 200.

Where the luminaire assembly 100 is of the type shown in Figure 1 comprising multiple UV-C emitting fluorescent tubes 101a, and where the location of the remote monitoring devices 200 relative to the luminaire assembly 100 is known, the location information of each device 200 may be used by the control system 301 alongside the required output value associated with each device 200 to control the directional output of the luminaire assembly 100. For example, only the UV-C emitting fluorescent tubes 101 a which are known to output UV-C light incident upon the location of a particular remote monitoring device 200 may be controlled based upon the required output value calculated using the measured UV-C intensity provided by that specific remote monitoring device 200.

An algorithm is used to optimise the control of the output of the fluorescent tubes 101 a and to ensuring that sufficient UV-C light for disinfection is incident upon the location of each of the remote monitoring devices 200 where, for example, the same tube 101 a is known to output UV-C light incident upon the location of multiple remote monitoring devices 200.

Advantageously, the efficiency of the disinfection system is further enhanced as a result of the above outlined controlling of the luminaire assembly 100. Reduced time of whole room decontamination is also achieved and the efficacy of the disinfection process is guaranteed by the monitoring of UV-C concentration at actual target surfaces. The disinfection system may comprise multiple luminaire assemblies 100. Here the luminaire assemblies 100 may work in tandem to treat larger areas.

The disinfection system may be used to disinfect surfaces in healthcare environments, food production facilities and in public areas.

The disinfection system may be used to disinfect an enclosed space. An example of how the disinfection system may be used in a healthcare environment by an operator shall now be described. The operator may first carry out a manual cleaning of the room to be disinfected and its contents.

The operator may then position the contents of the room in the most appropriate way, exposing surfaces and taking precaution to avoid shadow areas

The operator may then position the luminaire assembly 100 within the enclosed space. Preferably, the operator would position the light source 101 at a central location in the room so that output of luminaire assembly 100 is as evenly distributed around the room as possible. However, the need for precise positioning of the luminaire assembly 100 (as is required when using existing UV-C disinfection systems) is obviated by the aforementioned use of the remote monitoring devices 200 and the control system 301.

The operator may then place the remote monitoring device or devices 200 evenly around the room and as far as possible from the luminaire assembly 100.

The operator may then take the remote user interface 303 and place it outside the room. The operator may then carry out a preliminary flash test of the room, optionally via the remote user interface 303. Here the device emits a short UV-C burst and the remote monitoring devices 200 each provide a measured UV-C intensity. The control system 301 uses measured UV-C intensity provided by each remote monitoring device 200 and a computational algorithm to determine the likely treatment time (i.e. by taking the light exposure at the remote monitoring devices 200 point and dividing it by the total light exposure required). Any potentially shadowed areas that might not be effectively decontaminated are also identified as the measured intensity would be below a threshold value in these areas.

If the flash test is unsuccessful, the operator repositions the luminaire assembly 100 to a more appropriate place and/or introduces a further luminaire assembly to the disinfection system.

If the flash test is successful, the operator is informed and requested to confirm that the room has been set up appropriately and the operator then initiates the decontamination process. The operator may be prevented from initiating the decontamination until a successful flash test has been performed.

The luminaire assembly 100 is subsequently switched on and begins to emit UV- C into the room.

Throughout the disinfection process, the disinfection system may monitor for any personnel in the space and will switch of the luminaire assembly 100 in the event of any person accessing the room. Throughout the process the control system 301 may communicate with each of the remote monitoring device 200 in the room and determine the sufficient UV-C exposure point. At the end of the process the remote user interface 303 located outside the room may inform the operator of the status of the process (i.e. successful, not successful). The disinfection system may log a cumulative UV-C exposure level for each remote monitoring device during each decontamination process for audit/evidence purposes.

The disinfection system may indicate when the UV-C emitting devices are due for replacement by detecting, for example, a diminished output power detected at a remote monitoring device 200 and subsequently notifying the operator.

The control system 301 may be in radio communication (or any other form of wireless communication) with the luminaire assembly 100. Should this link be lost, the luminaire assembly may automatically shut down the luminaire assembly 100 for safety.