Title of Invention	DECONTAMINATION SYSTEM
Abstract	A decontamination system suitable for decontaminating items of equipment such as endoscopes, the system comprising: (I) a plurality of pre-clean wipes comprising moist fabric members for wiping an item to be decontaminated; (II) a two-part sterilant system comprising: (a) a first part comprising a first reagent in a carrier medium; and (b) a second part which is miscible with the first part and which comprises a second reagent in a carrier medium; wherein the first reagent and the second reagent will react when mixed to provide a sterilising composition; the first part being contained in a dispenser (2) whereby it may be dispensed as a fluid, and the second part being absorbed or impregnated in a plurality of sterilising wipes each of which comprises a fabric member in a sealed container (20); and (ill) a plurality of rinse wipes, each rinse wipe comprising a moist, sterile, fabric member in its own sealed container (40).

Title of Invention

DECONTAMINATION SYSTEM

Abstract

A decontamination system suitable for decontaminating items of equipment such as endoscopes, the system comprising: (I) a plurality of pre-clean wipes comprising moist fabric members for wiping an item to be decontaminated; (II) a two-part sterilant system comprising: (a) a first part comprising a first reagent in a carrier medium; and (b) a second part which is miscible with the first part and which comprises a second reagent in a carrier medium; wherein the first reagent and the second reagent will react when mixed to provide a sterilising composition; the first part being contained in a dispenser (2) whereby it may be dispensed as a fluid, and the second part being absorbed or impregnated in a plurality of sterilising wipes each of which comprises a fabric member in a sealed container (20); and (ill) a plurality of rinse wipes, each rinse wipe comprising a moist, sterile, fabric member in its own sealed container (40).

Full Text	DECONTAMINATION SYSTEM FIELD OF THE INVENTION The present invention relates to a decontamination system, notably to a system for ensuring that a medical device is •made safe after use on one patient prior to use on another patient. The-invention preferably makes use of chlorine dioxide (C102) as a sterilant. BACKGROUND TO THE INVENTION "Traditionally, the word ^decontamination' has been applied to those cleaning procedures - automatic and/or manual - that take place prior to -sterilisation. Recent documentation, "however y~ha-s ~reete-fi-Q-e:d -the -word -to apply to._the... whole series of procedures to ensure that a -device is made safe after use on one patient prior to us-e on a second. Decontamination can thus include cleaning-,., .disinfecting and- sterilising." This statement is ta&en from an article published in the ISSM (Institute of Sterile Service Managers) Journal, Vol. 5, No. 1 July-Septembej 2000. The statement helps to explain what the decontamination, process has come to mean in modern UK hospitals and goes on to refer to HTM203Q, which has been the driver for change in processing many types of medical instruments. The term ^decontamination' will be used herein to refer to the above redefinition, including cleaning and sterilising. Health Technical Memorandum (HTM) 2030 was introduced in 1993 and updated in 1997 and 2001 to improve the sterile processing performance of washer disinfectors. HTM2030 addresses the use of washer-disinfectors for instruments, many of which cannot be autoclaved, for example flexible endoscopes. In essence, it describes the need to wash instruments thoroughly before disinfection/sterilisation (by heat or by chemical); to be followed by the disinfection/sterilisation stage and to culminate, in the case of chemical disinfection, in the rinsing of the instrument. KTM2030 also addresses the need for the entire process to be recorded in a traceability and audit system. Two-part sterilising solutions are used in applications where the active sterilising ingredient is unstable over time. The solution is therefore prepared in situ shortly before it is to be used. A particularly important sterilising agent is chlorine dioxide, which may be formed from mixtures of various reagents including: chlorite and acid; chlorate, peroxide and acid; and chlorite, hypochlorite, and a suitable buffer. Chlorine dioxide has excellent sterilising and bactericidal properties, and oral ingestion in man and animals has been shown to be relatively safe. The cleaning of endoscopes and other medical equipment with suitable chlorine dioxide solutions is known. See, for example, European Patent Number 0 785 719 and United States Patent Numbers 5,696,046 and 6,007,772, the contents of which are hereby incorporated by reference. It is not always: convenient to mix up batches of solutions for use in sterilising equipment. For wiping down (rather than thoroughly cleaning inside and out) of endoscopes and 30 probes, wipes of alcohol, general-purpose detergent, or soapy water are generally used, but these are not as effective as chlorine dioxide. It is desirable to be able readily to make up small quantities of two-component sterilising agents when desired and to be able to make such agents up in a form in which they may be readily handled for a particular application. It is particularly desired to provide a decontamination system which meets the HTM2030 standard. SUMMARY OF THE INVENTION According to a first aspect of the present invention there is provided a decontamination system suitable for 10 decontaminating items of medical equipment such as endoscopes, the system comprising: (I) a plurality of pre-clean wipes comprising moist- fabric members for wiping an item to be decontaminated; (II) a two-part sterilant system comprising: . .Ji_^^i-- (a) a first part comprising a first reagent in a ....... carrier medium; and (b) a second part which is miscible with the first part and which comprises a second reagent in a carrier medium;..-, wherein "the first reagent and the .second reagent will 20 react when mixed to provide a sterilising composition; the first part being contained in a dispenser whereby it may be dispensed as a fluid, and the second part being absorbed or impregnated in a plurality of sterilising wipes each of which comprises a fabric member in a sealed 25 container; and (III) a plurality of rinse wipes, each rinse wipe comprising a moist, sterile, fabric member in its own sealed container. The system enables an item such as a flexible endoscope to be decontaminated without the use of a conventional washer-disinfector and, indeed, without a water supply. Each of the three wipes performs one stage of the decontamination process. The chemistry of the rinse wipe may be tailored or selected to give optimal surface rinsing for a given sterilant system. For example, the rinse wipe may include an agent for neutralising an active ingredient of the 5 sterilant system (^sterilising wipe')- In a preferred embodiment the 'sterilising wipe has ClOs as the active ingredient and ;the rinse wipe contains an antioxidant such as sodium thiosulphate for neutralising excess of C102. In prior art decontamination processes, ie, in washer-disinfectors, which use filtered mains water or water produced by reverse osmosis, or in a manual procedure in which tap water or bottled sterile water may be used, the water is indiscriminate to the chemistry employed in the disinfection process. Consequently the sterilant may be insufficiently removed by rinsing, or an undesirable excess of rinse water may be required. The fabric members may be formed from any suitable fabrics, 20 either woven t>r non-woven. They may be of natural or man-made fibres, for example polyester, cotton, cellulose or mixtures thereof. Other suitable fabrics will be well known to those skilled in the textile or fabric arts. The fabric members for each of the three types of wipe may be same or 25 different from each other. Pre-Cl«an Wip« The pre-clean wipe is moist and preferably provided in a sealed container. The container may be resealable, for example a canister with a lid, or a resealable sachet. In a preferred embodiment, each pre-clean wipe is provided in its own sachet which may be factory-sealed and disposed of after use. It is preferred that the pre-clean wipe contain additional components to improve its efficiency. The wipe may contain 5 at least one surfactant to promote wetting and/or dissolution of organic deposits. The surfactant may be a foaming surfactant such as a detergent or a soap, or a low-foam non-ionic surfactant such as Lanawet LF-6. The pre-clean wipe may advantageously contain other agents, for example one or 10 more selected from the following: enzymes for digesting or solubilising organic deposits, humectants, buffers, preservatives, corrosion inhibitors, solvents, or anti- . foaming agents. 15 St.eri.lant .Systam The term ^ fluid' is used herein to include liquids, foams., sprays, pastes, aerosols, powders, sols and gels. It is particularly preferred that the 'first part of the sterilant system is dispensed as a foam or a spray to facilitate its. coverage of a desired area of the fabric member. Optionally, the .dispenser may have a relatively large dispensing head, for supplying the fluid over all or a substantial part of a surface of .the fabric member. For example, the dispensing head may take the form of a rose or sprinkler with a multitude of small orifices to spread the fluid over the fabric member. The dispenser is preferably a pump-dispenser, notably a 30 trigger-operated dispenser, both for convenience and to facilitate the dispensing of metered quantities. However, other pump dispensers could be used, for example, a squeeze bottle with a suitable spray or foam nozzle. The invention will, for convenience, be described hereinafter with reference to the use of a trigger-operated dispenser, but it is to be understood that it is not limited to this embodiment. 5 By putting up the first part in a trigger-operated dispenser, small quantities may be readily dispensed without risk of spillage. Preferably the dispenser comprises a sprayer apparatus that provides the first part as a foam, so that it is at least partly form-retaining and can be readily seen and manipulated. We have also found that providing the first part in a foair. may have the beneficial effect of reducing the odour of chlorine dioxide when the wipe is activated. The invention will for convenience be described with reference to this preferred embodiment, but it will be understood that the invention is not limited to this embodiment. The trigger sprayer may include a mixing chamber to facilitate mizihg of the first part with air, for example as 20 described in United States patent number 5,337,929. By providing the second part absorbed in a fabric wipe, a sterilising wipe may readily be prepared by applying the first part to the fabric wipe. The user may fold the wipe or 25 rub two halves together to facilitate mixing. The wipes are particularly useful for cleaning, disinfecting, and sterilising surfaces and equipment, notably in a medical environment. The first part may include a coloured component so that a visual indication of the coverage of the wipe with the first part can be made. In a preferred embodiment, at least one of the first and second parts is provided with ar: indicator reagent that changes colour to show that sufficient mixing has taken place. Where the first part and the second part are of 5 different pE, the indicator may be a pH-sensitive indicator. Suitable indicators are well known to those skilled in the art, non-limiting examples including: phenol red, litmus, thymol blue, pentamethoxy red, tropeolin 00, 2,4-dinitrophenol, methyl yellow, methyl orange, bromophenol blue, tetrabromophenol blue, alizarin sodium sulphonate, ct-naphthyl red, p-ethoxychrysoidine, bromocresol green, methyl red, bromocrescl purple, chlorophenyl red, bromothymol blue, p-nitrophenol, azolitmin, neutral red, rosalic acid, cresol red, a-naphtholphthalein, tropeolin 000, phenolphthale'U^et- napntholbenzeiri, thymeIphthalein, nile blue, alizarin yellow, diazo violet, tropeolin "0, nitramin-e-, -pmrrer'-s- blue, trinitrobenzoic acid, and mixtures thereof. It is preferred that the indicator is selected so that both parts are separately colourl&ss 'and the -colour -develops -when the- two parts are mixed. Alternatively, ar additionally, one or more fluorescent additives may be included so that the mixture fluoresces to indicate mixing. Non-limiting examples of suitable 25 fluorescing agents include: 4-methylumbelliferone, 3,6-dihydrcxanthone, quinine, thioflavin, 1-napthol, harmine, coumarin, acridine orange, cotarmine, and mixtures thereof. The indicator (colour change or fluorescent) may be included 30 in either part. Preferred proportions by weight are about '0.1 to 10%, notably about 0.5 to 2%. The carrier mediums may be fluids such as liquids or sols, or they may be more form-retaining or viscous compositions such as gels or pastes. It is preferred that at least one reagent is present in an aqueous fluid, although other additives may of course be present. Preferably both reagents are put up in 5 aqueous fluids. The trigger-operated dispenser may be a conventional atomizer or foamer, or other manual pump in which the contents are expelled manually by operation of the trigger by the user. 10 Alternatively, the dispenser may contain a propellant to dispense the contents when operation of the trigger opens a valve, as is well known in applications such as shaving foam canisters and the like. Suitable dispensers will be well Icnown to those skilled in the art. 15 The preferred sterilising agent is chlorine dioxide, which may be formed from suitable known reagents. In a preferred embodiment one reagent is a chlorite (notably sodium chlorite) and the other is an acid, preferably with a buffer. 20 Suitable acids include lactic acid, citric acid, boric acid, phosphoric acid, acetic acid, sorbic acid, ascorbic acid, hydrochloric acid or mixtures thereof. In a preferred embodiment a mixture of acids is used, notably a mixture of citric, sorbic and boric acids. 25 A particularly preferred system is as described in EP 0 785 719, with the corrosion inhibitors optionally not included, and with other additives as desired for particular applications. In addition to suitable indicators, optional 30 additives include foam-promoting agents or stabilizers, humectants, essential oils and fragrances. Other sterilising agents may alsobe employed; for example chlorine or oxygen. Chlorine may be produced by reaction between a hypochlorite such as sodiurt: hypochlorite, and a suitable acid or buffer. Oxygen may be produced by reaction between a peroxide and a catalyst such as catalase, optionally in the presence of a buffer. For convenience hereinafter, the invention will be described with reference to chlorine dioxide as the sterilising agent. Suitable foam promoters will be well icnown to those, skilled in the art. Non-limiting examples include: sodium lauretli sulphate, ammonium lauryl sulphate, cocamide DBA, cocamidopropyl betaine, sodium lauryl sarcosinate, cocamidopropylamine oxide, monoethanolamine lauryl sulphate, cocamidopropyl hydr-oxysultaine, cocoyl sarcosinate. -Ani.onic, cationic, non-ionic., and amphoteric surfactants may be - "-•• emplo}7ed depending on the chemistry of the reagents. The foam -promoters are 'Selected to provide a stable foam structure. The foam promoter may -comprise from about 0.1 to 50% by weight of the first part, notably from about 1 to 10%, preferably -from about 3-to 6-%.-- ' - " Suitable foam stabilizers well known to those skilled in the art may also be used, in proportions similar to those for the foam-promoters. Non-limiting examples include: alkanolamides, for example monoethanolamides and diethanolamides, amine oxides, betaines, protein hydrolysates and cellulose derivatives such as carboxymethylcellulose. In a preferred embodiment, a humect ant is included in at least one of the first and second parts. Humectants serve to 30 reduce the rate of evaporation of components and improve product feel if direct skin contact is involved. We have found that the use of a humectant reduces the volatility of chlorine dioxide, which reduces the odour of chlorine dioxide and prolongs "he life of the activated mixture. Won-limit ing examples of suitable humectants include sodium lactate and polyols, for example glycerine, sorbitol, propylene glycol, diethylene glycol and ethylene glycol. The huiuectant may be 5 present in any desired amount, particularly from about 0.1 to 50% by weight, notably from about 0.5 to 10-%, preferably from about 1 to 3%. • Where one of the reagents is basic or oxidising, for example sodium chlorite, it is particularly preferred that this reagent is provided in the trigger dispenser rather than in the wipe, because such reagents may react with the fabric over time. Preferably the optional humectant is included in the first part, with the sodium chlorite or other first 15 reagent. The first and/or second part may further include a biocide to ensure that, in the event of poor mixing of the parts, a biocidal effect is still present. The first and/or second 20 part may also include a preservative. Equal weights of the first part and the second part may provide, when nixed, a sterilising composition having a pH of from 1.0 to 10.5, but it is preferred that the composition 25 has a pH of from 4.5 to 6.5 as this may result in a more stable compound. A plurality of fabric members may be provided in a single resealable container, for example a canister with a lid, or a 30 resealable sachet. In a preferred embodiment, each fabric member is provided in its own sachet which may be factory-sealed and disposed of after use. In a particularly preferred embodiment, each sealed sachet contains a single fabric wipe anc carries a removable adhesive label on its outer surface, the label containing informatiorj about the provenance of the wipe, for example its lot or batch number, its date of manufacture, or its expiry date. The label may 5 be affixed to E record sheet and used as part of an audit trail tc pro\Tide a record that an item of equipment has been properly decontaminated and the date on which this was done. In one embodiment the label adhesive and the record sheet are selected so that, though the label is releasably adhered to the sachet, it will become permanently adhered to the record sheet and cannot be removed intact. This arrangement helps provide a permanent validation record of the decontamination process. The record sheet may be provided in any convenient form, for example as a single sheet, as part of a loose^i&arf binder, or in an audit trail book. It will be understood that the sterilant system may optionally be provided as a stand-alone sterilant system, for use without the pre-clean wipe or the rinse wipe, or for use 20 as a replacement component in the decontaminant system. Rinse Wipe To maintain sterility of the wipes it is preferred that each 25 fabric member is provided in its own sachet which is factory-sealed and disposed of after use. The sachets may be gamma-irradiated before or after sealing to ensure sterility. In addition to water (preferably deionised water) , optional 30 components may comprise an antioxidant to neutralise oxidant in the sterilant system, a sequestering agent to sequester metal salts and improve cleaning, and a lubricant to provide visual enhancement, or "shine' to a decontaminated item such as an entioscope. A preservative may optionally be included, to eliminate roxic residues and enhance product stability prior to gamma-irradiation. 5 Other aspects and benefits of the invention will appear in the following specification, drawings and claims. BRIEF DESCRIPTION OF THE DRAWINGS The invent: ion will now be further described, by way of example, with reference to the following drawings in which: Figures 1 and 3 show views of alternative embodiments of pump dispensers for use in a decontamination system in accordance with embodiments of the present invention; Figures 2 and -4 are perspective views of a canister of sterilising wipes for use in a decontamination system in accordance with embodiments of the present invention; Figure 5 shows a decontamination system in accordance. with another embodiment of the invention-; . Figures 6 to 6 illustrate sachets from the system of Figure 5; and Figure 9 shows a record sheet for use with the decontamination system of Figure 5 in accordance with a further embodiment of the invention. DETAILED DESCRIPTION The pump dispenser 2 shown in Figure 1 is a trigger sprayer of a construction well known per se. The dispenser 2 comprises a body 24 connected to a sprayer head 4 by an internally screw-threaded connector ring 14. A spray nozzle 10 in the head is connected to an aqueous liquid 12 by means of a dip tube 6. A user dispenses the liquid 12 through the nozzle 10 by operation of a trigger 8. Rotation of the nozzle allows the user to dispense the fluid as either a spray of fine droplets or as a foam. In the present example, the liquid 12 (first part) comprises 0.75% of a first reagent (sodium chlorite), 3.0% foam 5 promoter (Cocamidopropyl Betaine). The remainder is deionised water. In this specification, all parts are by weight unless otherwise indicated. Operation of the trigger 8 dispenses the first part 12 as a foam. An alternative design of pump dispenser 2 is illustrated in Figure 3. The trigger B is formed integrally with the nozzle 10. Depressing the trigger 8 dispenses a portion of the fluid contents as a foam (referred to as the "Activator Foam' because it activates the sterilising powers of a sterilising wipe) . A protective cap 26 is provided to cover the nozzle 10 and trigger 8 when not in use. Turning now to :Figures 2 and 4, a scalable container 20 is also of a construction well known per se. The container 20 is a hollow cylinder fitted with a cap 22. The container 20 contains a roll of interleaved fabric sheets (or ^sterilising wipes') 18. In this example, the fabric sheets 18 are to be used as sterilising wipes, but it will be understood that the sheets 18 could also be used for other applications such as biocidal wound-dressings. The cap 22 has a central opening through which a tip of the central wipe 18 is disposed. By pulling the central wipe 18, a user may remove this wipe from the container, leaving the 30 next wipe in its place. A stopper 16 is provided on the cap 22 for releasably sealing the container 20. In this example, the wipes 18 are impregnated with an aqueous acid solution (second part). In t.his example, the acid solution comprises 0.5% citric acid, 0.05% sorbic acid, 0.05% boric acic. The solution also comprises 0.35% of a buffer (trisodium phosphate). The solution also comprises 0.25% 5 tr is odium citrate, 1.0% glycerine, 0.1% beuzotriazoie, 0.1% sodium molybdate and 0.3% sodium nitrate. The remainder is deionised water. The pump dispenser 2 and container 20 together comprise the 10 sterilant system. To activate a sterilising wipe, a user removes the wipe IB from the container 20, and applies a portion of foam from the dispenser 2 to the wipe 18. To facilitate mixing of the reagents in the foam and the wipe., the user may fold the wipe in half and crush or rub the...-3^. 15 folded wipe before opening it our. Preferably, one of the components is provided -with -a p-K—sen-s-iti-v-e indicator-'w-hich changes colour or becomes coloured when adequate mixing has % occurred, thereby indicating that sufficient ClOs has been generated in-the 'wipe. ._^_. .....^- Once the sterilising wipe has been activated, it may be used for a number of applications, including wiping surfaces and sterilising medical equipment such as endoscopes. The sterilant system illustrated in Figures 1-4 may be accompanied by a plurality of pre-clean wipes and a plurality of rinse wipes for treatment of an item to be de-contaminated respectively before and after treatment with a sterilising wipe. Each wipe may be made from the same fabric and may have the same dimensions. All of the wipes may be identical except for the fluid with which they are impregnated or soaked. In the preferred embodiment illustrated in Figures 5-8, each sterilising wipe is provided in its own sealed container 20, in this example a sachet. The disinfectant system comprises £ box 32 of pre-clean wipes in sachets 30, a box 28 of 5 sterilising wipes in sachets 20, and a box 34 of rinse wipes in sachets 40. Each sachet 20, 30, 40 is factory-sealed and may be disposed of after the wipe has been removed. The foam pump dispenser 2 is also provided in the box 28 of sterilising wipe sachets 20 Each sachet 20, 30, 40 is provided with a label 48 on the front, identifying what the relevant wipe is for. A label 50 on the back gives information about how the wipe is to be used and other product details. In this example, the pre-clean wipes contain the fluid formulation set forth in Table 1. Table Remove The trisodium citrate functions as a buffer; sodium benzoate functions as c preservative and corrosion inhibitor; monopropyiene glycol functions as a humectanr and soiubiliser; the enzymes promote digestion and solubiiizing 5 of organic deposits. The fluid formulation for the rinse wipes is given in Table Table Remove 10 RINSE WIPE FORMULATION TABLE 2 Sodium thiosulphate is -an antioxidant which helps to remove 15 traces of C102 from an item that has been sterilised. EDTA sodium salt is a seguestrant for removing dissolved metal salts and improving cleaning. The silicone emulsion functions as a lubricant to help 'shine' an item such as an endoscope and provide visual enhancement. The preservative 20 is added before the rinse wipes are gamma-irradiated, to help, reduce or eliminate toxic residue and enhance product stability prior to irradiation. To decontaminate an item (in this example an endoscope), a 25 user first opens a pre-clean wipe sachet 30 and takes out the pre-clean wipe. This wipe is used to remove soil and debris from the surface of the endoscope, in accordance with instructions on the label 50 of the sachet 30. After pre-cleaning, the pre-clean wipe is disposed of, and the user activates a sterilising wipe 16 by removing it from its sachet 20 and applying a metered dose of foam from the 5 dispenser 2 (in this example, two measures of foam activator are applied in. accordance with instructions on the label 50 on the back of the sachet 20) . After manipulating the wipe 18 to ensure mixing of the activator foam and the fluid in the wipe 18, the user waits about 15 seconds and then wipes 10 the surface of the endoscope for about 30 seconds. Finally, a rinse wipe sachet 40 is opened and a rinse wipe is used to wipe down the surface of the endoscope. The endoscope is now decontaminated and ready for use. Referring now to Figure B, a record sheet 36 is illustrated for use in proxiding a quality audit trail for an item of equipment decontaminated with an embodiment of the system of the present invention. The record sheet 36 may be loose or it may be bound in a book or file. The record sheet carries boxes or other defined locations for recordal of information relating to the: decontamination of the item. In the present example spaces are defined for recording the type of device .to be decontaminated, its reference number, its method of decontamination, and other details including the ID number of the patient on which the device has most recently been used, the date and time of decontamination, and the name and signature of the responsible person. The record sheet permits recording of the pre-clean wipe process, the 'sterilising process, and the rinse wipe process. It also provides information as to the immediate destination of the decontaminated item - either for use with the patient or return to storage. For each decontamination history of each device on the record sheet 36 there is provided a space 42 for receiving £ record book label 38 from the back of the sterilising wipe sachet 20. The user peels the sticky label 38 off the sachet and 5 affixes it in the space 42 as proof that the sterilising wipe IB has been used, and marks adjacent boxes to confirm that "he wipe IE has been properly activated by following the specified steps. If the decontaminated device is to be returned for use on the specified patient, this information is recorded on zhe record sheet. Alternatively, i'f the device is to be returned to storage, a second sticky label, the 'patient's notes label7 46 is peeled off the sterilising wipe sachet 20 and affixed in another box 44 on the record sheet 36. This embodiment of-the invention therefore provides a traceability system which uses the sterilising wipe sachet "20 as evidence that the wipe -has -been used as a single-use process, uniquely identified to a specific instrument -at a specific time and date. EXPERIMENTAL RESULTS Experiment 1 Sterising wipes 18 in accordance .with one aspect of the 25 invention were tested and compared with conventional wipes saturated with isopropanol (IPA), a general-purpose detergent, and sterile deionised water. The test method to evaluate effectiveness of the wipes in 30 killing/removing test organisms dried onto test surfaces, involved the following steps. 1. Mark out a six inch (30.5 cm) square test area on the test surface. 2. Inoculate the test surface with 0.5 ml of test organism suspension. 3. Spread the inoculum over the test area using a plastic spreader. 4. Allow the inoculum to dry (about 30 minutes) . . Don a pair of disposable plastic gloves. 6. Prepare a ClOj wipe in accordance with the invention, using a prescribed mixing time. 7. Wipe the test area for the prescribed wiping time. 8. Place the wipe in 10 ml of universal neutraliser in a Universal bottle (Test Suspension A) . Vortex stir to release organisms. 9. Wipe the entire test area with a cotton-tipped swab (thoroughly/10 times) . 10. Dip the swab into 10 ml of universal neutraliser in a Universal bottle after each sampling of the test area and rotate the swab against the inner wall of the bottle to release organisms (Test Suspension B) . 11. Prepare 5 serial deci-dilutions of Test Suspension A and Test Suspension B in diluent. 12. Inoculate 0.5 ml of each dilution onto a culture plate and spread using a plastic spreader. Incubate rne plates and ao a viable count. 13. Calculate iogaD reductions achieved from the difference 5 in the initial inoculum and the number of test organisms recovered after disinfection with a C102 wipe. Test variables were as follows. Test Surface A flat stainless steel instrument tray. Test Organism -:_ - Spores of Bacillus subtilis var.niger'UCTC 1CTC73 freshly prepared by the method of Beeby & Whitehouse. The test surface was inoculated with 1 X 10E spores Suspending Fluid 25 Sterile deionised water. 1 Disinfectant Concentrations i 1. 200 ppm C102 (notional) ! 2. 300 ppm C102 (notional). Mixing Times 15 4 30 seconds. Wipinq Times 15 4 30 4 60 seconds Controls 1. 1% Hospec general purpose neutral liquid detergent (Young's Detergents)/Kimcare Medical Wipes (Kimberly-Clark). 2. Sterets Alcowipe: 70% I PA (Seton Prebtales Ltd). 3. Sterile deionised water: Kimcare Medical Wipes (Kimberly-Clark). Resulrs are given in Table 1. Table Remove TABLE 1 VC = Viable Count Interpretation of Results 1. Washing/wiping with water, neutral detergent '(1% Bospec), or alcohol (70% 1PA) were ineffective 2. For the notional 200 ppm C1Q2 wipes the best results were obtained with a mixing time of 15 seconds and a wiping time of 60 seconds. 3. For the notional 3.0"0 ppm CIDa wipes the "best results, ~ were obtained with a mixing time of 30 seconds and a wiping time of 60 seconds. 4. Results for 200 ppm C102 (notional) were surprisingly better than results for 300 ppm (notional) , except for mixing times of 30 seconds combined with wiping times of -at least 30 seconds. 5. A wiping time of 60 seconds achieved better results than a wiping time of 30 seconds, which in turn achieved better results than a wiping time of 15 seconds. 6. Both C102 concentrations achieved good results after a wiping time of 60 seconds. The test surface was inoculated with 1 x 10s spores. After using the C102 wipes, surface 30 counts were reduced to 10 and 29 (200 ppm C102) and to 160 and 20 (300 ppin C102) . 7. A wipe containing 200 or 300 ppm may be useful, as may mixing times of 15 or 30 seconds (or, clearly, any intermediate times). However, it is preferred that wiping rimes longer than 15 seconds are employed. These results were obtained using bacterial spores. It is to be expected that a vegetative bacterium such as MRSA will be much more sensitive, so that lower ClOj concentrations and/or shorter mixing or wiping times may be effective against such bacteria. Further experiments (2-4) were carried out using 41 gsm spunlace sheets comprised of 50.5% wood pulp and 49.5% PET. The sheets' dimensions were 160 mm x 180 mm x 0.36 mm. In each experiment the wipes each contained 3 ml of Solution A (formulated as set forth below) , made by treating a canister of 50 wipes with 150 ml of Solution A. Each wipe was activated with 1.5 ml of Solution B (formulated as set forth below) from a foam dispenser. Solution A (Wipe) Formulation: Table Remove Solution B (Foam) Formulation: Table Remove Experiment 2 A study was carried out to compare the effectiveness of (a) C102 wipes in accordance with the invention (b) a 70% IPA wipe (c) a neutral detergent wipe and (d) a water wipe in removing and/or killing (1) B. subtilis spores, and (2) P. aeruginosa cells dried onto the insertion tube of E flexible endoscope . Wipes were prepared fresh as required by squirting foam onto a wipe and then scrunching the wipe with the fingers to mix the reagents to form EXPERIMENT 2 Test organisms B. subtilis NCTC 10073 spores A suspension containing approximately 108 spores/ ml was prepared by the method of Beeby & Whitehouse. A 1 in 10 dilution in sterile distilled water was prepared to produce a suspension containing approximately 107 spores/ ml. P. aeruginose biCTC 6749 A culture containing approximately 10s cells/ ml was prepared by inoculating a tube of nutrient broth and incubating for 18 h at 37° C. Insertion tube used in Experiment 2 The insertion tube was 1 metre long, in good condition, with clear markings. The test site used was the 10 cm section between the 30 and 40 markings. Test Method 1. Immerse a cotton-tipped swab into a suspension of spores or vegetative cells. 2. Inoculate entire surface area of test sire with the suspension. Repeat several times. Regarding £. .subtilis spores, assume that (1) the volume of inoculum = 0.1 ml, and [2] the mortality rate on drying out is sero. Hence the 5 viable count of 'the inoculum - approximately 10e spores. Regarding P* aeruginosa .cells, assume that (1) the volume of inoculum = C.I ml, and (2) the mortality rate on drying out is 1 log. Hence the viable count of the inoculum = approximately 10e cells. 3. Place inoculated insertion tube across the top of an empty discard jar with the 10 cm test site resting over the centre of the jar. Allow inoculum to dry -.out (approximately 30 minutes). 4. Dor. pair ..of disposable plastic gloves. • Jaorr 5. Prepare a Wipe: C1Q2 (scrunch time = 15 sec) , IPA, Hospec or water. • ; 6. Wipe test site for the prescribed wipe time (30 sec) as follows: Wrap wipe loosely around .the insertion tube and then wipe up and down the test site repeatedly. 7. Place the wip.e in 20 ml of universal neutraliser in. .a Universal bottle. Vortex stir to release recovered spores/ cells (Test Suspension A). 8. Swab entire test site with a cotton-tipped swab. Dip swab into 10 ml of universal neutraliser in a Universal bottle and rotate swab against the inner wall of the bottle to release recovered spores/ cells. Repeat 10 times then break off cotton-tip of swab and leave in the neutraliser. Vortex stir to release recovered spores/ cells (Test Suspension B). 9. Prepare 5 serial deci-dilutions of Test Suspension A and Test Suspension B in diluent. 10. inoculate 0.5 ml of each dilution onto a culture plate and spread using a plastic spreader. Incubate plates. Viable count. 11. Calculate Iog10 reductions achieved from the difference in the number of spores or cells inoculated onto the test site (approximately 106) and the number recovered after cleaning and/or disinfection. Wipes used In Experiment 2 1. C102 Wipe (scrunch time = 15 seconds). 2. 70% IPA wipe: Azowipe (Vernon Carus). 3. Hospec wipe: Kimberley Clark Medical Wipe immersed in 1% Hospec and then squeezed to remove excess solution. 4. Water wipe: Kimberley Clark Medical Wipe immersed in sterile water and then squeezed to remove excess water. EXPERIMENT 2 - EZSDLTS Table 2 Table Remove Table 3 a Viable count in Table 1 x 20 (0.5 ml of 10 ml neutraliser plated out) . 2 Viable count in Table 1 x 40 (0-5 ml of .20 -.ml neutraliser plated out) . EXPERIMENT 2 - CONCLUSIONS 1. C102 wipes were completely effective against both B. subtilis spores and P. aeruginosa cells. No spores or cells were recovered in duplicate experiments. 15 2. IPA wipes exhibited good activity against P. aeruginosa cells but did not eliminate all of the test cells - 40 viable cells were recovered from the test site on the insertion tube. 3. IPA wipes were ineffective against B. subtilis spores. 20 IPA proved less effective than 1% Hospec or water which may be attributable to the coagulant properties of alcohol ('fixing spores on the test site) . . Wipes saturated with 1% Hospec were ineffective against either B. suJbtilis spores or P. aeruginosa cells. 5 5. Wipes saturated with water were ineffective against either B. snbtilis spores or P. aeruginosa cells. Experiment 3 EVALUATION OF SEC EFFECTIVENESS OF C1O2 WIPES IN KILLING/ REMOVING METEICILLIN RESISTANT STAPESLOCOCCTTS ADREUS (MRSA) DRIED ONTO A STAINLESS STEEL TEST SURFACE Test Method The following test method was used to evaluate the effectiveness of ClOs Wipes in killing/ removing test-organisms dried onto test surfaces. The test method involves the following steps: 1. Mark out an 18 inch (457.2 mm) square on the test surface. 2. Inoculate test surface with 4.5 ml of test organism suspension. 3. Spread inoculum over 18 inch (457.2 mm) square test area using a plastic spreader. 4. Allow inoculum to dry (30-60 minutes). 5. Don pair of disposable plastic gloves. 6. Prepare a C1C>2 Wipe using the prescribed scrunch time (15 seconds) . 7. Wipe test area for the prescribed wipe time (30 seconds). 8. Place the CIO; Wipe in 20 ml of universal neutraliser in a universal bottle. Vortex stir to release organisms. (Test Suspension A). B. Swab entire rest area with a cotton-tipped swab. Dip swab into 10 ml of universal neutraliser in a universal bottle and rotate cotton-tip againsr the inner .wall of the bottle to release organisms. Repeat 10 times. Finally, snap off cotton-tip into the neutraliser. Vortex stir .to release organisms. (Test Suspension B). 10 10. Prepare 5 serial deci-dilutions of Test Suspension -A and Test Suspension B in diluent. 11. Inoculate 0.5 ml of each dilution onto a culture plate and spread using a plastic spreader. Incubate plates. Viable count. 15 12. Calculate logio reductions achieved from the difference in the initial inoculum and the number of test organisms "" recovered after cleaning/ disinfection with a C1O2 Wipe. 13. Repeat above using control wipes (70% IPA, 1% Hospec '& sterile -water) . Variables selected, in Experiment 3 Test surface A flat stainless steel laboratory bench. Test organism Methicillin Resistant Staphylococcus aureus (MRSA) : a 30 clinical isolate from the Royal Preston Hospital. Inoculum The rest surface was inoculated with >10S bacterial cells: 4.5 ml of an overnight culture in Nutrient Broth. 5 Suspending fluid Nutrient Broth 10 Scrunch time 15 seconds Wipe time 30 seconds Controls 1. 70% IPA wipe: Azowipe (Vernon Carus). 2. 1% Hospec general purpose neutral liquid detergent (Young's Detergents) / Kimcare Medical Wipe (Kimberly-Clark). The wipe was immersed in 1% Hospec and then squeezed with the fingers to remove excess fluid. 3. Sterile deionised water / Kimcare Medical Wipe (Kimberly-Clark) . The wipe was immersed in water and then squeezed with the fingers to remove excess fluid. Results Table Remove Table 4 Table Remove Table 5 a Viable Count in Table 1 x 20 (0.5 ml of 10 ml neutraliser plated out) . 2 Viable Count in Table 1 x 40 (0.5 ml of 20 ml neutraliser plated out) . Interpretation of results 1. Wiping with a CIO; Wipe for 30 seconds was completely effective. No test organisms were recovered from either the test surface or the wipes in duplicate experiments. 2. Wiping the test surface with a 70% IPA wipe (Azowipe) for 30 seconds was ineffective. This could be due to: (a) an exposure time of 30 seconds was not long enough to kill the MRSA (b) the IPA evaporated off the test surface before the minimum exposure time required to kill the MRSA (c) the volume of IPA on the wipe was insufficient to deal with the >10S MRSA dried onto the 18 inch test surface (d) a combination of the above. 3. Only 360 test organisms were recovered from the Azowipe. This could be due to : (a) entrapment of test organisms in the fibres (b) incomplete/ slow neutralisation of the residual IPA on the wipe by the neutraliser (c) a combination of the above 4. Wipes saturated-with either 1% Hospec or sterile water were ineffective. Experiment 4 This experiment was carried out to evaluate the effectiveness of C102 Wipes in killing/ removing spores of Bacillus subtilis var. niger NCTC 10073 dried out for 24 h at room temperature on a stainless steel test surface. Test Method 1. Mark out a 12 inch (304.8 ram) square on the zesr surface. 2 . Inoculare rest surface with 1. 0 ml of aqueous spore suspension. 2. Spread inoculum over 12 inch (304. B mm) square test area using a plastic spreader. 4. Allow inoculum, to dry out naturally at room temperature for 24 h. 5. Don pair of disposable plastic gloves. 6.. 'Prepare a C102 Wipe using-the prescribed .scrunch time. (15 seconds.).. • " '•• • ... - . j^,. 1. Wipe test area for the prescribed wipe time (30 seconds) . 8. Place the C1C>2 Wipe in 20 ml of universal neutraliser in a universal bottle. Vortex stir to release organisms. (Test Suspension A). • • ~ "~ B, Swab entire test area with a cotton-tipped swab. Dip swab into 10 ml of universal neutraliser in a universal bottle and rotate cotton-tip against the inner wall of the bottle to release organisms. Repeat 10 times. Finally, snap off cotton-tip into the neutraliser. Vortex stir to release organisms. .(Test Suspension B) . 10. Prepare 5 serial deci-dilutions of Test Suspension A and Test Suspension B in diluent. : 11. Inoculate 0.5 ml of each dilution onto a culture plate and spread using a plastic spreader. 12. Repeat above using a control wipe (a Medical Wipe saturated with sterile water). 13. Incubate plates. Viable count. 14. Calculate logic reductions achieved using the C102 Wipe from the difference in viable count obtained using the C.102 Wipe and the control wipe. Variables selected in Experiment 4 Test surface A flat stainless steel instrument tray. Test organism Bacillus subtilis var. niger NCTC 10073. A spore suspension was prepared by the method of Beeby & Whitehouse. 15 Inoculum The test surface was inoculated with (a) 106 spores, and (b) 108 spores. 20 Suspending fluid Deionised water. Drying time The inoculated instrument tray was allowed to dry out naturally at room temperature for 24 h in a dark cupboard. Scrunch time 15 seconds. Wipe rime 30 seconds Conrroi 1. Sterile deionised water / Kimcare Medical Wipe (Kimberly-Clark) . The wipe was immersed in water and then 10 squeezed with the fingers to remove excess fluid. Results Table Remove Table Remove Table 7 1 Viable Count in Table 1 x 20 (0.5 ml of 10 ml neutraliser plated out). 2 Viable Count in Table 1 x 40 (0.5 ml of 20 ml neutraliser plated out). Interpretation of results 1. Spores dried out for 24 h at room temperature on a stainless steel test surface were not easy to dislodge using a Medical Wipe saturated with deionised water. With the 106 inoculum the recovery was 4.0-8.4 x 103 spores leaving 2-3 logio spores on the surface (assuming no mortality). With the 106 inoculum the recovery was 1.3 -7.6 x 106 spores leaving 1- 2 logic spores on the surface. 2. C102 Wipes were effective in killing/ removing spores dried out for 24 h at room temperature on the stainless steel test surface. With the 106 inoculum, no spores were recovered from either the surface or wipe which represents a 3-4 Iog10 reduction on both the surface and wipe. With the 108 inoculum, a 2-2 logic, reduction of spores was achieved on the surface anc a 3-4 logic reduction on the wipe. Thus., the invention provides e decontamination system which 5 can be prepared in sitv and which provides bactericidal, fungicidal, virucidal, and sporicidal fabrics. The system is particularly useful for sterilising wipes and for the dressing of wounds and ulcers. It is appreciated that certain features of the invention which are, for clarit}-7., described in the -.context of separate embodiments., may also be provided in combination in a single embodiment. Conversely/ various_ features of the. invention which are, for brevity, described -in .the context of -a single embodiment, .may. also 'be provided separately..,-— or-, in -any suitable combicatipn. It is to be rec^ognised that _various alterations, modifications, arid/or additions may be introduced into the constructions and arrangements of parts described above without departing from the ambit of the present invention. As used herein, the indefinite articles ^ar and 'an' connote ^one or more' unless the context requires otherwise. The disclosures in United Kingdom patent application No. 0410204.2, from which this application claims priority, and in the abstract accompanying this application are incorporated herein by reference. CLAIMS 1. A decontamination system suitable-for decontaminating items of medical equipment such as endoscopes, the system 5 comprising: (I) a plurality of pre-clean wipes comprising moist fabric members for wiping an item to be decontaminated; (II) a two-part sterilant system comprising: (a) a first part comprising a first reagent in a carrier medium; and (b) a second part which is miscible with the first part and which comprises a second reagent in a carrier medium; •wherein the first reagent and the second reagent will react when mixed to provide a sterilising composition; the first part being contained in a dispenser whereby it may be dispensed as a fluid, and the second part being absorbed or impregnated in a plurality of sterilising wipes each of which comprises a fabric member in a sealed container; and (III) a plurality of rinse wipes, each rinse wipe comprising a moist, sterile, fabric member in its own sealed container. 2. A decontamination system according to claim 1, further comprising a record sheet for recording information concerning decontamination of an item of equipment. 3. A decontamination system according to claim 2, wherein each sterilising wipe is provided in its own sealed container and each of said containers carries on an outer surface a removable adhesive label which provides information about the contents of the container including at least one of: the lot or batch number; the date of manufacture; a use-by or expiry date; anc wherein said record sheet includes a space for receiving said label. 4. A decontamination system according tc claim 3, wherein said record .sheet comprises a logbook which carries predefined spaces for receiving adhesive labels from each container for said sterilising wipes. 5. A decontamination system according to any preceding claim., wherein said first part includes a foam promoter and is contained in a trigger-operated foam dispenser. 6. A -decontamination -system according TO any -preceding5*** claim, wherein at least one of said first part and said second part includes an indicator reagent that changes colour when the parts are mixed together. 7. A decontamination system according to claim • "67"' wherein said first part and .said second part have a different pH and wherein the indicator reagent changes colour in response to a change in pH when the parts are mixed. 8. A decontamination system according to any preceding claim, wherein one of said first part and said second part comprises a solution containing sodium chlorite or sodium chlorate and the other comprises an acidic solution. 9. A decontamination system according to claim 8, wherein the acidic solution comprises a solution of citric acid, sorbic acid and boric acid. 10. A decontamination system according to any preceding claim, wherein said first part further comprises from O.I to 50% w/w of at least one foam promoter. 11. A decontamination system according to any preceding claim, wherein one of said first part and said second part further comprises from 0.1 to 50% w/w of a humectant. 12. A decontamination system according to any preceding claim, wherein when equal weights of said first part and the second part are mixed they provide a sterilising composition having a pH of from 4.5 to 6.5. 13. A decontamination system according to claim 8, wherein said first part comprises said solution of sodium chlorite or sodium chlorate. 14. A decontamination system according to any preceding claim, wherein said pre-clean wipes contain at least one surfactant. 15. A decontamination system according to any preceding claim, wherein said pre-clean wipes contain at least one enzyme for digesting or solubilizing organic deposits. 16. A decontamination system according to any preceding claim, wherein said rinse wipes include an agent for neutralising an active ingredient of the sterilant system. 17. A decontamination system according to any of claims 1-30 15, wherein said sterilant system will produce an oxidising agent when the first and second parts are mixed, and wherein said rinse wipes contain an antioxidant to at least partly neutralise or reduce said oxidising agent. IB. A decontamination system according to claim 17, wherein said oxidising agent is CIO: and said antioxidar.t is sodium thiosnlphate. 19. A decontamination system according to any preceding claim, wherein said rinse wipes further contain at least one component selected from: a sequestering agent,- a lubricant, and a preservative. 20. A decontamination S3^steiri according to any preceding claim, wherein each pre-clean wipe, each sterilising wipe, and each rinse wipe is provided in its own sealed sachet.

Full Text

DECONTAMINATION SYSTEM FIELD OF THE INVENTION
The present invention relates to a decontamination system, notably to a system for ensuring that a medical device is •made safe after use on one patient prior to use on another patient. The-invention preferably makes use of chlorine dioxide (C102) as a sterilant.

BACKGROUND TO THE INVENTION
"Traditionally, the word ^decontamination' has been applied to those cleaning procedures - automatic and/or manual - that
take place prior to -sterilisation. Recent documentation,
"however y~ha-s ~reete-fi-Q-e:d -the -word -to apply to._the... whole series of procedures to ensure that a -device is made safe after use on one patient prior to us-e on a second. Decontamination can thus include cleaning-,., .disinfecting and- sterilising." This
statement is ta&en from an article published in the ISSM
(Institute of Sterile Service Managers) Journal, Vol. 5, No. 1 July-Septembej 2000. The statement helps to explain what the decontamination, process has come to mean in modern UK hospitals and goes on to refer to HTM203Q, which has been the
driver for change in processing many types of medical
instruments. The term ^decontamination' will be used herein to refer to the above redefinition, including cleaning and sterilising.
Health Technical Memorandum (HTM) 2030 was introduced in 1993 and updated in 1997 and 2001 to improve the sterile processing performance of washer disinfectors. HTM2030 addresses the use of washer-disinfectors for instruments,

many of which cannot be autoclaved, for example flexible endoscopes. In essence, it describes the need to wash instruments thoroughly before disinfection/sterilisation (by heat or by chemical); to be followed by the
disinfection/sterilisation stage and to culminate, in the case of chemical disinfection, in the rinsing of the instrument. KTM2030 also addresses the need for the entire process to be recorded in a traceability and audit system.
Two-part sterilising solutions are used in applications where the active sterilising ingredient is unstable over time. The solution is therefore prepared in situ shortly before it is to be used. A particularly important sterilising agent is chlorine dioxide, which may be formed from mixtures of
various reagents including: chlorite and acid; chlorate,
peroxide and acid; and chlorite, hypochlorite, and a suitable buffer. Chlorine dioxide has excellent sterilising and bactericidal properties, and oral ingestion in man and animals has been shown to be relatively safe.

The cleaning of endoscopes and other medical equipment with suitable chlorine dioxide solutions is known. See, for example, European Patent Number 0 785 719 and United States Patent Numbers 5,696,046 and 6,007,772, the contents of which
are hereby incorporated by reference.
It is not always: convenient to mix up batches of solutions for use in sterilising equipment. For wiping down (rather than thoroughly cleaning inside and out) of endoscopes and 30 probes, wipes of alcohol, general-purpose detergent, or soapy water are generally used, but these are not as effective as chlorine dioxide. It is desirable to be able readily to make up small quantities of two-component sterilising agents when

desired and to be able to make such agents up in a form in which they may be readily handled for a particular application. It is particularly desired to provide a decontamination system which meets the HTM2030 standard.
SUMMARY OF THE INVENTION
According to a first aspect of the present invention there is provided a decontamination system suitable for 10 decontaminating items of medical equipment such as endoscopes, the system comprising:
(I) a plurality of pre-clean wipes comprising moist-
fabric members for wiping an item to be decontaminated;
(II) a two-part sterilant system comprising: . .Ji_^^i--
(a) a first part comprising a first reagent in a .......
carrier medium; and
(b) a second part which is miscible with the first part and which comprises a second reagent in a carrier medium;..-, wherein "the first reagent and the .second reagent will 20 react when mixed to provide a sterilising composition;
the first part being contained in a dispenser whereby it may be dispensed as a fluid, and the second part being absorbed or impregnated in a plurality of sterilising wipes each of which comprises a fabric member in a sealed 25 container; and
(III) a plurality of rinse wipes, each rinse wipe
comprising a moist, sterile, fabric member in its own sealed
container.
The system enables an item such as a flexible endoscope to be decontaminated without the use of a conventional washer-disinfector and, indeed, without a water supply. Each of the three wipes performs one stage of the

decontamination process. The chemistry of the rinse wipe may be tailored or selected to give optimal surface rinsing for a given sterilant system. For example, the rinse wipe may include an agent for neutralising an active ingredient of the 5 sterilant system (^sterilising wipe')- In a preferred embodiment the 'sterilising wipe has ClOs as the active ingredient and ;the rinse wipe contains an antioxidant such as sodium thiosulphate for neutralising excess of C102.
In prior art decontamination processes, ie, in washer-disinfectors, which use filtered mains water or water produced by reverse osmosis, or in a manual procedure in which tap water or bottled sterile water may be used, the water is indiscriminate to the chemistry employed in the
disinfection process. Consequently the sterilant may be
insufficiently removed by rinsing, or an undesirable excess of rinse water may be required.
The fabric members may be formed from any suitable fabrics, 20 either woven t>r non-woven. They may be of natural or man-made fibres, for example polyester, cotton, cellulose or mixtures thereof. Other suitable fabrics will be well known to those skilled in the textile or fabric arts. The fabric members for each of the three types of wipe may be same or 25 different from each other.
Pre-Cl«an Wip«
The pre-clean wipe is moist and preferably provided in a sealed container. The container may be resealable, for
example a canister with a lid, or a resealable sachet. In a preferred embodiment, each pre-clean wipe is provided in its own sachet which may be factory-sealed and disposed of after

use.
It is preferred that the pre-clean wipe contain additional components to improve its efficiency. The wipe may contain 5 at least one surfactant to promote wetting and/or dissolution of organic deposits. The surfactant may be a foaming surfactant such as a detergent or a soap, or a low-foam non-ionic surfactant such as Lanawet LF-6. The pre-clean wipe may advantageously contain other agents, for example one or 10 more selected from the following: enzymes for digesting or solubilising organic deposits, humectants, buffers, preservatives, corrosion inhibitors, solvents, or anti- . foaming agents.

15 St.eri.lant .Systam
The term ^ fluid' is used herein to include liquids, foams., sprays, pastes, aerosols, powders, sols and gels. It is particularly preferred that the 'first part of the sterilant
system is dispensed as a foam or a spray to facilitate its.
coverage of a desired area of the fabric member. Optionally, the .dispenser may have a relatively large dispensing head, for supplying the fluid over all or a substantial part of a surface of .the fabric member. For example, the dispensing
head may take the form of a rose or sprinkler with a
multitude of small orifices to spread the fluid over the fabric member.
The dispenser is preferably a pump-dispenser, notably a 30 trigger-operated dispenser, both for convenience and to
facilitate the dispensing of metered quantities. However, other pump dispensers could be used, for example, a squeeze bottle with a suitable spray or foam nozzle. The invention

will, for convenience, be described hereinafter with reference to the use of a trigger-operated dispenser, but it is to be understood that it is not limited to this embodiment. 5
By putting up the first part in a trigger-operated dispenser, small quantities may be readily dispensed without risk of spillage. Preferably the dispenser comprises a sprayer apparatus that provides the first part as a foam, so that it
is at least partly form-retaining and can be readily seen and manipulated. We have also found that providing the first part in a foair. may have the beneficial effect of reducing the odour of chlorine dioxide when the wipe is activated. The invention will for convenience be described with reference to
this preferred embodiment, but it will be understood that the invention is not limited to this embodiment.
The trigger sprayer may include a mixing chamber to facilitate mizihg of the first part with air, for example as 20 described in United States patent number 5,337,929.
By providing the second part absorbed in a fabric wipe, a sterilising wipe may readily be prepared by applying the first part to the fabric wipe. The user may fold the wipe or 25 rub two halves together to facilitate mixing. The wipes are particularly useful for cleaning, disinfecting, and sterilising surfaces and equipment, notably in a medical environment.
The first part may include a coloured component so that a
visual indication of the coverage of the wipe with the first part can be made.

In a preferred embodiment, at least one of the first and second parts is provided with ar: indicator reagent that changes colour to show that sufficient mixing has taken place. Where the first part and the second part are of 5 different pE, the indicator may be a pH-sensitive indicator. Suitable indicators are well known to those skilled in the art, non-limiting examples including: phenol red, litmus, thymol blue, pentamethoxy red, tropeolin 00, 2,4-dinitrophenol, methyl yellow, methyl orange, bromophenol
blue, tetrabromophenol blue, alizarin sodium sulphonate, ct-naphthyl red, p-ethoxychrysoidine, bromocresol green, methyl red, bromocrescl purple, chlorophenyl red, bromothymol blue, p-nitrophenol, azolitmin, neutral red, rosalic acid, cresol red, a-naphtholphthalein, tropeolin 000, phenolphthale'U^et-
napntholbenzeiri, thymeIphthalein, nile blue, alizarin yellow, diazo violet, tropeolin "0, nitramin-e-, -pmrrer'-s- blue, trinitrobenzoic acid, and mixtures thereof. It is preferred that the indicator is selected so that both parts are separately colourl&ss 'and the -colour -develops -when the- two
parts are mixed.
Alternatively, ar additionally, one or more fluorescent additives may be included so that the mixture fluoresces to indicate mixing. Non-limiting examples of suitable 25 fluorescing agents include: 4-methylumbelliferone, 3,6-dihydrcxanthone, quinine, thioflavin, 1-napthol, harmine, coumarin, acridine orange, cotarmine, and mixtures thereof.
The indicator (colour change or fluorescent) may be included 30 in either part. Preferred proportions by weight are about '0.1 to 10%, notably about 0.5 to 2%.
The carrier mediums may be fluids such as liquids or sols, or

they may be more form-retaining or viscous compositions such as gels or pastes. It is preferred that at least one reagent is present in an aqueous fluid, although other additives may of course be present. Preferably both reagents are put up in 5 aqueous fluids.
The trigger-operated dispenser may be a conventional atomizer or foamer, or other manual pump in which the contents are expelled manually by operation of the trigger by the user. 10 Alternatively, the dispenser may contain a propellant to
dispense the contents when operation of the trigger opens a valve, as is well known in applications such as shaving foam canisters and the like. Suitable dispensers will be well Icnown to those skilled in the art. 15
The preferred sterilising agent is chlorine dioxide, which may be formed from suitable known reagents. In a preferred embodiment one reagent is a chlorite (notably sodium chlorite) and the other is an acid, preferably with a buffer. 20 Suitable acids include lactic acid, citric acid, boric acid, phosphoric acid, acetic acid, sorbic acid, ascorbic acid, hydrochloric acid or mixtures thereof. In a preferred embodiment a mixture of acids is used, notably a mixture of citric, sorbic and boric acids. 25
A particularly preferred system is as described in EP 0 785 719, with the corrosion inhibitors optionally not included, and with other additives as desired for particular applications. In addition to suitable indicators, optional 30 additives include foam-promoting agents or stabilizers,
humectants, essential oils and fragrances. Other sterilising agents may alsobe employed; for example chlorine or oxygen. Chlorine may be produced by reaction between a hypochlorite

such as sodiurt: hypochlorite, and a suitable acid or buffer. Oxygen may be produced by reaction between a peroxide and a catalyst such as catalase, optionally in the presence of a buffer. For convenience hereinafter, the invention will be described with reference to chlorine dioxide as the sterilising agent.

Suitable foam promoters will be well icnown to those, skilled in the art. Non-limiting examples include: sodium lauretli
sulphate, ammonium lauryl sulphate, cocamide DBA, cocamidopropyl betaine, sodium lauryl sarcosinate, cocamidopropylamine oxide, monoethanolamine lauryl sulphate, cocamidopropyl hydr-oxysultaine, cocoyl sarcosinate. -Ani.onic, cationic, non-ionic., and amphoteric surfactants may be - "-••
emplo}7ed depending on the chemistry of the reagents. The
foam -promoters are 'Selected to provide a stable foam
structure. The foam promoter may -comprise from about 0.1 to
50% by weight of the first part, notably from about 1 to 10%,
preferably -from about 3-to 6-%.-- ' - "

Suitable foam stabilizers well known to those skilled in the art may also be used, in proportions similar to those for the foam-promoters. Non-limiting examples include: alkanolamides, for example monoethanolamides and
diethanolamides, amine oxides, betaines, protein hydrolysates and cellulose derivatives such as carboxymethylcellulose.
In a preferred embodiment, a humect ant is included in at least one of the first and second parts. Humectants serve to 30 reduce the rate of evaporation of components and improve product feel if direct skin contact is involved. We have found that the use of a humectant reduces the volatility of chlorine dioxide, which reduces the odour of chlorine dioxide

and prolongs "he life of the activated mixture. Won-limit ing examples of suitable humectants include sodium lactate and polyols, for example glycerine, sorbitol, propylene glycol, diethylene glycol and ethylene glycol. The huiuectant may be 5 present in any desired amount, particularly from about 0.1 to 50% by weight, notably from about 0.5 to 10-%, preferably from about 1 to 3%. •
Where one of the reagents is basic or oxidising, for example sodium chlorite, it is particularly preferred that this
reagent is provided in the trigger dispenser rather than in the wipe, because such reagents may react with the fabric over time. Preferably the optional humectant is included in the first part, with the sodium chlorite or other first 15 reagent.
The first and/or second part may further include a biocide to ensure that, in the event of poor mixing of the parts, a biocidal effect is still present. The first and/or second 20 part may also include a preservative.
Equal weights of the first part and the second part may provide, when nixed, a sterilising composition having a pH of from 1.0 to 10.5, but it is preferred that the composition 25 has a pH of from 4.5 to 6.5 as this may result in a more stable compound.
A plurality of fabric members may be provided in a single resealable container, for example a canister with a lid, or a 30 resealable sachet. In a preferred embodiment, each fabric member is provided in its own sachet which may be factory-sealed and disposed of after use. In a particularly preferred embodiment, each sealed sachet contains a single

fabric wipe anc carries a removable adhesive label on its outer surface, the label containing informatiorj about the provenance of the wipe, for example its lot or batch number, its date of manufacture, or its expiry date. The label may 5 be affixed to E record sheet and used as part of an audit trail tc pro\Tide a record that an item of equipment has been properly decontaminated and the date on which this was done. In one embodiment the label adhesive and the record sheet are selected so that, though the label is releasably adhered to
the sachet, it will become permanently adhered to the record sheet and cannot be removed intact. This arrangement helps provide a permanent validation record of the decontamination process. The record sheet may be provided in any convenient form, for example as a single sheet, as part of a loose^i&arf
binder, or in an audit trail book.
It will be understood that the sterilant system may optionally be provided as a stand-alone sterilant system, for use without the pre-clean wipe or the rinse wipe, or for use 20 as a replacement component in the decontaminant system.
Rinse Wipe
To maintain sterility of the wipes it is preferred that each 25 fabric member is provided in its own sachet which is factory-sealed and disposed of after use. The sachets may be gamma-irradiated before or after sealing to ensure sterility.
In addition to water (preferably deionised water) , optional 30 components may comprise an antioxidant to neutralise oxidant in the sterilant system, a sequestering agent to sequester metal salts and improve cleaning, and a lubricant to provide visual enhancement, or "shine' to a decontaminated item such

as an entioscope. A preservative may optionally be included, to eliminate roxic residues and enhance product stability prior to gamma-irradiation.
5 Other aspects and benefits of the invention will appear in the following specification, drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS
The invent: ion will now be further described, by way of example, with reference to the following drawings in which:

Figures 1 and 3 show views of alternative embodiments of pump dispensers for use in a decontamination system in accordance with embodiments of the present invention;
Figures 2 and -4 are perspective views of a canister of
sterilising wipes for use in a decontamination system in accordance with embodiments of the present invention;
Figure 5 shows a decontamination system in accordance.
with another embodiment of the invention-; .
Figures 6 to 6 illustrate sachets from the system of Figure 5; and
Figure 9 shows a record sheet for use with the
decontamination system of Figure 5 in accordance with a further embodiment of the invention.
DETAILED DESCRIPTION
The pump dispenser 2 shown in Figure 1 is a trigger sprayer of a construction well known per se. The dispenser 2 comprises a body 24 connected to a sprayer head 4 by an internally screw-threaded connector ring 14. A spray nozzle
10 in the head is connected to an aqueous liquid 12 by means of a dip tube 6. A user dispenses the liquid 12 through the nozzle 10 by operation of a trigger 8. Rotation of the nozzle allows the user to dispense the fluid as either a

spray of fine droplets or as a foam.
In the present example, the liquid 12 (first part) comprises 0.75% of a first reagent (sodium chlorite), 3.0% foam 5 promoter (Cocamidopropyl Betaine). The remainder is
deionised water. In this specification, all parts are by weight unless otherwise indicated. Operation of the trigger 8 dispenses the first part 12 as a foam.
An alternative design of pump dispenser 2 is illustrated in Figure 3. The trigger B is formed integrally with the nozzle 10. Depressing the trigger 8 dispenses a portion of the fluid contents as a foam (referred to as the "Activator Foam' because it activates the sterilising powers of a sterilising
wipe) . A protective cap 26 is provided to cover the nozzle 10 and trigger 8 when not in use.
Turning now to :Figures 2 and 4, a scalable container 20 is also of a construction well known per se. The container 20
is a hollow cylinder fitted with a cap 22. The container 20 contains a roll of interleaved fabric sheets (or ^sterilising wipes') 18. In this example, the fabric sheets 18 are to be used as sterilising wipes, but it will be understood that the sheets 18 could also be used for other applications such as
biocidal wound-dressings.
The cap 22 has a central opening through which a tip of the central wipe 18 is disposed. By pulling the central wipe 18, a user may remove this wipe from the container, leaving the 30 next wipe in its place. A stopper 16 is provided on the cap 22 for releasably sealing the container 20.
In this example, the wipes 18 are impregnated with an aqueous

acid solution (second part). In t.his example, the acid solution comprises 0.5% citric acid, 0.05% sorbic acid, 0.05% boric acic. The solution also comprises 0.35% of a buffer (trisodium phosphate). The solution also comprises 0.25% 5 tr is odium citrate, 1.0% glycerine, 0.1% beuzotriazoie, 0.1% sodium molybdate and 0.3% sodium nitrate. The remainder is deionised water.
The pump dispenser 2 and container 20 together comprise the 10 sterilant system. To activate a sterilising wipe, a user removes the wipe IB from the container 20, and applies a portion of foam from the dispenser 2 to the wipe 18. To facilitate mixing of the reagents in the foam and the wipe., the user may fold the wipe in half and crush or rub the...*-3^. 15 folded wipe before opening it our. Preferably, one of the components is provided -with -a p-K—sen-s-iti-v-e indicator-'w-hich
changes colour or becomes coloured when adequate mixing has
%
occurred, thereby indicating that sufficient ClOs has been
generated in-the 'wipe. ._^_. .....^-

Once the sterilising wipe has been activated, it may be used for a number of applications, including wiping surfaces and sterilising medical equipment such as endoscopes.
The sterilant system illustrated in Figures 1-4 may be
accompanied by a plurality of pre-clean wipes and a plurality of rinse wipes for treatment of an item to be de-contaminated respectively before and after treatment with a sterilising wipe. Each wipe may be made from the same fabric and may
have the same dimensions. All of the wipes may be identical except for the fluid with which they are impregnated or soaked.

In the preferred embodiment illustrated in Figures 5-8, each sterilising wipe is provided in its own sealed container 20, in this example a sachet. The disinfectant system comprises £ box 32 of pre-clean wipes in sachets 30, a box 28 of 5 sterilising wipes in sachets 20, and a box 34 of rinse wipes in sachets 40. Each sachet 20, 30, 40 is factory-sealed and may be disposed of after the wipe has been removed. The foam pump dispenser 2 is also provided in the box 28 of sterilising wipe sachets 20

Each sachet 20, 30, 40 is provided with a label 48 on the front, identifying what the relevant wipe is for. A label 50 on the back gives information about how the wipe is to be used and other product details.
In this example, the pre-clean wipes contain the fluid formulation set forth in Table 1.

Table Remove

The trisodium citrate functions as a buffer; sodium benzoate functions as c preservative and corrosion inhibitor; monopropyiene glycol functions as a humectanr and soiubiliser; the enzymes promote digestion and solubiiizing 5 of organic deposits.
The fluid formulation for the rinse wipes is given in Table

Table Remove
10
RINSE WIPE FORMULATION TABLE 2
Sodium thiosulphate is -an antioxidant which helps to remove 15 traces of C102 from an item that has been sterilised. EDTA sodium salt is a seguestrant for removing dissolved metal salts and improving cleaning. The silicone emulsion functions as a lubricant to help 'shine' an item such as an endoscope and provide visual enhancement. The preservative 20 is added before the rinse wipes are gamma-irradiated, to help, reduce or eliminate toxic residue and enhance product stability prior to irradiation.
To decontaminate an item (in this example an endoscope), a 25 user first opens a pre-clean wipe sachet 30 and takes out the pre-clean wipe. This wipe is used to remove soil and debris from the surface of the endoscope, in accordance with

instructions on the label 50 of the sachet 30. After pre-cleaning, the pre-clean wipe is disposed of, and the user activates a sterilising wipe 16 by removing it from its sachet 20 and applying a metered dose of foam from the 5 dispenser 2 (in this example, two measures of foam activator are applied in. accordance with instructions on the label 50 on the back of the sachet 20) . After manipulating the wipe 18 to ensure mixing of the activator foam and the fluid in the wipe 18, the user waits about 15 seconds and then wipes 10 the surface of the endoscope for about 30 seconds. Finally, a rinse wipe sachet 40 is opened and a rinse wipe is used to wipe down the surface of the endoscope. The endoscope is now decontaminated and ready for use.
Referring now to Figure B, a record sheet 36 is illustrated for use in prox*iding a quality audit trail for an item of equipment decontaminated with an embodiment of the system of the present invention. The record sheet 36 may be loose or it may be bound in a book or file. The record sheet carries
boxes or other defined locations for recordal of information relating to the: decontamination of the item. In the present example spaces are defined for recording the type of device .to be decontaminated, its reference number, its method of decontamination, and other details including the ID number of
the patient on which the device has most recently been used, the date and time of decontamination, and the name and signature of the responsible person. The record sheet permits recording of the pre-clean wipe process, the 'sterilising process, and the rinse wipe process. It also
provides information as to the immediate destination of the decontaminated item - either for use with the patient or return to storage.

For each decontamination history of each device on the record sheet 36 there is provided a space 42 for receiving £ record book label 38 from the back of the sterilising wipe sachet 20. The user peels the sticky label 38 off the sachet and 5 affixes it in the space 42 as proof that the sterilising wipe IB has been used, and marks adjacent boxes to confirm that "he wipe IE has been properly activated by following the specified steps. If the decontaminated device is to be returned for use on the specified patient, this information
is recorded on zhe record sheet. Alternatively, i'f the
device is to be returned to storage, a second sticky label, the 'patient's notes label7 46 is peeled off the sterilising wipe sachet 20 and affixed in another box 44 on the record sheet 36. This embodiment of-the invention therefore
provides a traceability system which uses the sterilising wipe sachet "20 as evidence that the wipe -has -been used as a single-use process, uniquely identified to a specific instrument -at a specific time and date.
EXPERIMENTAL RESULTS Experiment 1
Sterising wipes 18 in accordance .with one aspect of the 25 invention were tested and compared with conventional wipes saturated with isopropanol (IPA), a general-purpose detergent, and sterile deionised water.
The test method to evaluate effectiveness of the wipes in 30 killing/removing test organisms dried onto test surfaces, involved the following steps.
1. Mark out a six inch (30.5 cm) square test area on the

test surface.
2. Inoculate the test surface with 0.5 ml of test organism
suspension.

3. Spread the inoculum over the test area using a plastic
spreader.
4. Allow the inoculum to dry (about 30 minutes) .

.
Don a pair of disposable plastic gloves.
6. Prepare a ClOj wipe in accordance with the invention,
using a prescribed mixing time.

7. Wipe the test area for the prescribed wiping time.
8. Place the wipe in 10 ml of universal neutraliser in a
Universal bottle (Test Suspension A) . Vortex stir to release
organisms.
9. Wipe the entire test area with a cotton-tipped swab
(thoroughly/10 times) .
10. Dip the swab into 10 ml of universal neutraliser in a Universal bottle after each sampling of the test area and rotate the swab against the inner wall of the bottle to release organisms (Test Suspension B) .
11. Prepare 5 serial deci-dilutions of Test Suspension A and Test Suspension B in diluent.
12. Inoculate 0.5 ml of each dilution onto a culture plate

and spread using a plastic spreader. Incubate rne plates and
ao a viable count.
13. Calculate iogaD reductions achieved from the difference 5 in the initial inoculum and the number of test organisms recovered after disinfection with a C102 wipe.
Test variables were as follows. Test Surface
A flat stainless steel instrument tray.
Test Organism -:_ -

Spores of Bacillus subtilis var.niger'UCTC 1CTC73 freshly prepared by the method of Beeby & Whitehouse.

The test surface was inoculated with 1 X 10E spores
Suspending Fluid 25 Sterile deionised water. 1 Disinfectant Concentrations
i
1. 200 ppm C102 (notional) ! 2. 300 ppm C102 (notional).
Mixing Times

15 4 30 seconds.
Wipinq Times
15 4 30 4 60 seconds
Controls
1. 1% Hospec general purpose neutral liquid detergent
(Young's Detergents)/Kimcare Medical Wipes (Kimberly-Clark).
2. Sterets Alcowipe: 70% I PA (Seton Prebtales Ltd).
3. Sterile deionised water: Kimcare Medical Wipes
(Kimberly-Clark).

Resulrs are given in Table 1.

Table Remove

TABLE 1 VC = Viable Count
Interpretation of Results
1. Washing/wiping with water, neutral detergent '(1% Bospec), or alcohol (70% 1PA) were ineffective
2. For the notional 200 ppm C1Q2 wipes the best results were obtained with a mixing time of 15 seconds and a wiping
time of 60 seconds.
3. For the notional 3.0"0 ppm CIDa wipes the "best results, ~
were obtained with a mixing time of 30 seconds and a wiping
time of 60 seconds.
4. Results for 200 ppm C102 (notional) were surprisingly
better than results for 300 ppm (notional) , except for mixing
times of 30 seconds combined with wiping times of -at least 30 seconds.
5. A wiping time of 60 seconds achieved better results than
a wiping time of 30 seconds, which in turn achieved better
results than a wiping time of 15 seconds.
6. Both C102 concentrations achieved good results after a wiping time of 60 seconds. The test surface was inoculated with 1 x 10s spores. After using the C102 wipes, surface 30 counts were reduced to 10 and 29 (200 ppm C102) and to 160 and 20 (300 ppin C102) .

7. A wipe containing 200 or 300 ppm may be useful, as may mixing times of 15 or 30 seconds (or, clearly, any intermediate times). However, it is preferred that wiping rimes longer than 15 seconds are employed.

These results were obtained using bacterial spores. It is to be expected that a vegetative bacterium such as MRSA will be much more sensitive, so that lower ClOj concentrations and/or shorter mixing or wiping times may be effective against such bacteria.

Further experiments (2-4) were carried out using 41 gsm spunlace sheets comprised of 50.5% wood pulp and 49.5% PET.
The sheets' dimensions were 160 mm x 180 mm x 0.36 mm. In each experiment the wipes each contained 3 ml of Solution A (formulated as set forth below) , made by treating a canister of 50 wipes with 150 ml of Solution A. Each wipe was activated with 1.5 ml of Solution B (formulated as set forth
below) from a foam dispenser.
Solution A (Wipe)
Formulation:

Table Remove

Solution B (Foam)
Formulation:

Table Remove
Experiment 2
A study was carried out to compare the effectiveness of (a) C102 wipes in accordance with the invention (b) a 70% IPA wipe (c) a neutral detergent wipe and (d) a water wipe in removing and/or killing (1) B. subtilis spores, and (2) P.

aeruginosa cells dried onto the insertion tube of E flexible endoscope .
Wipes were prepared fresh as required by squirting foam onto
a wipe and then scrunching the wipe with the fingers to mix
the reagents to form
EXPERIMENT 2
Test organisms
B. subtilis NCTC 10073 spores
A suspension containing approximately 108 spores/ ml was prepared by the method of Beeby & Whitehouse. A 1 in 10
dilution in sterile distilled water was prepared to produce a suspension containing approximately 107 spores/ ml.
P. aeruginose biCTC 6749
A culture containing approximately 10s cells/ ml was prepared by inoculating a tube of nutrient broth and incubating for 18 h at 37° C.
Insertion tube used in Experiment 2

The insertion tube was 1 metre long, in good condition, with clear markings. The test site used was the 10 cm section between the 30 and 40 markings.
Test Method
1. Immerse a cotton-tipped swab into a suspension of spores or vegetative cells.

2. Inoculate entire surface area of test sire with the suspension. Repeat several times. Regarding £. .subtilis spores, assume that (1) the volume of inoculum = 0.1 ml, and [2] the mortality rate on drying out is sero. Hence the 5 viable count of 'the inoculum - approximately 10e spores.
Regarding P* aeruginosa .cells, assume that (1) the volume of inoculum = C.I ml, and (2) the mortality rate on drying out is 1 log. Hence the viable count of the inoculum = approximately 10e cells.
3. Place inoculated insertion tube across the top of an
empty discard jar with the 10 cm test site resting over the
centre of the jar. Allow inoculum to dry -.out (approximately
30 minutes).
4. Dor. pair ..of disposable plastic gloves. • Jaorr
5. Prepare a Wipe: C1Q2 (scrunch time = 15 sec) , IPA,
Hospec or water. • ;
6. Wipe test site for the prescribed wipe time (30 sec) as follows: Wrap wipe loosely around .the insertion tube and then wipe up and down the test site repeatedly.
7. Place the wip.e in 20 ml of universal neutraliser in. .a Universal bottle. Vortex stir to release recovered spores/ cells (Test Suspension A).
8. Swab entire test site with a cotton-tipped swab. Dip swab into 10 ml of universal neutraliser in a Universal
bottle and rotate swab against the inner wall of the bottle to release recovered spores/ cells. Repeat 10 times then break off cotton-tip of swab and leave in the neutraliser. Vortex stir to release recovered spores/ cells (Test Suspension B).
9. Prepare 5 serial deci-dilutions of Test Suspension A and Test Suspension B in diluent.

10. inoculate 0.5 ml of each dilution onto a culture plate
and spread using a plastic spreader. Incubate plates. Viable
count.
11. Calculate Iog10 reductions achieved from the difference
in the number of spores or cells inoculated onto the test
site (approximately 106) and the number recovered after
cleaning and/or disinfection.
Wipes used In Experiment 2

1. C102 Wipe (scrunch time = 15 seconds).
2. 70% IPA wipe: Azowipe (Vernon Carus).
3. Hospec wipe: Kimberley Clark Medical Wipe immersed in 1%
Hospec and then squeezed to remove excess solution.
4. Water wipe: Kimberley Clark Medical Wipe immersed in
sterile water and then squeezed to remove excess water.

EXPERIMENT 2 - EZSDLTS

Table 2

Table Remove
Table 3
a Viable count in Table 1 x 20 (0.5 ml of 10 ml neutraliser plated out) .
2 Viable count in Table 1 x 40 (0-5 ml of .20 -.ml neutraliser plated out) .
EXPERIMENT 2 - CONCLUSIONS
1. C102 wipes were completely effective against both B.
subtilis spores and P. aeruginosa cells. No spores or
cells were recovered in duplicate experiments. 15 2. IPA wipes exhibited good activity against P. aeruginosa
cells but did not eliminate all of the test cells - 40 viable
cells were recovered from the test site on the insertion
tube.
3. IPA wipes were ineffective against B. subtilis spores. 20 IPA proved less effective than 1% Hospec or water which may

be attributable to the coagulant properties of alcohol ('fixing spores on the test site) .
. Wipes saturated with 1% Hospec were ineffective against either B. suJbtilis spores or P. aeruginosa cells. 5 5. Wipes saturated with water were ineffective against either B. snbtilis spores or P. aeruginosa cells.
Experiment 3
EVALUATION OF SEC EFFECTIVENESS OF C1O2 WIPES IN KILLING/ REMOVING METEICILLIN RESISTANT STAPESLOCOCCTTS ADREUS (MRSA) DRIED ONTO A STAINLESS STEEL TEST SURFACE
Test Method

The following test method was used to evaluate the effectiveness of ClOs Wipes in killing/ removing test-organisms dried onto test surfaces. The test method involves the following steps:

1. Mark out an 18 inch (457.2 mm) square on the test
surface.
2. Inoculate test surface with 4.5 ml of test organism
suspension.
3. Spread inoculum over 18 inch (457.2 mm) square test area using a plastic spreader.
4. Allow inoculum to dry (30-60 minutes).
5. Don pair of disposable plastic gloves.
6. Prepare a C1C>2 Wipe using the prescribed scrunch time
(15 seconds) .
7. Wipe test area for the prescribed wipe time (30
seconds).

8. Place the CIO; Wipe in 20 ml of universal neutraliser in
a universal bottle. Vortex stir to release organisms. (Test
Suspension A).
B. Swab entire rest area with a cotton-tipped swab. Dip swab into 10 ml of universal neutraliser in a universal
bottle and rotate cotton-tip againsr the inner .wall of the
bottle to release organisms. Repeat 10 times. Finally, snap
off cotton-tip into the neutraliser. Vortex stir .to release
organisms. (Test Suspension B). 10 10. Prepare 5 serial deci-dilutions of Test Suspension -A and
Test Suspension B in diluent.
11. Inoculate 0.5 ml of each dilution onto a culture plate
and spread using a plastic spreader. Incubate plates. Viable
count. 15 12. Calculate logio reductions achieved from the difference
in the initial inoculum and the number of test organisms ""
recovered after cleaning/ disinfection with a C1O2 Wipe.
13. Repeat above using control wipes (70% IPA, 1% Hospec '&
sterile -water) .
Variables selected, in Experiment 3
Test surface
A flat stainless steel laboratory bench. Test organism
Methicillin Resistant Staphylococcus aureus (MRSA) : a 30 clinical isolate from the Royal Preston Hospital.

Inoculum
The rest surface was inoculated with >10S bacterial cells: 4.5 ml of an overnight culture in Nutrient Broth. 5
Suspending fluid Nutrient Broth 10 Scrunch time 15 seconds
Wipe time

30 seconds
Controls
1. 70% IPA wipe: Azowipe (Vernon Carus).
2. 1% Hospec general purpose neutral liquid detergent (Young's Detergents) / Kimcare Medical Wipe (Kimberly-Clark). The wipe was immersed in 1% Hospec and then squeezed with the fingers to remove excess fluid.
3. Sterile deionised water / Kimcare Medical Wipe
(Kimberly-Clark) . The wipe was immersed in water and then squeezed with the fingers to remove excess fluid.

Results

Table Remove
Table 4

Table Remove
Table 5
a Viable Count in Table 1 x 20 (0.5 ml of 10 ml neutraliser plated out) .
2 Viable Count in Table 1 x 40 (0.5 ml of 20 ml neutraliser plated out) .

Interpretation of results
1. Wiping with a CIO; Wipe for 30 seconds was completely
effective. No test organisms were recovered from either the
test surface or the wipes in duplicate experiments.
2. Wiping the test surface with a 70% IPA wipe (Azowipe)
for 30 seconds was ineffective. This could be due to:
(a) an exposure time of 30 seconds was not long enough to
kill the MRSA
(b) the IPA evaporated off the test surface before the
minimum exposure time required to kill the MRSA
(c) the volume of IPA on the wipe was insufficient to
deal with the >10S MRSA dried onto the 18 inch test surface
(d) a combination of the above.
3. Only 360 test organisms were recovered from the
Azowipe. This could be due to :
(a) entrapment of test organisms in the fibres
(b) incomplete/ slow neutralisation of the residual IPA on the wipe by the
neutraliser (c) a combination of the above
4. Wipes saturated-with either 1% Hospec or sterile water were ineffective.
Experiment 4
This experiment was carried out to evaluate the effectiveness of C102 Wipes in killing/ removing spores of Bacillus subtilis var. niger NCTC 10073 dried out for 24 h at room temperature on a stainless steel test surface.

Test Method
1. Mark out a 12 inch (304.8 ram) square on the zesr
surface.
2 . Inoculare rest surface with 1. 0 ml of aqueous spore suspension.
2. Spread inoculum over 12 inch (304. B mm) square test area
using a plastic spreader.
4. Allow inoculum, to dry out naturally at room temperature for 24 h.
5. Don pair of disposable plastic gloves. 6.. 'Prepare a C102 Wipe using-the prescribed .scrunch time. (15 seconds.).. • " '•• • ... - . j^,.
1. Wipe test area for the prescribed wipe time (30 seconds) .
8. Place the C1C>2 Wipe in 20 ml of universal neutraliser in
a universal bottle. Vortex stir to release organisms. (Test
Suspension A). • • ~ "~
B, Swab entire test area with a cotton-tipped swab. Dip swab into 10 ml of universal neutraliser in a universal bottle and rotate cotton-tip against the inner wall of the bottle to release organisms. Repeat 10 times. Finally, snap off cotton-tip into the neutraliser. Vortex stir to release
organisms. .(Test Suspension B) .
10. Prepare 5 serial deci-dilutions of Test Suspension A and
Test Suspension B in diluent. :
11. Inoculate 0.5 ml of each dilution onto a culture plate
and spread using a plastic spreader.
12. Repeat above using a control wipe (a Medical Wipe saturated with sterile water). 13. Incubate plates. Viable count.

14. Calculate logic reductions achieved using the C102 Wipe from the difference in viable count obtained using the C.102 Wipe and the control wipe.
Variables selected in Experiment 4 Test surface
A flat stainless steel instrument tray.
Test organism
Bacillus subtilis var. niger NCTC 10073. A spore suspension was prepared by the method of Beeby & Whitehouse. 15
Inoculum
The test surface was inoculated with (a) 106 spores, and (b) 108 spores. 20
Suspending fluid
Deionised water. Drying time
The inoculated instrument tray was allowed to dry out naturally at room temperature for 24 h in a dark cupboard.

Scrunch time
15 seconds.

Wipe rime
30 seconds
Conrroi
1. Sterile deionised water / Kimcare Medical Wipe (Kimberly-Clark) . The wipe was immersed in water and then 10 squeezed with the fingers to remove excess fluid.
Results

Table Remove

Table Remove
Table 7
1 Viable Count in Table 1 x 20 (0.5 ml of 10 ml neutraliser
plated out).
2 Viable Count in Table 1 x 40 (0.5 ml of 20 ml neutraliser
plated out).

Interpretation of results
1. Spores dried out for 24 h at room temperature on a
stainless steel test surface were not easy to dislodge using
a Medical Wipe saturated with deionised water. With the 106
inoculum the recovery was 4.0-8.4 x 103 spores leaving 2-3
logio spores on the surface (assuming no mortality). With the
106 inoculum the recovery was 1.3 -7.6 x 106 spores leaving 1-
2 logic spores on the surface.
2. C102 Wipes were effective in killing/ removing spores
dried out for 24 h at room temperature on the stainless steel
test surface. With the 106 inoculum, no spores were recovered
from either the surface or wipe which represents a 3-4 Iog10
reduction on both the surface and wipe. With the 108

inoculum, a 2-2 logic, reduction of spores was achieved on the surface anc a 3-4 logic reduction on the wipe.
Thus., the invention provides e decontamination system which 5 can be prepared in sitv and which provides bactericidal, fungicidal, virucidal, and sporicidal fabrics. The system is particularly useful for sterilising wipes and for the dressing of wounds and ulcers.
It is appreciated that certain features of the invention which are, for clarit}-7., described in the -.context of separate embodiments., may also be provided in combination in a single embodiment. Conversely/ various_ features of the. invention which are, for brevity, described -in .the context of -a single
embodiment, .may. also 'be provided separately..,-— or-, in -any suitable combicatipn. It is to be rec^ognised that _various alterations, modifications, arid/or additions may be introduced into the constructions and arrangements of parts described above without departing from the ambit of the
present invention. As used herein, the indefinite articles ^ar and 'an' connote ^one or more' unless the context requires otherwise.
The disclosures in United Kingdom patent application No.
0410204.2, from which this application claims priority, and
in the abstract accompanying this application are
incorporated herein by reference.

CLAIMS
1. A decontamination system suitable-for decontaminating items of medical equipment such as endoscopes, the system 5 comprising:
(I) a plurality of pre-clean wipes comprising moist
fabric members for wiping an item to be decontaminated;
(II) a two-part sterilant system comprising:
(a) a first part comprising a first reagent in a
carrier medium; and
(b) a second part which is miscible with the first part
and which comprises a second reagent in a carrier medium;
•wherein the first reagent and the second reagent will react when mixed to provide a sterilising composition;
the first part being contained in a dispenser whereby it may be dispensed as a fluid, and the second part being absorbed or impregnated in a plurality of sterilising wipes each of which comprises a fabric member in a sealed container; and
(III) a plurality of rinse wipes, each rinse wipe
comprising a moist, sterile, fabric member in its own sealed container.
2. A decontamination system according to claim 1, further
comprising a record sheet for recording information
concerning decontamination of an item of equipment.
3. A decontamination system according to claim 2, wherein
each sterilising wipe is provided in its own sealed container
and each of said containers carries on an outer surface a
removable adhesive label which provides information about the contents of the container including at least one of: the lot or batch number; the date of manufacture; a use-by or expiry

date; anc
wherein said record sheet includes a space for receiving said label.
4. A decontamination system according tc claim 3, wherein said record .sheet comprises a logbook which carries predefined spaces for receiving adhesive labels from each container for said sterilising wipes.
5. A decontamination system according to any preceding
claim., wherein said first part includes a foam promoter and is contained in a trigger-operated foam dispenser.
6. A -decontamination -system according TO any -preceding5***
claim, wherein at least one of said first part and said
second part includes an indicator reagent that changes colour when the parts are mixed together.
7. A decontamination system according to claim • "67"' wherein
said first part and .said second part have a different pH and
wherein the indicator reagent changes colour in response to a change in pH when the parts are mixed.
8. A decontamination system according to any preceding
claim, wherein one of said first part and said second part
comprises a solution containing sodium chlorite or sodium chlorate and the other comprises an acidic solution.
9. A decontamination system according to claim 8, wherein
the acidic solution comprises a solution of citric acid,
sorbic acid and boric acid.
10. A decontamination system according to any preceding

claim, wherein said first part further comprises from O.I to 50% w/w of at least one foam promoter.
11. A decontamination system according to any preceding
claim, wherein one of said first part and said second part further comprises from 0.1 to 50% w/w of a humectant.
12. A decontamination system according to any preceding
claim, wherein when equal weights of said first part and the
second part are mixed they provide a sterilising composition having a pH of from 4.5 to 6.5.
13. A decontamination system according to claim 8, wherein
said first part comprises said solution of sodium chlorite or
sodium chlorate.
14. A decontamination system according to any preceding
claim, wherein said pre-clean wipes contain at least one
surfactant.

15. A decontamination system according to any preceding
claim, wherein said pre-clean wipes contain at least one
enzyme for digesting or solubilizing organic deposits.
16. A decontamination system according to any preceding claim, wherein said rinse wipes include an agent for neutralising an active ingredient of the sterilant system.
17. A decontamination system according to any of claims 1-30 15, wherein said sterilant system will produce an oxidising agent when the first and second parts are mixed, and wherein said rinse wipes contain an antioxidant to at least partly neutralise or reduce said oxidising agent.

IB. A decontamination system according to claim 17, wherein said oxidising agent is CIO: and said antioxidar.t is sodium thiosnlphate.

19. A decontamination system according to any preceding
claim, wherein said rinse wipes further contain at least one
component selected from: a sequestering agent,- a lubricant,
and a preservative.

20. A decontamination S3^steiri according to any preceding
claim, wherein each pre-clean wipe, each sterilising wipe,
and each rinse wipe is provided in its own sealed sachet.

Documents:

6254-delnp-2006-Abstract-(05-06-2014).pdf

6254-delnp-2006-abstract.pdf

6254-delnp-2006-Assignment-(05-06-2014).pdf

6254-delnp-2006-Claims-(05-06-2014).pdf

6254-delnp-2006-claims.pdf

6254-delnp-2006-Correspondence Others-(05-06-2014).pdf

6254-delnp-2006-Correspondence Others-(10-01-2014).pdf

6254-delnp-2006-Correspondence Others-(18-10-2013).pdf

6254-DELNP-2006-Correspondence-Others-(19-10-2010).pdf

6254-delnp-2006-correspondence-others.pdf

6254-delnp-2006-description (complete).pdf

6254-delnp-2006-drawings.pdf

6254-delnp-2006-form-1.pdf

6254-delnp-2006-form-2.pdf

6254-delnp-2006-Form-3-(10-01-2014).pdf

6254-DELNP-2006-Form-3-(19-10-2010).pdf

6254-delnp-2006-form-3.pdf

6254-delnp-2006-form-5.pdf

6254-delnp-2006-gpa.pdf

6254-delnp-2006-pct-237.pdf

6254-delnp-2006-pct-304.pdf

6254-delnp-2006-pct-306.pdf

6254-delnp-2006-pct-search report.pdf

6254-delnp-2006-Petition-137-(05-06-2014).pdf

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Patent Number

263481

Indian Patent Application Number

6254/DELNP/2006

PG Journal Number

44/2014

Publication Date

31-Oct-2014

Grant Date

30-Oct-2014

Date of Filing

25-Oct-2006

Name of Patentee

TRISTEL PLC

Applicant Address

UNIT 4C, LYNX BUSINESS PARK, FORDHAM ROAD, SNAILWELL, NEWMARKET CB8 7NY, UK

Inventors:

#	Inventor's Name	Inventor's Address
1	SWINNEY, PAUL	UNIT 4C, LYNX BUSINESS PARK, FORDHAM ROAD, SNAILWELL, NEWMARKET CB8 7NY, UK
2	GREEN, BRUCE PHILIP	WINWICK HALL, NORTHAMPTON NN6 7BP. UK

PCT International Classification Number

A61B1/12

PCT International Application Number

PCT/GB2004/003227

PCT International Filing date

2004-07-26

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	0410204.2	2004-05-07	U.K.