GB2501102A

GB2501102A - Drawer assembly for holding medical items during bio-decontamination

Info

Publication number: GB2501102A
Application number: GB1206469.7A
Authority: GB
Inventors: Christopher Andrew Ferry
Original assignee: Bioquell UK Ltd
Current assignee: Bioquell UK Ltd
Priority date: 2012-04-12
Filing date: 2012-04-12
Publication date: 2013-10-16
Also published as: GB201206469D0; WO2013153377A1

Abstract

A drawer assembly which can be assembled in different ways to provide different drawer units suitable for holding medical items during bio-decontamination. The invention provides a kit of parts comprising: a plurality of drawers 10 having drawer interlocking means 25 for securing one drawer 10 to another drawer 10; and a frame (70) comprising a plurality of pairs of rails (76) for slidably receiving and supporting drawers 10. The kit of parts is assembleable to provide at least two different configurations of drawer unit. In a first configuration at least one drawer 10 is located directly on top of another drawer 10 and is secured to the underlying drawer 10 by configuration the drawer interlocking means 25. In a second configuration, drawers 10 are each supported by a pair of rails (76) in the frame (70).

Description

DRAWER ASSEMBLY FOR HOLDING MEDICAL ITEMS DURING BlO

DECONTAMINAT ION

This invention is directed towards a drawer assembly, which can be assembled in different ways to provide different drawer units suitable for holding medical items during bio-decontamination, wherein the drawers of the assembly may be either vertically stacked one on top of one another or slidably mounted on rails inside a frame.

In medical environments, such as hospitals and laboratories, pharmaceutical or medicinal products or prescriptions often need to be prepared under sterile conditions, similarly medical instruments, such as syringes and surgical instruments, need to be sterilised prior to use. Isolation chambers are commonly used to create the necessary sterile conditions as they provide a physical separation of the process from the surrounding environment.

Such isolation chambers may be decontaminated manually, for example by using an alcohol-based spray and hand wipe, or by utilising a decontamination system integrated within the isolation chamber. The latter may utilise a decontaminating gas which is injected into the isolation chamber, thereby sterilising the contents and inside walls of the isolation chamber.

Examples of isolation chambers include the SKAN Pharmaceutical Safety Isolator with an integrated SIS-A hydrogen peroxide bio-decontamination system and the Getinge ISOCYT FREJA containing the STERITRACE II hydrogen peroxide bio-decontamination system. Examples of pharmacy workstations are described in US-B-6588548 and US-E-5511594.

During decontamination, it is common to use vertically stackable trays to hold the items. An operator will position the trays and prepare prescriptions from the items inside an isolation chamber utilising gloves attached to the inside of a wall of the isolation chamber. Such gloves reduce the dexterity of the operator so it is important that it is easy to access the items in the trays.

To optimise throughput times it is desirable to decontaminate more than one batch of items at a time, for example the items reguired for preparing multiple prescription orders. However, when the trays contain medicinal products and items for the preparation of a prescription, it is vital to ensure that the products required for one prescription are not mixed-up with products for another prescription or contaminate them. In partioular it is important to ensure that, if the trays are knocked over, the products do not fall out easily as in the open baskets used in the Getinge system.

A tray system comprising stackable trays for holding surgical instruments is disclosed in US-A-2004-0144670. Each tray is secured to the tray above by a latch located at each end of the tray. A lid is used to cover the top tray. The trays and lid comprise holes to allow for the circulation of sterilising steam. Although such stackable trays are a compact means of holding medical items and are held together securely, they have the disadvantage that the products in all except the uppermost tray are difficult to access. Such difficulty is exacerbated when trying to access the products using isolation chamber gloves.

US-B-5893618 discloses a stacking sterilisation tray assembly wherein the trays are slidably mounted in a rack.

The trays comprise a plurality of spaced apertures to allow gaseous sterilants to enter and exit the trays. Removable end caps are secured to the end of the rack to prevent the trays from falling out. However, due to the design of the trays, the surface area of the items in contact with the trays is not minimised to ensure occlusion of the pharmaceutical products within the tray. Furthermore if only a small number of items are required for sterilisation, the whole unit must still be used.

The present invention is directed towards improving upon the stackable tray apparatus highlighted above.

The invention provides a drawer assembly comprising; a plurality of drawers having drawer interlocking means for securing one drawer to another drawer; and a frame comprising a plurality of pairs of rails for slidably receiving and supporting drawers; wherein the drawer assembly is assembleable to provide at least two different configurations of drawer unit; wherein in a first configuration of drawer unit at least one drawer is located directly on top of another drawer and is secured to the underlying drawer by the drawer interlocking means; and in a second configuration of drawer unit at least one of the drawers is supported on the rails in the frame.

By way of example only, embodiments of a drawer assembly suitable for holding items during bio-decontamination is now described with reference to, and as shown in, the accompanying drawings.

Figure 1 is a perspective view of a drawer of the drawer assembly of the present invention; Figure 2 is a perspective view of the underside of the drawer of Figure 1; Figure 3 is a perspective view of a lid of the drawer assembly of the present invention; Figure 4 is a perspective view of the underside of the lid of Figure 3; Figure 5 is a perspective view of a stack of the drawers of Figure 1 closed by the lid of Figure 3 to provide one embodiment of the drawer assembly of the present invention; Figure 6 is a perspective view of the rear of the stack of drawers of Figure 5; Figure 7 is a perspective view of a frame of the drawer assembly of the present invention; and Figures 8 and 9 are perspective views of the frame of Figure 7 containing the drawers of Figure 1 to provide another embodiment of the drawer assembly of the present invention.

The present invention is generally directed towards a drawer assembly which can be assembled in different ways to form at least two different configurations of drawer unit suitable for holding medical items and the like during bio-decontamination. The drawer assembly comprises a plurality of drawers, which may be stacked on top of one another and features of the drawers secure each drawer to another drawer to form a first form of drawer unit. The drawer assembly further comprises a frame into which the drawers may be inserted to form a second form of drawer unit. The drawer assembly further comprises a lid, which may be secured to the top drawer of the stack or the top drawer in the frame.

The lid is designed to support one or more syringes, one or more saline (or other pharmaceutical) bags and/or an identification card.

The drawers are suitable to hold a wide variety of different types of medical items, such as syringes, vials, ampoules, saline bags, medioaments and filters.

Alternatively, the drawers may hold other types of items for bio-decontamination such as, for example, items used in the defence industry. During bio-deoontamination, each drawer unit holds the items reguired to prepare a single patient's prescription. The identification card is used to identify the patient for whom the prescription is intended and may also comprise a visual indicator which indicates that decontamination has occurred. In order to prevent the mix-up of prescriptions, the drawer units are assembled In a manner which prevents the contents of the drawers from falling out when the unit is knocked.

Figure 1 illustrates a drawer 10 of the drawer assembly. The drawer 10 preferably comprises four side walls 11, 12, 13, 14 projecting perpendicularly upwardly from a base 15. Preferably, the drawer 10 is formed by injection moulding an ABS (Acrylonitrile Butadiene Styrene) or Polycarbonate and ABS mix. Alternatively, the drawer 10 may be formed by another plastic moulding technique or from separate components joined together. Each of the components may be formed from any material suitable for use In the bio-deoontamination process, such as aluminium, steel or polypropylene. In one embodiment the drawer 15 may be a certain colour which represents a particular type of medical items that will be placed in it or relating to the urgency of the compounded prescription.

The side walls 11, 12, 13, 14 are formed from a mesh 32 which comprises a plurality of horizontal pieces 30 and a plurality of vertical pieces 31. Caps 33 are formed in between the horizontal and vertical pieces 30, 31 to allow decontaminating gas to flow through the drawer 10 to reach the items located therein.

At least a part of a front side wall 13 may be comprised of a curved recess 34. At least one (and preferably two) handle 35 is attached to the front side wall 13. In one embodiment the handles 35 are hollow "D" shapes to provide convenient means for pulling the drawers 10 out of the frame 70. Conveniently the handles may be 20mm wide.

The base 15 is also formed from a mesh 17, which comprises a plurality of parallel transverse pieces 18 which intersect perpendicularly with a plurality of parallel longitudinal pieces 19. A plurality of gaps 20 are thereby formed in the mesh 17 to allow decontaminating gas to flow through the drawer 10 through the base 15.

In one embodiment the transverse pieces 18 intersect the longitudinal pieces 19 at an angle other than perpendicular to one another. The plurality of transverse pieces 18 may not be parallel to one another and/or the plurality of longitudinal pieces 19 may not be parallel to one another. In such an orientation, one or more transverse pieces 19 may also intersect with one or more other transverse pieces 19 and/or one or more longitudinal pieces 19 may also intersect with one or more other longitudinal pieces 19.

Preferably the orientation of the transverse pieces 18 relative to the longitudinal pieces 19, the distance between each of the plurality of transverse pieces 18 and the distance between each of the plurality of longitudinal pieces 19 are designed to prevent the medical items from falling through the gaps 20. Furthermore, the orientation and the distances are preferably designed such that the gaps are optimally shaped and sized to allow sufficient deoontaminating gas to enter the inside of the drawer 10 and be distributed around the medical items in an optimal manner for bio-decontamination.

In the embodiment illustrated in Figure 1, the orientation of the transverse pieces 18 relative to the longitudinal pieces 19 is such that the gaps 20 are sguare.

In an exemplary embodiment, the distance between each of the plurality of transverse pieces 18 and the distance between each of the plurality of longitudinal pieces 19 are such that the length each of the sides of the square gaps 20 is 10mm. In further embodiments the gaps 20 are any other shape, such as rectangular or triangular.

The shape of the cross section of the transverse pieces 18 and longitudinal pieces 19 is selected to reduce the area of contact between the base 15 and any items placed in the drawer 10 to thereby increase the surface area of the items exposed to the decontaminating gas. In the embodiment illustrated by Figure 1 the cross-sectional shape of the pieces 18, 19 is trianglular, wherein the top corner of the triangle is in contact with the medical items and the bottom side of the triangle is on the underside of the mesh 17. The triangular cross-sectional shape reduces the contact area between the mesh 17 and medical items as only the tip of the top corner is in contact with the medical items. Ihe cross-sectional shape may be any shape which results in a small contact area with the medical items, for example a circle, a quadrilateral, a pentagon or a hexagon.

An array of projections 21 may also project upwardly from the base 15. The projections 21 raise any items placed in the drawer 10 above the base 15 and thereby further reduce the contact area between the items and the base 15.

The projections 21 may comprise spikes, or sharp points, to minimise the contact area between the projections 21 and the items. Each projection 21 may be located at an intersection of a transverse and longitudinal piece 18, 19. As illustrated in the embodiment in Figure 1, the array of projections 21 may be arranged in a square grid, with each projection 21 located two intersections of transverse and longitudinal pieces 18, 19 away from any other projection 21. In alternative embodiments, there may be any number of projections 21 located at any point on the bottom mesh 17.

As illustrated in Figure 2, perpendicularly intersecting support pieces 22 may be provided on the underside of the base 15. The support pieces 22 add stiffness and strength to the base 15, which allows the cross sections of the transverse and longitudinal pieces 18, 19 to be shaped as mentioned above to reduce contact area with the items rather than providing the necessary strength to support the medical items in the drawer 10. Each support piece 22 is adjacent to and parallel with the underside of one of the transverse and longitudinal pieces 18, 19. There may be fewer support pieces 22 than transverse and longitudinal pieces 18, 19 and the shape of the cross section of the support pieces 22 may be square.

Drawer stops 23, preferabiy comprising raised protrusions, may be provided at the front of the underside of the base 15. Runners 24 may be provided along the length of the underside of the base 15 from the front to the rear of the drawer 10. The runners 24 are inset from the edge of the base 15. The runners 24 may be integrally formed with the support pieces 22. Catch means 26 are provided at the front edges of each drawer 10 and may comprise indentations provided at each of the front corners of the underside of the base 15.

A plurality of drawer interlocking means 25 are provided along the rear edge of the base 15 of each drawer 10. In the embodiment illustrated in the Figures, the drawer interlocking means 25 comprise cantilever hooks 25 located along the rear edge of the bottom side 15. The cantilever hooks 25 may be "L" shaped, wherein the gap and point of the hook 25 are at the rear of the base 15. The end of the point of the hook 25 may be flush with the rear edge of the base 15.

Figures 3 and 4 illustrate one embodiment of a lid 40 comprising a planar section 41 and a flange section 42 projecting perpendicularly downwards from a front edge of the planar section 41. The lid 40 is preferably formed by injection moulding a mixture of ABS and Polycarbonate, but may be formed of any other material utilising any other technigue. The lid 40 is securable to the top of a drawer 10 to prevent any items in the drawer 10 falling out if the drawer unit is knocked.

-10 -An identification card holder 43 may be provided on the flange section 42 of the lid 40, into which an identification card 44 may be inserted. The identification card holder 43 may comprise a plurality of slotted projections 45, 46, 47 and the edges of the identification card 44 are inserted into each of the slots. In one embodiment three slotted projections 45, 46, 47 are provided such that the bottom and side edges of the identification card 44 are inserted in the slots. io

The identification card 44 provides, using written, printed or electronic means, a variety of information about the contents of the drawer 10 on which the lid 40 has been placed. Such information might include the names, expiry dates and identification numbers of the items in the drawer and the name, patient number and date of birth of the patient for whose prescription whom the items are to be used for.

The identification card 44 may further comprise a visual indicator which indicates whether or not the identification card 44 has been in contact with a decontaminant and therefore whether or not the contents of the drawer 10 have been decontaminated. The visual indicator may comprise a chemical compcsition which changes colour upon contact with a decontaminating gas, and the rate of change of colour may be related to the length of time the visual indicator has been exposed to decontaminating gas. In a preferable embodiment, the decontaminating gas is hydrogen peroxide vapour and the visual indicator is a hydrogen peroxide indicator. One suitable hydrogen peroxide indicator is disclosed in the document US-A-2004/0265l70.

-11 -A substantial part of the planar section 41 of the lid is formed from a mesh 48 which, in a similar manner to the meshes 32, 17, allows decontaminating gas to flow through the drawer 10 even though onto which the lid 40 has been scoured to the drawer unit. The mesh 48 comprises a plurality of transverse pieces 49 intersecting perpendicularly with a plurality of longitudinal pieces 50.

Support pieoes 51 may be provided on the underside of the mesh 48 to provide strength and stiffness to the mesh 48.

Each support piece 51 may be parallel with and adjacent to a transverse piece 49 or a longitudinal piece 50.

A plurality of lid securing means 52 are provided along a rear edge of the lid 40. These may comprise cantilever hooks formed adjacent to the rear edge of the lid 40. The cantilever hooks may be "L" shaped, wherein the gap and point of each hook are at the rear of the lid 40. The end of the point of the hook may be flush with the rear edge of the lid 40. TNhen the lid 40 is placed over the top of a drawer 10, the hooks engage around, or interlock with, the uppermost horizontal piece 30 of the mesh 32 of the rear side wall 14 (see Figure 6) . The hooks thereby secure the rear edge of the lid 40 to the top of the rear side wall 14 of the drawer 10.

Side bars 53, 54 may be provided along the length of each side of the lid 40 on the underside thereof (see Figure 4) . The side bars 53, 54 are inset from the edges of the lid by a distance substantially similar to the width of the horizontal pieces 30 at the top of the side walls 11, 12 of the drawer 10. One or more protrusions 55 may be provided on the underside of the planar section 41, which locate inside -12 -or mate with an element of the handles 35 when the lid 40 is placed on the drawer 10.

One or more syringe holding means 56 and/or one or more medical (e.g. saline) hag holding means 57 may he provided on the lid 40. The holding means 56, 57 may support items which are too big for the drawers 10, so that they hang external to the drawers 10. In the embodiment illustrated in Figures 3 and 4 the lid 40 comprises syringe holding means 56 and medical bag holding means 57 located in between the mesh 48 and identifioation card holder 43. When the lid 40 is secured to a drawer 10 and the syringe(s) and/or medical bag are located in/on the holding means 56, 57, the syringe(s) and/or medical bag hang in between the front of the drawer 10 and the flange front section 42 of the lid 40.

The syringe holding means 56 preferably comprises means to hold the free, or proximal, end of the plunger of a syringe. The proximal end of a syringe plunger typically comprises a circular disc with a diameter larger than the diameter of the main plunger body. The surface area on the underside of the circular disc thereby forms an annulus around the end of the main plunger body. The circular disc enables the operator to use his/her thumb to depress the plunger into the syringe barrel.

The syringe holding means 56 may comprise a horizontal shelf upon the top of which the at least part of the annulus rests when the syringe is being held. The horizontal shelf may provide support around at least half of the circumferenoe of the circular disk. The horizontal shelf may be attached to the front section and/or the top section of the lid 40. When the syringe is in the syringe holding means -13 - 56 when the lid 40 is attached to a drawer 10, the syringe hangs in between the drawer 10 and the front section 42.

The medical bag holding means 57 may be adapted for holding any type of medical bag, such as a saline bag, and may be formed of a cantilever protruding from the rear side of the front section 42. The cantilever may be & I-beam, wherein the underside of the flange is supported by a plurality of webs. The cantilever is inserted through a hole at the top of the medical bag and the medical bag hangs by the edge of the hole resting on the top of cantilever. An upwards directed protrusion, or lip, may be provided on the top of the flange adjacent to the free end of the cantilever to prevent the edge of the hole in the medical bag from sliding off the cantilever.

Sheet holders 58 may also be provided on the lid 40 for securing a sheet of paper (e.g. medical information) to the drawer unit. The sheet holders 58 may comprise two hooks located adjacent to the corners on the rear edge of the top section 41.

Figures 5 and 6 illustrate a first form of a drawer unit wherein a plurality of drawers 10 and a lid 40 are stacked on and secured directly to one another utilising the drawer interlocking means 25. Other than the bottom drawer 10, each drawer 10 rests on the top of a lower drawer 10, leaving the full volume of the space defined by the side walls 11, 12, 13, 14 and base 15 for receiving the items.

Each drawer 10 in this drawer unit is secured to the underlying drawer 10 by the drawer interlocking means 25 which engage the top horizontal piece 30 of the rear side wall 14 of the underlying drawer 10. when the drawer unit is -14 -assembled, the drawer stops 23 are boated adjacent to the inside of the top horizontal piece 30 of the front side wall 13 of the underlying drawer 10 and prevent the overlying drawer 10 from sliding forwards relative thereto. The runners 24 looate inside the top horizontal pieces 30 of the side walls 11, 12 of the underlying drawer 10 and prevent the overlying drawer 10 from sliding sideways relative thereto.

The lid securing means 52 secure the lid 40 to the uppermost drawer 10, to which the lid 40 is attached. The lid securing means 52 engage the top horizontal piece 30 of the rear side wall 14 of the drawer 10. The side bars 53, 54 locate inside the top horizontal pieces 30 of the side walls 11, 12 of the underlying drawer 10 and prevent the lid 40 from sliding sideways relative thereto. The protrusions 55 locate inside or engage with the handles 35 to further secure the lid 40 to the drawer 10, thereby preventing the front of the lid 40 from sliding in any direction in the horizontal plane. The protrusions 55 may form a close or snap fit with the handles 35 to further secure the lid 40 in place.

Figure 7 illustrates a frame 70 of the drawer assembly for supporting a plurality of drawers 10 to enable the second form of the drawer unit to be assembled. The frame 70 comprises a top 71, a base 72, opposing sides 73, 74 and a rear 75. The front of the frame 70 is open to allow the insertion of drawers 10. The frame 70 may be formed from any material, for example, stainless steel, aluminium or a plastic. Each of the top, base, sides and rear 71, 72, 73, 74 and 75 are substantially cpen, such that when the drawers -15 -are supported in the frame 70 the deoontaminating gas may flow freely through the frame 70 and through the drawers 10.

A plurality of pairs of rails 76 are provided on the sides 73, 74. Each of the rails 76 runs horizontally along the inside of the sides 73, 74. The rails 76 are provided at vertical intervals of a similar magnitude to the height of each of the drawers 10. When a drawer 10 is inserted into the frame 70, the edges of the base 15 of the drawer 10 locate on and are supported by the pair of rails 76 on the opposing sides 73, 74. The rails 76 enable the drawer 10 to be slidably inserted into and removed from the frame 70.

A plurality of frame stops 77 may be provided on the frame 70 to interact with the catch means 26. In the embodiment shown, each of the frame stops 77 comprises a protrusion located at the front of each of the rails 76.

Each protrusion is suitably sized to engage with the catch means 26 of each drawer 10 and may comprise a rearward facing flat face against to contact a forward facing flat face of the catch means 26. rjchen the drawer 10 is supported by the rail 76, the catch means 26 and stop 26, 77 ensure that the drawer 10 does not slide out of the frame 70. To slidably remove the drawer 10 from the frame 70, the drawer 10 needs to be first manually lifted over the frame stops 77.

The base 72 of the frame 70 may comprise a plurality of runners 78 to enable the frame 70 to slide easily along a surface, thereby reducing the likelihood of it falling over during handling. In one embodiment, where the frame 70 is for use primarily on metal surfaces, the runners are made -16 -from ABS as the metal/ABS coefficient of friction is comparatively low.

The rails 76 and runners 78 may be formed from a first part comprising a compressible protrusion and a second part comprising a recess. The protrusion of the first part is inserted through a hole in the frame 70 and snap-fitted into the recess of the second part. The first and second parts may be formed tram ABS.

Figure 8 illustrates a second form of drawer unit wherein a plurality of drawers 10 have been assembled in the frame 70 and the lid 40 secured to the uppermost drawer 10, the latter being in an identical manner to that described above in reference to Figures 5 and 6. A saline bag 81 is shown as hanging from the lid 40. The curved recess 34 at the front of each of the drawers 10 ensures that the saline bag does not come into contact with the drawer 10 and is therefore decontaminated effectively.

Figure 9 illustrates the second form of drawer unit with a syringe 82 hanging from the lid 40.

The drawer units assembled from the drawer assembly may be used for holding a wide variety of items during bio-decontamination. If few drawers 10 are required to hold all of the items, the drawers 10 may be stacked in the first form of drawer unit, rather than all being inserted into the frame 70 in the second torm ct drawer unit. The size of the drawer unit can therefore be optimiseci.

The projections 21, gaps 20 and cross sectional shape of the bottom mesh 17 of the drawers 10 reduce the contact -17 -surface area between the medical items and the drawer assembly, thereby improving bio-deccntamination. Since large syringes 82 and medical bags 81 may not fit inside each drawer 10, the syringe(s) and/or medical bags may be hung from the lid 40 during bio-decontamination.

The possibility of mix-up between prescriptions is reduced by the use of the identification card. The features used to secure the lid 40 to the drawer 10, the drawers 10 to one another and the drawers 10 within the frame 70 ensure that if the drawer assembly is knocked over the medical items will not fall out.

Claims

-18 -CLAIMS: 1. A drawer assembly comprising; a plurality of drawers having drawer interlocking means for securing cne drawer to another drawer; and a frame comprising a plurality of pairs of rails for slidably receiving and supporting drawers; wherein the drawer assembly is assembleable to provide at least two different configurations of drawer unit; wherein in a first configuration of drawer unit at least one drawer is located directly on top of another drawer and is secured to the underlying drawer by the drawer interlocking means; and in a second configuration of drawer unit at least one of the drawers is supported on the rails in the frame.
2. The drawer assembly as claimed in claim 1 further comprising a lid comprising means for securing the lid to a drawer.
3. The drawer assembly as claimed in claim 2 wherein the lid securing means comprises a plurality of cantilever hooks.
4. The drawer assembly as claimed in any one of claims 2 and 3 wherein the lid further comprises at least one means for supporting an item external to the drawers.
5. The drawer assembly as claimed in any one of claims 2 to 4 wherein the lid further comprises an identification card holder.
6. The drawer assembly as claimed in claim 5 further comprising an identification card comprising a chemical -19 -composition which changes colour upon contact with a decontaminating gas.
7. The drawer assembly as claimed in any one of claims 2 to 6 wherein the lid securing means comprises complementary interlocking means on the lid and drawers.
8. The drawer assembly of any one of the preceding claims in which the drawers further comprise handles at the front of the drawers.
9. The drawer assembly as claimed in any one of the preceding claims wherein the drawer interlocking means comprise a plurality of cantilever hooks.
10. The drawer assembly as claimed in any one of the preceding claims wherein each drawer comprises four side walls projecting perpendicularly upwardly from a base.
11. The drawer assembly as claimed in claim 10 wherein at least a section of each of the side walls and lid comprise a mesh.
12. The drawer assembly as claimed in claim 10 or claim 11 wherein in the first configuration the plurality of cantilever hooks of the lid engage with a side wall of the drawer.
13. The drawer assembly as claimed in any one of claims 10 to 12 wherein the base is provided with an array of upstanding projections.

-20 -
14. The drawer assembly as claimed in claim 13 wherein each projection comprises a spike.
15. The drawer assembly as claimed in any one of the preceding claims wherein the frame comprises a top, a base, two opposing sides and a rear.
16. The drawer assembly as claimed in any one of the preceding claims wherein in the second configuration the drawers are slidably removed and inserted along the rails.
17. The drawer assembly as claimed in claims 15 or claim 16 wherein pairs of rails are provided at vertioal intervals on an inside of the opposing sides.
18. The drawer assembly as claimed in any one of the preceding claims wherein the rails further comprise a plurality of frame stops and the drawers further comprise catch means, and in the second configuration the catch means engage with the frame stops to secure the drawers in the frame.
19. The drawer assembly as claimed in claim 18 wherein the catch means comprise an indentation and the frame stops comprise a raised protrusion.
20. The drawer assembly substantially as hereinbefore described, with reference to and as shown in the accompanying figures.Amendments to the claims have been filed as follows CLAIMS: 1. A kit of parts comprising; a plurality of drawers having drawer interlocking means for securing one drawer to another drawer; and a frame comprising a plurality of pairs of rails for slidably receiving and supporting drawers; wherein the kit of parts is assembleable to provide at least two different configurations of drawer unit; wherein in a first configuration of drawer unit at least one drawer is located directly on top of another drawer and is secured to the underlying drawer by the drawer interlocking means; and in a second configuration of drawer unit the drawers are each supported by a pair of rails in the frame.o 2. The kit of parts as claimed in claim 1 further comprising r a lid comprising means for securing the lid to a drawer.O 3. The kit of parts as claimed in claim 2 wherein the lid securing means comprises a plurality of cantilever hooks.4. The kit of parts as claimed in any one of claims 2 and 3 wherein the lid further comprises at least one means for supporting an item external to the drawers.5. The kit of parts as claimed in any one of claims 2 to 4 wherein the lid further comprises an identification card holder.6. The kit of parts as claimed in claim 5 further comprising an identification card comprising a chemical composition which changes colour upon contact with a decontaminating gas.7. The kit of parts as claimed in any one of claims 2 to 6 wherein the lid securing means comprises complementary interlooking means on the lid and drawers.8. The kit of parts of any one of the preceding claims in which the drawers further comprise handles at the front of the drawers.9. The kit of parts as claimed in any one of the preceding claims wherein the drawer interlocking means comprise a plurality of cantilever hooks.10. The kit of parts as claimed in any one of the preceding claims wherein each drawer comprises four side walls o projecting perpendicularly upwardly from a base. rco 11. The kit of parts as claimed in claim 10 wherein at least C a section of each of the side walls and lid comprise a mesh.12. The kit of parts as claimed in claim 9 and claim 10, or claim 9 and claim 11, wherein in the first configuration the plurality of cantilever hooks of the lid engage with a side wall of the drawer.13. The kit of parts as claimed in any one of claims 10 to 12 wherein the base is provided with an array of upstanding projections.14. The kit of parts as claimed in claim 13 wherein each projection comprises a spike.15. The kit of parts as claimed in any one of the preceding claims wherein the frame comprises a top, a base, two opposing sides and a rear.16. The kit of parts as claimed in any one of the preceding claims wherein in the second configuration the drawers are slidably removed and inserted along the rails.17. The kit of parts as claimed in claims 15 or claim 16 wherein pairs of rails are provided at verticai intervals on an inside of the opposing sides.18. The kit of parts as claimed in any one of the preceding claims wherein the rails further comprise a plurality of v 15 frame stops and the drawers further comprise catch means, o and in the second configuration the catch means engage with r the frame stops to secure the drawers in the frame.O 19. The kit of parts as claimed in claim 18 wherein the catch means comprise an indentation and the frame stops comprise a raised protrusion.20. The kit of parts substantially as hereinbefore described, with reference to and as shown in the accompanying figures.