WO2013171472A1

WO2013171472A1 - A device for use in swabbing a surface

Info

Publication number: WO2013171472A1
Application number: PCT/GB2013/051235
Authority: WO
Inventors: Walter Anderson
Original assignee: Walter Anderson
Priority date: 2012-05-14
Filing date: 2013-05-14
Publication date: 2013-11-21
Also published as: GB201208357D0

Abstract

The invention relates to a hand-held torch which for use, primarily, in assessing the hygiene within a food-processing environment. The device has a light source which is used to project an image onto a work surface which defines an area to be swabbed. The torch includes two or more projectors each projecting a beam onto the surface to aid in ensuring that the torch is held at the correct height and orientation above the surface. The analyst can then swab the defined area using a sterile swab. A device is also disclosed, mountable to a user's arm or wrist to hold swabs in a vertical orientation. Containers for swabs are mounted on a gimbal or ball joint to e sleeve worn by the user, which containers may be weighted at their in-use lower end to ensure that the containers remain upright.

Description

A Device for use in Swabbing a Surface

Field of the invention The present invention relates to a device for use when determining the presence or otherwise of microbial organisms on a surface, especially through taking samples with a swab. Also disclosed is a method of taking such a sample. The device and method are also suitable for use when sampling for other organic entities such as ATP or proteins, Background of the Invention

Within the food handling and processing industries., great care must obviously be taken that microbial, pathogens are not present, at a level which can cause illnesses in the consumer. Although many steps undertaken during food processing kill off pathogens or toxins produced by the pathogens_., there is nevertheless still a risk that contamination can be introduced at other stages, such as packaging or transportation within the production factory. Care therefore needs to be taken that transient micro-organisms do not become resident and thereby a greater threat. A handling regime is essential in order to minimise risks. Although no statutory measures are in place which lay out precisely how the monitoring of pathogens is to take place, IS0185932004 {£} does provide a basis, indicating the critical steps which should be included: especially with respect to certain aspects of sampling. Monitoring programmes need to be set up as part of the overall hygiene schedule, The schedule should have as its prime asm the maintenance of pathogen levels at a safe value. Monitoring of an area is typically carried out on a regular basis according to a schedule drawn up by those responsible for the Health & Safety of the process. The frequency and level of monitoring is set according to the risk factors associated with that area and can be such that tests are run after each batch is produced or only every six months. To assist in achieving this aim, diagnostic tools are available which can indicate both when a pathogen is under control but can also provide a guide as to a route by which pathogens are entering into a food processing system, enabling that route to be blocked. As with overall monitoring, no statutory regulations are in place for the methodology to he used in carrying out sampling and analysis of an area, or even what microbe or chemical is to be measured. Many analysis regimes test for specific microbes such as conforms, salmonella spp or listeria spp. Others analyse for adenosine triphosphate (ATP), although there is disagreement as to the efficacy of this analysis as ATP can result from both living and dead organisms and is moreover not present in all organisms, Yet further methods simply analyse for proteins,

One method of sampling a surface which is widely used involves rubbing a swab across the surface under examination and then passing the swab for analysis. Swabs and the analytical methods can vary, but usually only within certain parameters so that a good indication of the presence and level of the subject of the test is provided.

In order to standardise test methods, the swab is rubbed over a defined area, often 100 cm². The shape of the area tested is selected to suit the particular case in hand. To assist the analyst, templates defining a sampling area are available and which are laid on the surface. The templates will, however, normally have to be disposed of afterwards to avoid any future cross-contamination. In addition their use also increases the risk of the analyst accidentally touching the surface, which can again provide a false reading at some point in a sampling scheme.

It would be advantageous therefore if a sample were able to be taken in a manner which minimised contact with the surface being analysed. It is an object of the present invention to provide a device which addresses this problem. It is a further object of the invention to provide a method of sampling which also addresses this problem. According to a first aspect of the invention there is provided a hand-held torch device for use when determining the cleanness of a surface, the device comprising: a light source and power for said light source, the light source being capable of illuminating a surface and projecting an image of a polygon onto a surface, such that when the device is at a pre-determined height and orientation above a surface the image of the polygon has a pre~determined area; the device further comprising two or more light projectors each so directed to project a light beam non-parallel to the or each other beam, and such that when the device is the correct height and orientation above a surface the beams meet at a point on a surface.

Preferably, said surface point is indicated on a surface as that projected by a predetermined point intermediate the light source and a surface. The device therefore provides a simple method of highlighting an area of pre-defined value without the user having to touch the surface except to take a sample.

Further preferably the surface point is a point projected on the image of the polygon, Alternatively, the surface point is a point projected by a third projector located within the device, The above ensure that the polygon is of the correct area by ensuring the correct orientation and height of the device.

Conveniently, the device includes a transparent screen interposed between the light source and a surface. The screen can act to protect the light source.

Preferably the device includes a polygonal shape interposed between the light source and a surface to provide an image of a polygon on a surface. Optionally, the polygonal shape is incorporated into the screen. Yet further optionally, the polygonal shape and/or the screen are replaceable to enable the device to be used to project different shapes onto a surface.

Conveniently the polygon is divided into a grid to assist in the swabbing procedure. The device preferably projects an image having on the surface, a size of 1 , 10, 25 or 100 cm².

According to a second aspect of the invention there is provided a method of taking a swab, the method including the steps of selecting a device in accordance with the first aspect of the invention, illuminating the light source and aligning the projected beams correctly such that the beams meet at a point on a surface, selecting a swab and swabbing the area inside the image of the polygon. A further aspect of the invention comprises a quiver to contain one or more swabs whilst the above device and method are being employed. The quiver is mourvtable about an arm or a wrist of a user and comprises compartments each able to house a single swab, the compartments preferably being mounted on a girnbal to retain the swabs in a vertical orientation. Further preferably the compartments are weighted at their in use lower end to ensure that the compartments remain in the vertical orientation,

8ri¾f Description of the Drawings

The invention is now described with respect to the accompanying drawings which show by way of example only two embodiments of a torch device and of a quiver. In the drawings:

Figure 1 is a perspective view of a first embodiment of a torch device;

Figure 2 demonstrates the use of the torch of Figure 1 in conjunction with a quiver; and

Figure 3 is a section through a second embodiment of a torch device.

The present invention is intended to assist an analyst when taking samples from a surface, which samples are to enable the presence and extent of microbes, ATP or other organic material to be determined. The device enables the analyst to define an area which is to be analysed without having to disturb or come into contact with the area. Moreover, the area or region defined is of a pre-deterrnined size to enable a comparison with previous results or standards to be made.

Typical prior art methods of defining a region utilise a frame, the internal edges of which enclose a set internal area of the required dimensions, The frame is laid on the surface under examination leaving the surface defined by the frame accessible; the sample is then taken, usually by means of a swab, from the internal area. This method has the obvious disadvantage that contact with the surface being investigated needs to be made, at least by the frame which, even if the frame is carefully placed, gives rise to the possibility of cross-contamination or a false reading.

The present invention enables a region of defined size to be shown on the surface without the user having to touch the surface, in order to achieve this, a light is shone onto the surface, such that when the light source is correctly positioned, the area defined by the light on the surface is that which is required for the sample. Means are also provided, associated with the light source, which ensure that the positioning is correct.

The principal features of the device are illustrated in Figure 1. in this figure, the device 10 has a handle 11 for the user to grip whilst in use. The handle 11 may also house the energy storage elements such as one or more batteries to provide energy for the light source {not illustrated). Additionally, the handle 11 can be profiled to ensure that the user's fingers can properly hold the device in a steady position for the time required for a sample to be taken from the surface, Across the end of the device 10 is a transparent cover 12 made of glass, Perspex^RiM or other plastics material. Light emitted by the light source therefore is able to pass out of the device 10, The cover 12 illustrated, has incorporated therein, for example by a frame or by etching on the cover, an outline of a square or rectangular shape 13 the shadow of which in use becomes projected onto the surface. It will be appreciated that other polygons, which should be taken to include circles, ellipses and the like, including irregular shapes, can also be used. This feature can optionally be omitted, in which case the edges of the flared end 14 of the device will form the edge of the image projected onto the surface. However, the image might then be less well defined. The cover 12 can be replaceable so that the device 10 is able to project onto the surface, other polygonal Images and also images having different areas should the sampling method so require. In an alternative embodiment not illustrated, the outline of the polygonal shape can also be incorporated into the device separately from the plate 12 and, further, can be replaceable to increase the flexibility of usage of the device.

It will also be recognised that alternative shapes 13 can be used without departing from the scope of the invention. Again in the embodiment shown, optional markings 15 are included along one or more edges of the shape 13. In a further embodiment, not illustrated, the shape 13 may include an infernal grid to aid in sample taking.

In order to be able to ensure that the device 10 is positioned at the correct distance and orientation with respect to the surface, the device 10 includes two directed light projectors 16a, 16b. The projectors 16a, 16b can receive light from the same source as from the main beam emitted by the primary light source of the device or can include their own separate light sources. The light emitted by the projectors can be directed through the use of glass-fibre bundles or can simply be LEDs, or the like, set into or beneath the plate 12. Alternatively, the projectors can be secured to the outside of the flared region 14. In a preferred embodiment, the light source for the projectors each comprises a laser. The projectors 16a, 16b are so mounted that the light beams emitted are angled towards each other, Moreover, when the distance of the device 10 from the surface is correct the emitted beams are set to meet at the surface, in an optional embodiment, and to ensure that the device 10 is both at the correct distance from the surface and also at. the correct orientation to ensure that the area defined by the light is correct, then the beams are also set such that when they meet on the surface they coincide with a particular part of the illuminated area, such as a corner of the projected shape 13. Alternatively, a third projector can be included and the correct distance and orientation is then achieved when the three projected beams meet at a point, In Figure 3, a further embodiment of a device 30 is illustrated. The LED light source 31 is located within a well 32. Two projectors 33a, 33b, each comprise a laser emitter which emits a beam of red light although other colours, or even infra-red or ultraviolet can be used if appropriate. The beams emitted by the projectors 33a. 33b are not parallel to each other and meet at a point on the surface being investigated, when the device 30 is at the correct height above the surface. A. screen 34 is generally opaque, but has a rectangular aperture and two apertures, The latter apertures allow the beams emitted by the projectors 33a, 33b to pass through. The rectangular aperture allows light from the source 31 to pass through and causes, in use, a rectangular image to be projected onto a surface, It will be recognised that an aperture, as indicated above, can refer to a hole either partially or completely through the screen 34 or to a region where the opacity is reduced₍ or the screen is clear.

It has been found advantageous to set the light source 31 sufficiently deeply within the well 32 that the image projected on the surface is well-defined. If the source 31 is too close to the aperture this gives a diffuse image on the surface, in a further embodiment not illustrated, a lens is included in the screen 34 to sharpen the image further.

Using the above devices, an area of, for example 1, 10, 25, 100 cm² can be defined on a surface, in use therefore, a typical analysis would take place as follows, Firstly, an area to be tested is identified. A user washes and sanitises their hands before opening a sterile swab, if necessary the swab is wetted using a sterile diluent. A device 10 is taken and the light source(s) illuminated, The position of the device 10 is adjusted such that the beams from the projectors 18a, 16b meet on the surface, and optionally at a predetermined point of the main image of the shape 13 on the surface. A sterile swab is wiped across the surface to be swabbed, within the area defined by the shape's image ensuring that that entire surface is contacted by the swab,

Once sampling using this swab is complete, the swab is placed back into sterile diluent If required, the sample and the swab are refrigerated prior to analysis taking place.

The device 10 as described above can be used in conjunction with a holder for the swab, the holder being designed to be worn by the user. The holder 20, as illustrated in Figure 2, comprises a cuff 21 worn about the user's forearm or wrist. A plurality of holders 22 for swabs is mounted by means of a ball joint or gimbal 23 to the cuff 21. This arrangement allows the holders 22 to remain in a substantially vertical orientation during use. in addition, weights 24 at the bottom of the holders 22 facilitate the maintenance of this orientation. As illustrated therefore, the swabs are easily storabie after use, with the one hand being left free to hold the device 10 and the other to use the swabs.

Using the device 10 as described above therefore an accurate sample can be taken from the surface, which sample can then be analysed for organisms, ATP, proteins or the like.

The light source as used herein may be produced by an incandescent bulb, LED, LCD or OLED light. In addition the light source used can be a laser light source. Furthermore, electromagnetic radiation from other parts of the spectrum can be used; for example infrared or ultraviolet. The use of such radiation can be used to assist in determining whether or not a particular surface has been treated, Alternatively, the radiation can be used to locate the sample area in order to enable a robot arm to carry out the analysis. Moreover, alternative means to electromagnetic radiation, such as sound-waves, ultrasound or magnetic field proximity measures can be used to ensure the correct distance and orientation of the device is achieved. Where necessary, a receiver can be included in the device to pick up the reflected signal.

The device 10 as described above is also suitable to be incorporated into a smart phone, PDA or other hand-held data acquisition device. Alternatively, to assist a user in keeping their hands free during sampling, the device can be mounted to the user's body, such as to the head or torso.

Claims

1. A hand-held torch device for use when determining the cleanness of a surface, the device comprising: a light source and power for said light source, the light source being capable of illuminating a surface and projecting an image of a polygon onto a surface, such that when the device is at a pre -determined height and orientation above a surface the image of the polygon has a pre-derermined area; the device further comprising two or more light projectors each so directed to project a light beam non-parallel to the or each other beam, and such that when the device is the correct height and orientation above a surface the beams meet at a point on a surface,

2. A device according to Claim 1 , wherein the surface point indicated on a surface is that projected by a predetermined point intermediate the light source and a surface,

3. A device according to Claim 2, wherein the surface point is a point projected on the image of the polygon.

4. A device according to Claim 1 , wherein the surface point is a point projected by a third projector located within the device.

5. A device according to any preceding claim, including a transparent screen interposed between the light source and a surface.

6. A device according to any preceding claim, wherein the device includes a polygonal shape interposed between the light source and a surface.

?. A device according to any of Claims 1 - 5 wherein a polygonal shape is incorporated into the screen.

8. A device according to Claim 6 or Claim 7 wherein the polygonal shape and/or the screen are replaceable.

9. A device according to any preceding claim, wherein the polygon is divided into a grid.

10. A device according to any preceding claim, which projects an image having on the surface a size of 1, 10, 25 or 100 cm².

1 1. A method of taking a swab, the method including the steps of selecting a device in accordance with one or more of the preceding claims, illuminating the light source and aligning the projected beams correctly such that the beams meet at a point on a surface, selecting a swab and swabbing the area inside the image of the polygon.

12. A device substantially as herein described with reference and as illustrated by Figure 1 ,