Hand Unit

This invention relates to a unit for cleansing both small items and human hand(s). The invention is particularly adapted for cleansing such hand(s) and items used in hospital and in particular for virus sterilisation and deactivating viruses or other organisms containing RNA or DNA which may be present on such hand(s) or items.

It is known in hospital for visitors to attempt to sterilise their hand(s) using gels such as alcohol based gels or for visitors to regularly wash their hand(s). It is also known for Nurses to wear gloves, changing the gloves frequently and not using the same gloves between different patients. These methods of preventing cross contamination are only partially effective and require multiple and frequent actions. This is particularly true for nurses and doctors who will need to hand wash and glove change on a very frequent basis. Hand gel use also requires some technique/thoroughness to be truly effective and ifinot applied all over the hand(s) its usefulness is limited. This is problematic when it is carried out by untrained persons such as guests visiting patients. Such gels may also be less effective against viruses than they are against bacteria.

It is known to use ultraviolet light to deactivate viruses for example in water treatment whereby water is passed through a region of ultraviolet light in the cleaning process. This requires the complication of the water to be pumped through the region of UV and for the section to be sufficiently long to ensure deactivation of all viruses in the water. In order to cleanse solid objects, it is known to provide hand held units to shine ultraviolet light on items in order to cleanse them by deactivation of viruses. However, use of such hand held units requires the user to take considerable health and safety measures to prevent harm both to themselves and anybody else within the vicinity. Accordingly, typically protective clothing including gloves and goggles are worn by a user in order to reduce the risk of excess exposure to ultraviolet radiation. Moreover, it cannot be determined accurately how much of the surface of the item has been irradiated in such a handheld operation.

It is also known to use UV light on hands for other purpose such as curing nails but this is done with UV A light at a wavelength of around 380-400 nm which is not found to be effective for sterilisation.

An object in the invention is to provide a unit which allows for at least some biological sterilisation of hand(s) or gloved hand(s) whilst mitigating some of the above mentioned problems. Another object of the invention is to allow UV exposure to be used on the hand(s) without causing unnecessary exposure to the individual or those around them from the ultraviolet radiation.

According to the first aspect of the invention there is provided a hand disinfector comprising a body, the body defining a chamber for location of one or more hands to be disinfected and an opening through which one or more hands can be passed into the chamber, wherein the disinfector comprises a UV light source positioned to irradiate the chamber.

Preferably the UV source irradiates UV with a wavelength shorter than 350 nm, more preferably shorter than 300 nm and/or is around 250 or 254 nm.

Preferably the unit comprising a timer in communication with the UV source which turns off the source after a preset time, such as around 3 seconds, of use and which in operation prevents hand(s) from being continuously exposed to UV for more than the set time. Preferably the unit comprises a sensor in communication with the UV source arranged to detect when hand(s) have been placed in the chamber and which in use turns on the UV source and begins irradiation of the hands when the sensor detects hand(s) begin entered into the chamber. More preferably the timer is in communication with the sensor and configured to start its preset time duration when the sensor detects a hand and/or the sensor comprises a light detector located on a first side of the chamber and the chamber comprises a reflector located on a second side opposite the first side, wherein the sensor detects a hand when a sufficient amount of the light from the reflector is blocked from reaching the light detector. Preferably still the sensor

comprises a light source such as an LED arranged to radiate light onto the reflector for reflection onto the light detector.

Preferably the unit comprises a plurality of UV sources and more preferably comprises a first bank of UV sources disposed along a first surface of the chamber and a second bank of UV sources disposed along a second surface of the chamber which is preferably opposite the first surface. More preferably the banks comprise five or six UV sources and/or the banks of sources are disposed linearly along the length of the inserted hand in use.

Preferably one or more UV source comprises a tube, more preferably disposed so that in use is substantially perpendicular to the fingers of the inserted hand.

Preferably the disinfector comprises a reflector, which may be parabolic, curved away from the opening and/or have substantially constant curved cross section and/or . , positioned in proximity to the UV source and arranged to reflect radiation from the source into the chamber and/or onto a hand in use. More preferably the reflector is positioned between the opening and the UV source, preferably the disinfector comprises an absorber to absorb UV radiation from the UV source preferably located in proximity to the source, the corresponding source is positioned between the opening and the absorber, and/or is black. More preferably it has an element located between two UV sources, the element comprising a first surface which faces the opening and comprises the absorber and a second surface facing away from the opening which comprises the reflector. Preferably the unit comprises a reflector/absorber for each UV source in the first and/or second bank Preferably still there are two further sources without a corresponding reflector/absorber.

Preferably the disinfector comprises a barrier which permits UV radiation to be transmitted through it such as a wire gauze, the barrier located inside the chamber and defines the area into which the hand(s) are contained in use, and which prevents the hand from easily touching one or more of the UV source, reflector or absorber. Preferably the chamber/area inside the barrier is dimensioned to accommodate two

hands but does not have a significant amount of extra space and/or is one or more of more than about 15/20 cm deep, less than about 30 cam deep, more than about 50cm wide, less than about 70cm wide

Preferably the disinfector comprises a housing, which maybe separated from the chamber by a reflective surface, containing electronics such as a fuse block, a starter for each UV source and/or a ballast for each UV source.

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

Figure 1 is a schematic side sectional view of the embodiment of the invention,

Figure 2 is a schematic front view of the embodiment of Figure 1,

Figure 3 is a schematic wiring diagram of the circuit linking the components of the embodiment of Figures 1 and 2.

Referring to Figures 1 and 2, there is shown a hand disinfecting unit 10 according to the invention comprising a main body 12, defining an internal chamber 14 and a compartment 15.

The chamber 14 is completely sealed by the main body 12 on five of its sides but has an opening 16 at its front end. Surrounding opening 16 is an apron 18.

Apron 18 has two faces, a front vertical face 17 and a horizontal face 19 which extends backwards into the chamber 14. Front vertical face 17 extends from the edges of the front face of body 12, inwardly and delimits the size of opening 16. Horizontal face 19 is painted matt black to eliminate reflection of radiation from its surface helping to reduce the amount of radiation leaving through the opening 16.

Within the chamber 14 an area is delimited by a wire gauze 20 bent to form a substantially cuboid form in shape. The cuboid like form has five faces constructed of wire gauze with the face adjacent opening 16 having no wire and being completely open. The area delimited by the wire gauze 20 has a length just greater than that of a large human hand and a height great enough to accommodate most sizes of hand but is not unnecessarily larger than this. The width as seen in Figure 2 allows for two human hand(s) to be put side by side to fit comfortably within the chamber 14 and again is not unnecessarily larger than this. Consequently, the total width W as depicted in Figure 2 of unit 10 is 60 cm and the total depth D as depicted in Figure 1 is 24 cm. In an alternative embodiment the cuboid form of wire gauze 20 may have three open faces, including those adjacent the side walls of the chamber 14.

Referring to Figure 1 it can be seen that on each of the inside top and bottom surfaces 22 and 24 of the body 12 that there is a bank 26 and 28 of ultraviolet lamps 30. hi this embodiment the ultraviolet lamps 30 are a number of tubes which extend along the width of the unit 10 and are of a substantially similar length to the width of the chamber 14. Each of the banks 26 and 28 in this embodiment have five UV lamps 30.

The lower and upper surfaces 22 and 24 also comprise an array of reflectors 32. Each array comprises five reflectors 32 which are arranged along with banks 26 and 28 so that reflectors 32 and lamps 30 alternate in sequence.

Each reflector 32 has a curved profile resembling part of a shallow parabola. The profile has a relatively straight lower section 34 adjacent to the surface 22/24 and a top portion 36 which curves backwards away from the opening 16 partially across the top of the corresponding lamp 30. Each reflector 32 is painted matt black on the side facing the opening 16 to absorb any reflections of UV radiation which reach it. The side of the reflector 32 facing away from the opening 16 is metallic and shiny to optimise reflections into the area delimited by the wire gauze 20 and away from the opening 16.

As can be seen in Figures 1 and 2 the reflectors 32 intermingled with lower bank 26 are significantly taller than those corresponding to upper bank 28. It can also be seen from

the cross section in Figure 1 that the reflectors are very thin, being effectively just a piece of sheet metal, but that widthways as shown in Figure 2 they extent right across the full width of the chamber 14.

There are two further UV lamps 38 and 40 which are located on the lower surface 22 and upper surface 24 respectively and which are positioned behind the last lamp of the banks 26 and 28 and do not have a corresponding reflector 32.

At the end of chamber 14 opposite the opening 16 there is a panel 42 which separates the chamber 14 from compartment 15. On the side of panel 42 facing the chamber its surface is reflective in silver or white in order to reflect UV radiation from lamps 38 and 40 into the area delimited by the gauze 20.

Compartment 15 hides a ballast 44 and a starter 46 for each of the UV lamps 30 and also contains a fuse block 48.

Positioned on the inside side walls of the body 12 are a sensor and timer unit 50, which includes a light sensitive switch, and a flat reflector 52. The sensor and timer unit 50 and the flat reflector 52 face directly opposite each other. The flat reflector 52 is positioned to reflect visible light directly onto the sensor 50. Both the sensor unit 50 and flat reflector 52 are positioned at a level where the hand(s) should be inserted.

The sensor and timer unit may have a small light source such as an LED which transmits along the width of the unit 10 and hits a reflector 40 before returning back to the sensor unit 38. Alternatively it may rely on the reflection of ambient light.

Each of the UV lamps 30 operates with UV at about 254 nm which is found to be particularly effective at virus sterilisation and deactivating viruses or other organisms containing RNA or DNA

Referring to Figure 3 there is shown wiring for one lamp 30. This is repeated for each of the ten lamps 30 in the unit 10.

The circuit 56 links a power supply 54 to the sensor and timing unit 50 and through the fuse box 48 onto each of the lamps 30 and corresponding ballast 44. An example illustrating only one lamp 30 is shown, the amp 30 being connected in series with only one ballast 48 to complete the circuit. Each of the lamps 30 is then connected in series with its corresponding ballast 48, but is in parallel with each of the subsequent ballasts 48 and lamps 30. Also in parallel with lamp 22 is the starter 46 corresponding to the particular lamp 22. This starter is needed to commence the lamp and may also connect to timer unit 50.

In use the user inserts their hands into the opening 16 fully so that all of their hands are contained within the chamber 14. The design of the unit 10 preferably produces a clearly defined cut off line just short of where a cuff of a standard surgical glove would be. The hands are inserted and block light being reflected by reflector 52 onto the sensor 50. With the light blocked the sensor's light sensitive switch triggers and starts the timer in the timer unit 52 and or which instructs the starters 46 and/or ballasts 44 to turn on each of the lamps 30. Typically the timer unit 52 would then instruct the lamps to turn off after a period of about three seconds which has been found to be as suitable time for achieving sufficient sterilisation without too much UV radiation exposure.

Whilst the hands are inside the chamber 14 they are prevented from touching or going too close to the lamps 30 and reflectors 32 by the wire gauze 20. For this reason the gauze is preferably fine enough not to let even small fingers protrude through it.

In use the shiny side of reflectors 32 with their carefully chosen angles ensure that UV radiation distribution is optimised in covering the inserted hands in a controlled and spread manner. Additionally it ensures that none of the lamps from the lamps 30 goes directly in the direction of opening 16 without first hitting another surface, in order to reduce escape of radiation from unit 10. This is further aided by the matt black side of the reflectors 32 and by matt black surfaces 19 which help eliminate unwanted reflection. Panel 42 also reflects light back from the lamps 30 in particular 40 and 42 onto the hands. It is found that lamps 38 and 40 do not need a reflector with matt black

surfaces on one side as they are far enough away from the opening 16. Likewise whilst panel 42 does reflect some light in the direction of the opening 16, because of its distance from it and the amount of absorbing matt black surfaces between it and opening 16 the total light omitted from the opening 16 is very small.

The unit 10 can be used with gloved hands. Whether or not it is being used on gloved or naked hands may affect the length of time for which timing unit 50 is set and/or the power of the lamps 30. The UV intensity can be of any suitable level and can be increased or decreased by using different wattage lamps and by using resistance or other suitable controlled means. The lamps are preferably of a shatter proof material and preferably the disinfector is positioned so that a person's body is directly in front of the disinfector providing a further screen to any UV light spillage.

It is preferred that no door or screen is used across the opening 16 as this can itself be a target for contamination particularly if it obstructs easy entry of the hands.