GB2520287A

GB2520287A - Apparatus and method to verify Thermal Disinfection in the field of appliances such as laundry washing machines and automatic dishwashing machines

Info

Publication number: GB2520287A
Application number: GB1320106.6A
Authority: GB
Inventors: Andrew Leslie Wade
Original assignee: PHS LAUNDRYSERV
Current assignee: PHS LAUNDRYSERV
Priority date: 2013-11-14
Filing date: 2013-11-14
Publication date: 2015-05-20
Also published as: GB201320106D0

Abstract

The apparatus is a device which may be placed inside a washing machine to verify that thermal disinfection has taken place by periodically sampling the temperature during a washing cycle. The results are automatically compared with local, regional, national or international standards for thermal disinfection. At the end of the washing cycle an indication is given that either thermal disinfection has taken place or that thermal disinfection has not taken place. The measurement, comparison and indication are independent of the temperature and time measurement parts of the washing machine and also independent of external human or mechanical or electronic computation and analysis. The device may be used in appliances such as laundry washing machines, automatic dishwashing machines or other washing machines.

Description

Apparatus and method to verify Thermal Disinfection in the field of domestic or institutional appliances such as laundry washing machines, automatic dish-washing machines, and other washing machines.

Field of the Invention

[0001] The present invention relates to apparatus, methods and systems for verifying that thermal disinfection has taken place in cleaning or washing a soiled item or items. In particular it relates to apparatus, methods and systems applicable in the field of domestic or institutional appliances such as laundry washing machines, automatic dish-washing machines, and other washing machines, and which enable improved verification and monitoring of the thermal disinfection of soiled items over time.

Background of the Invention

[0002] In recent years there has been growing requirement for the monitoring and verification of the thermal disinfection process when washing laundry and other soiled items. This is particularly but not exclusively in institutions such as hospitals, care homes and other health care settings.

[0003] Thermal disinfection is defined in various legislation, procedures and guidelines according to jurisdiction in terms of a minimum temperature and a minimum time that that temperature must be exceeded by.

[0004] In some legislation, procedures and guidelines there are several acceptable combinations of minimum temperature and minimum time; where a short time at a high temperature is deemed equivalent in thermal disinfection to a longer time at lower temperature. For example in the UK Department of Health Choice Framework for local Policy and Procedures 01- 04 -Decontamination of linen for health and social care: Engineering, equipment and validation. The guideline states:- "The temperature should be continuously maintained at or above 65°C for not less than ten minutes or 71°C fe not less than three minutes." Apparatus and method to verify Thermal Disinfection in the field of domestic or institutional appliances such as laundry washing machines, automatic dish-washing machines, and other washing machines.

[0005] Some legislation, procedures and guidelines have one temperature time combination others may have two or more. Currently the washing machine manufacturers' specifications are relied upon to ensure thermal disinfection, this is backed up in some cases by periodic calibration checks using thermometers where the data is manually analysed and interpreted.

[0006] An example of a guideline is the UK Department of Health Choice Framework for local Policy and Procedures 01- 04 -Decontamination of linen for health and social care: Engineering, equipment and validation. This is an example of a guideline as the apparatus may be manufactured programmed to suit other legislation, procedures and guidelines that may be enforced in other areas. This guideline states that "Thermal disinfection of the load should be deemed to have been achieved if,, when tested as part of BS EN 14065 procedures or in accordance with this CFPP, the specified minimum temperature for the specified minimum (holding) time is achieved on all items that need to be disinfected.

The temperature should be continuously maintained at or above 65°C for not less than ten minutes or 71°C fe not less than three minutes." [0007] Other minimum temperatures and minimum (holding) times may be accommodated in the apparatus and variants produced to suit other legislation, procedures and guidelines.

[0008] For infection control in catering, health care and other settings thermal disinfection is relied on in the washing of soiled items in the field of domestic or institutional appliances such as laundry washing machines, automatic dish-washing machines, and other washing machines.

[0009] It clearly would be desirable to monitor and verify the efficacy of current washing machines and systems, so as to ensure that adequate thermal disinfection performance is delivered.

[0010] It would also be desirable to be able to perform this monitoring and verification more frequently, even to the level of verifying each wash cycle. Current methods of measurement, data capture and analysis which rely on skilled operators, technicians or engineers make frequent verification at this level impractical.

[0011] It is an object of the present invention to provide apparatus, methods and systems applicable in the field of domestic or institutional appliances such as laundry washing machines, automatic dish-washing machines, and other washing machines, which enable improved verification and monitoring of thermal disinfection when cleaning a soiled item or items.

[0012] It is a further object of the invention to provide apparatus, methods and systems for verification and monitoring of thermal disinfection enabling more efficient usage of human resources.

[0013] It is a further object of the invention to provide apparatus, methods and systems for verification and monitoring of thermal disinfection against specific procedures and guidelines appropriate to the country or jurisdiction.

[0014] It is a further object of the invention to provide apparatus, methods and systems for verification and monitoring of thermal disinfection to be carried out frequently and by unskilled operatives.

Statement of invention.

[0015] The present invention is a device which may be placed inside a washing machine to verify that thermal disinfection has taken place by periodically sampling the temperature during a washing cycle, automatically comparing the results with; local, regional, national or international standards for thermal disinfection; giving at the end of the washing cycle an indication that either thermal disinfection has taken place or that thermal disinfection has not taken place; this measurement, comparison and indication being independent of the temperature and time measurement parts of the washing machine and also independent of external human or mechanical or electronic computation and analysis.

The present invention enables unskilled, non-technical staff engaged in washing activities to verify that thermal disinfection of washed items has occurred. The verification is presented as a simple pass I fail, that is, yes disinfection has been verified / no disinfection has not been verified.

The present invention compares the temperature over time during the washing cycle directly with specific temperature and time guidelines for thermal disinfection appropriate to the country or jurisdiction where it is used. For manually recorded verification of thermal disinfection no external equipment, calculation or specialist knowledge is required.

Summary of the Invention

[0016] The first embodiment of the present invention comprises an apparatus for monitoring and verifying that thermal disinfection has taken place in cleaning or washing a soiled item or items.

[0017] In particular the first embodiment of the present invention comprises an apparatus applicable in the field of domestic or institutional appliances such as laundry washing machines, automatic dish-washing machines, and other washing machines.

[0018] At the start of the washing cycle or process the apparatus described as the first embodiment of the present invention will be activated by the manual operation of a switch [0032] I) and inserted into the washing appliance in contact or close proximity to the soiled items being washed. The apparatus is constructed as a sphere, rounded cylinder, cylinder or other smooth shape that will not tend to damage the soiled items being washed [Fig. 4].

[0019] During the washing cycle or process the apparatus will periodically measure and store the temperature of the water or environment that the soiled items are being washed at. At the end of the washing cycle the apparatus will compare the stored temperature and time data to the specific temperature and time guidelines appropriate to the country or jurisdiction.

[0020] After comparison to the specific temperature and time guidelines appropriate to the country or jurisdiction, the apparatus will indicate by means of an flag, indicator, lamp or display that either thermal disinfection has taken place or indicate by means of an different or easily distinguishable flag, indicator, lamp or display that thermal disinfection has not taken place.

[0021] The apparatus will indicate that adequate thermal disinfection has taken place [0019] if any or all of the temperature and time combinations set out in guidelines or legislation have been met.

[0022] The apparatus will indicate that adequate thermal disinfection has not taken place [0019] if none of the temperature and time combinations set out in guidelines or legislation have been met.

[0023] There will be country and industry specific variants of the apparatus programmed with the applicable temperature and time combinations to meet local guidelines and / or legislation.

[0024] The unskilled machine operator can visually note and record that thermal disinfection has or has not taken place without the need to manually analyse temperature data or to use IT systems, software or hardware.

[0025] Frequent verification and monitoring reduces the risk that a fault in the temperature control of the washing appliance will result in an undetected failure in thermal disinfection.

[0026] The second embodiment of the present invention is as described above as the first embodiment with the addition of parts, and programming to allow it to automatically sense the rise in temperature at the start of the washing cycle or process.

[0027] In the second embodiment of the present invention the automatic initiation of the measuring and comparison process further simplifies the task of monitoring and verifying that thermal disinfection has taken place as the operator does not need to manually activate the apparatus.

[0028] The third embodiment of the present invention is as described above as the first and second embodiments with the addition of parts, and programming to allow it to store temperature, time and date information for each washing cycle or process.

[0029] In the third embodiment of the present invention this stored data may be read or downloaded by connection to a computer, smart-phone, data storage system or other information technology equipment.

[0030] In the third embodiment of the present invention this stored data may be used as part of a quality control system to provide evidence that regular monitoring and verification has been done and that thermal disinfection has taken place.

[0031] The first embodiment of the current invention comprises the elements as shown in detailed drawing [Fig. 1] The detailed drawing shows the modified sphere variant of the apparatus, all of the features shown on this drawing apply to the other possible external shapes unless explicitly stated.

[0032] The elements shown in [Fig. 1] are; a) External waterproof case or housing, b) Dual Platinum Resistance Temperature Detectors (RTD) PT5O, PT1 00 or PT1 000 to International Standard lEG 751:1983, c) Battery to supply power. d) Means of coupling the battery to an external charger which may comprise mechanical electrical contacts or an inductive coupling or a capacitive coupling or some other means of connecting the apparatus to a battery charger, e) Electronic circuits and I or software and / or firmware to sample, store and compare the temperature and time information, f) Real time clock circuits and / or software and / or firmware such that the temperature information may be sampled regular intervals, g) Flag, indicator, lamp or display to indicate that thermal disinfection has taken place. h) Flag, indicator, lamp or display to indicate that thermal disinfection has not taken place.

i) Flag, indicator, lamp or display to indicate that an internal error has occurred. j) Mechanical, inductive, capacitive or optical switch to start the apparatus' sampling, measuring, data storage, data comparison and indication functions and allow verification of the thermal disinfection process.

[0033] The second embodiment of the current invention comprises the elements as shown in detailed drawing [Fig. 2] The detailed drawing shows the modified sphere variant of the apparatus, all of the features shown on this drawing apply to the other possible external shapes unless explicitly stated.

[0034] The elements a) to j) shown in [Fig. 2] are identical in

description to elements a) to j) in [Fig. 1].

[0035] In [Fig. 2] element k) comprises Electronic circuits and / or software and / or firmware to allow for an automatic start' function. The automatic start' function is triggered by detecting a rate of change of temperature such that the start of the washing process can be determined.

[0036] The automatic start' function further de-skills' the verification and monitoring of thermal disinfection making it more likely that it will be carried out effectively by unskilled operators.

[0037] The third embodiment of the current invention comprises the elements as shown in detailed drawing [Fig. 3] The detailed drawing shows the modified sphere variant of the apparatus, all of the features shown on this drawing apply to the other possible external shapes unless explicitly stated.

[0038] The elements a) to k) shown in [Fig. 3] are identical in

description to elements a) to k) in [Fig. 2].

[0039] In [Fig. 3] element I) comprises Electronic circuits and / or software and / or firmware and a connection method to allow the apparatus to store temperature, time and date information for each washing cycle or process.

[0040] In this third embodiment of the present invention the stored data may be read or downloaded by connection to a computer, smart-phone, data storage system or other information technology equipment.

[0041] In [Fig. 3] element m) comprises the means of coupling the apparatus to a computer, smart-phone, data storage system or other information technology equipment may comprise mechanical electrical contacts or an inductive coupling or a capacitive coupling or some other means of connecting the apparatus to a computer, smart-phone, data storage system or other information technology equipment.

[0042] In all embodiments of the present invention and any shape of the external housing of the apparatus including those shown in [FIG. 4]. There may be fixed an external shock absorbing; ring, covering or protrusion to protect the apparatus from the effects of collision with the moving parts of the washing machine.

[0043] In [Fig. 4] elements; n), o), p) comprise possible external shock absorbing; ring, covering or protrusions.