GB2434535A

GB2434535A - A sanitising chamber

Info

Publication number: GB2434535A
Application number: GB0601579A
Authority: GB
Inventors: Peter Herbert Holmes; Nigel John Brace Parker
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-01-26
Filing date: 2006-01-26
Publication date: 2007-08-01
Anticipated expiration: 2026-01-26
Also published as: GB0601579D0; GB2434535B

Abstract

A cabinet comprising a chamber, through which packaged ingredients and consumable materials pass from a low care environment to a high care environment within a food production facility. The chamber provides the packaged ingredients and consumable materials with a controlled surface sanitiser provided by ozone. A processor controlled system is installed within the chamber and provides sequencing of ozone generation and door closure secured by magnetic locks. Preferably the cabinet is made from food grade stainless steel and has a door at two opposing ends. Preferably one of the doors allows access from the low care environment and the other one of the doors allows access from the high care environment. Preferably both doors remain closed during a sanitising/sterilising ozone treatment. Advantageously microbial contamination is reduced during transfer of packaged ingredients and consumable materials.

Description

A CHAMBER EMPLOYING OZONE TO SURFACE-SANITISE PACKAGING.

PACKAGED INGREDIENTS AND PRODUCTION CONSUMABLES UNDER A

CONTROLLED TRANSIT FROM A LOW CARE TO A HIGH CARE FOOD

MANUFACTURING ENVIRONMENT

Introductton to the tnvention

1 Field of the Invention

2. This invention relates to a chamber, within which, when closed and sealed, ozone is generated and released at a predetermined level.

3. This device has been designed in the form of a stainless steel cabinet, installed to bridge the division between a low or intermediate care environment and a high care environment within food production facilities, in order to allow the surface sanitizing, by ozone, of packaged ingredients, packaging and production consumable materials being transferred from the former to the latter.

4. Description of the Related Art

5. The transfer of packaged ingredients, packaging and production consumable materials from a low-care, or an intermediate-care environment, to a high-care environment always introduces the risk of microbial contamination.

6. With unpackaged ingredients entering high-care environments, this risk can be significantly reduced by employing transition systems, which range from sanitising immersions to blanching, processes not easily made compatible with the introduction of the packaged ingredients and non-food materials described above.

7. In these cases, the risk can be reduced by adopting appropriate protocols for the manual transfer of packaging and production consumables, especially as these are generally double wrapped, with the outer wrapping acting as a protective layer to contain the relatively sanitised contents. In such cases, protocols are structured to allow the outer packaging to be opened in the low-care side of a separating wall, and then to permit removal of the contents, via a closable opening i.e., a hatch or doorway, by operatives in the high-care environment, with care being taken not to touch the outer packaging.

8. This approach is, however, not suitable for packaged ingredients, where the packaging can range from cans, plastic drums and bottles to plastic pouches, which due to their food manufacturing origin, long-term storage and subsequent handling, will generally carry significant microbial populations. In such cases, a surface sanitising treatment is required, such as immersion, fogging or UV radiation.

9 Some packaged ingredients may also be buoyant and thus be difficult to manage effectively in a sanitizing immersion system.

I

10. Once having undergone such treatments, however, the surface of the packaging will be wet and may require drying before opening, in order to avoid the possibility of water-born contamination of the contents.

11 The employment of UV radiation as a surface sanitizer within a transition system is limited in its effectiveness to directly exposed surfaces only. Those surfaces in shadow will not be sanitized and as it is not practical to orientate packaged ingredients, packaging and production consumable materials so as to achieve full exposure, the use of such a system is very limited in this application.

12.The above (ow, or intermediate care environment to a high care environment, surface sanitising, transition systems all have difficulties in ensuring effective surface sanitisation and are extremely vulnerable to unintentional, and more especially, intentional abuse by procedural avoidance.

13 The use of ozone as a sanitizing agent in a low-care, or an intermediate-care environment to a high-care environment transition system, is consistently very effective and the quality of disinfection is assured. This avoids the problems and limitations of those existing systems already described, where the quality of disinfection is compromised and their operation is open to misuse.

14. Ozone as a powerful oxidising agent is also a powerful terminal surface sanitizer, which as a gas, and unlike UV, will penetrate to all available contact surfaces of any packaged ingredients, packaging and production consumable materials introduced into the sanitising chamber.

Ozone also has a very short half life, during which it will dissociate back to oxygen, thus leaving no undesirable residues on the contact surface, nor any environmental contamination.

16 Unlike immersion, the use of ozone in a low, or intermediate care environment to a high care environment, surface sanitising, transition system can be an entirely dry operation.

17.The device compnses a cabinet fabricated throughout from food contact grade 306 stainless steel, which will be constructed to dimensions designed to meet the particular throughput requirements of individual installations.

18 To aHow hose-down' cleaning, the cabinet is constructed with welded seams and any surface mounted electrical/electronic controls or indicators are water-proof.

19.The cabinet has a sanitising chamber, which is accessible from both the low or intermediate care environment and the high care environment, by a door at each end (see Fig. 1).

20. The sanitising chamber is constructed with an inner perforated, dimple-profiled.

sheet stainless steel liner, suspended and separated from the floor, walls and ceiling to allow both the unrestricted circulation of ozone and its optmised surface contact with materials contained within.

21 Each door is fitted with vapour seals to minimise the risk of ozone escaping from the chamber into the working environment.

22. Each door is fitted with processor-controlled magnetic door locks.

23 The cabinet is fitted with an ozone generator, which, using air as a source of oxygen, is capable of generating ozone within the sanitising chamber at levels of up to 1 500mg/hr.

24.Alternatively, using a food grade oxygen supply as the source of oxygen, the ozone generator is also capable of generating ozone within the sanitising chamber at levels of up to 4500mg/hr.

25.Ozone generated within the sanitising chamber, at a level of 1500mg/H, for the appropriate cycle period, will achieve up to a log 3 reduction in the initial contaminating populations of a range of human pathogenic or food spoilage organisms including: -* E.coIi * Staph. aureus * Enterobacteriacae * Yeasts and Moulds 26 The operation of the ozone generator is controlled by a processor, which provides a limited number of pre-set cycle times.

27 Immediately post ozone generation, an extraction fan will start operating and continue doing so for a further 60 seconds after ozone generation has ceased. This is to allow the atmosphere of the sanitising chamber to be exhausted through an active-carbon filter in order to effect the removal of residual ozone before the sanitising chamber is opened.

28. In the event that mains power is removed from the cabinet, either intentionally or unintentionally, as a safety measure to prevent the doors being opened while there may be ozone within the sanitizing chamber, an actuator is fitted. This will be disengaged when power is on, the doors operating as required by the processor, but when power is removed, the actuator will manually fall into a door locking position and any closed door will remain locked until mains power is restored, allowing ozone in the atmosphere of the sanitising chamber to be safely dissociated to back to oxygen before the sanitising chamber can be opened.

29. In order to monitor the ozone concentration, the cabinet is fitted with a self-sealing port, to allow sampling of the atmosphere within the sanitising chamber 30.To increase, if required, the micro-biocidal efficiency of ozone surface sanitisation, the cabinet is fitted with a water atomiser, which produces a controlled, timed, but very brief, burst of a <1 Op droplet sized fog, immediately prior to ozone generation, to allow a very fine, but transient film of water to coat all available contact surfaces of any packaged ingredients, packaging and production consumable materials introduced into the sanitising chamber, into which the ozone can dissolve.

31. In the operation of the sanitising chamber (see Fig. 1), the sequence of actions is as follows: - * the door on the high care environment side of the cabinet is closed * the door on the low, or intermediate care environment side of the cabinet can then be opened * packaged ingredients, or packaging, or production consumable materials are then loaded into the sanitising chamber * the door on the low, or intermediate care environment side of the cabinet is then closed * the appropriate ozone sanitising cycle time is selected and switched on by operating the "START' button * the selected ozone sanitising cycle runs to completion * the 60 second sanitising chamber ozonated atmosphere exhaust cycle then starts and runs to completion * the lock on door on the high care environment side of the cabinet is then released * the door on the high care environment side of the cabinet is then opened * the, now sanitised, packaged ingredients, or packaging, or production consumable materials are then unloaded from the sanitising chamber.

32. To ensure safe operating use of the sanitising chamber, the following processor- controlled safeguards have been installed: - * ozone generation will only take place when both doors of the cabinet are closed and locked * both doors of the cabinet will remain locked while ozone generation is taking place * to avoid exposing operatives to excessive levels of ozone when unloading material from the sanitising chamber, both doors will remain locked for a further 60 seconds once ozone generation has ceased to allow residual ozone to be removed by an extraction fan exhausting the ozonated atmosphere within the chamber through an active carbon filter * control panels on each end of the cabinet have a triplet of illuminated indicators which will show; green when a door is unlocked and can be opened red when a door is closed and locked amber while ozone is being generated * to avoid the possibility of unintended, or intended, abuse of the system, once programmed, the cabinet can only be operated by a limited selection of cycle times and a simple START' switch * If power is removed, any door that IS closed and locked will automatically remain locked until power is restored.

33.To avoid misuse i.e., the introduction of materials from a low, or intermediate care environment to a high care environment, without operating the ozone sanitising procedure. a microprocessor-controlled interlock system, which controls the magnetic door locks, is employed to ensure the following safeguards are in place: * only one of the two doors of the cabinet is able to be opened at any one time, thus both doors are not able to be open at the same time * the door on the high care environment side of the cabinet can be opened only after an ozone sanitising cycle has been completed and the ozonated atmosphere within the sanitising chamber exhausted through an active carbon fter * the door on the high care environment side of the cabinet can be opened only if the door on the low care environment side is closed * the door on the low care environment side of the cabinet can be opened only if the door on the high care environment side is closed * the door on the low care environment side of the cabinet can only be opened, after an ozone sanitising cycle, once the door on the high care environment side has been opened, and then re-closed, to allow the cycle to be repeated * If power is removed, any door that is closed and locked will automatically remain locked until power is restored

Summary of the Invention

34.The device in this invention consists of a cabinet, which provides a chamber, through which packaged ingredients, packaging and production consumable materials are able to be surface sanitised with ozone during a carefully controlled transit from a low or intermediate care to a high care food production environment.

35. The cabinet is fabricated throughout from food contact grade 306 stainless steel and wifl be constructed to dimensions designed to meet the particular requirements of individual installations.

36 To allow hose-down' cleaning, the cabinet is constructed with welded seams and any surface mounted electrical/electronic controls or indicators are water-proof.

37.The cabinet has a sanitising chamber, accessible from both the low or intermediate care environment and the high care environment, by a door at each end.

38.The sanitising chamber is constructed with an inner perforated, dimple-profiled, sheet steel liner, suspended and separated from the floor, walls and ceilings to allow both the unrestricted circulation of ozone and its optimised surface contact with materials contained within.

39. Each door is fitted with vapour seals to minimise the risk of ozone escaping from the chamber into the working environment 40. Each door is fitted with processor-controlled, magnetic door locks.

41 The cabinet is fitted with an ozone generator, which, using air as a source of oxygen, is capable of generating ozone within the sanitising chamber of up to I 500mg/hr, or alternatively, using a food grade oxygen supply as the source of oxygen, the ozone generator is capable of generating up to 4500mg of ozone per hour.

42. Ozone generated at 1500mg/hr within the sanitising chamber, for an appropriate cycle period, will achieve up to a log 3 reduction in the initial contaminating populations of common human pathogenic, or food spoilage organisms.

43.The air/oxygen flow through the ozone generator is pumped to ensure a uniform distribution of ozone within the atmosphere of the sanitising chamber.

44.Once ozone generation has ceased, an extraction fan will start operating and continue doing so for a further 60 seconds to allow the atmosphere of the sanitising chamber to be exhausted through an active-carbon filter in order to effect the removal of residual ozone before the sanitising chamber is opened.

45. In order to monitor the ozone concentration within the sanitising chamber, the cabinet is fitted with a self-sealing port, to allow extraction sampling of the ozonated atmosphere.

46. In another aspect of this invention, to increase, if required, the biocidal efficiency of ozone in surface sanitisation, a timed, very brief, burst of a <lOp droplet sized fog, produced immediately prior to ozone generation.

47. In another aspect of this invention, if power is removed from the cabinet, either n.tentionaHy or unintentionally, any door that is closed and locked will automatically remain locked until mains power is restored.

48. To ensure the safe operation of the cabinet, ozone generation is under processor control and can only take place when both doors of the cabinet are closed and locked. In addition, these doors will remain locked for a further 60 seconds after ozone generation has ceased in order to allow residual ozone to be removed by exhausting the atmosphere within the chamber through an active carbon filter.

49.To avoid the possibility of unintended, or intended, abuse of the system, once programmed, the cabinet can only be operated through a limited selection of cycle times.

5OTo prevent misuse a processor-controlled interlock system is employed to ensure that only one of the two doors of the cabinet is able to be opened at any one time.

Also the door on the high care environment side of the cabinet can be opened only after an ozone sanitising cyc'e has been completed and only if the door on the low care environment side remains closed and locked In addition, the door on the low care environment side of the cabinet, after an ozone sanitising cycle, can only be opened once the door on the high care environment side has been opened, and then re-closed, to allow a repeat of the cycle.

Claims

Claims I A cabinet designed to provide a chamber, through which

packaged ingredients, packaging and production consumable materials are transferred safely, with controlled surface sanitising by ozone, from a low, or intermediate care environment to a high care environment within a food production facility.

In another aspect of this invention, the atmospheric concentrations of ozone and the contact times provided within the device are programmed to achieve an, up to log 3, reduction in the initial surface contaminating populations of a range of human pathogenic or food spoilage organisms. In another aspect of this invention, to ensure safe operation and to prevent misuse a processor-controlled interlock system is installed within the device, which imposes the correct sequencing of both ozone generation and door closures secured by magnetic locks.

2. The low o intermediate care to a high care environment, ozone surface sanitising, transit device according to claim I, wherein the cabinet is fabricated throughout from food contact grade 306 stainless steel.

3. The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1, wherein the cabinet is constructed to dimensions designed to meet the particular requirements of individual installations.

4. The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1, wherein the cabinet is constructed with welded seams and any surface mounted electrical/electronic controls or indicators are water-proof to allow hose-down' cleaning, The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1, wherein the cabinet is constructed with a sanitising chamber, which is accessible from both the low or intermediate care environment and the high care environment, by a door at each end 6. The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 5. wherein the both doors of the sanitising chamber are fitted with vapour seals to minimise the risk of ozone escaping from the chamber into the working environment.

7. The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 5, wherein both doors of the sanitising chamber are fitted with processor-controlled, magnetic locks.

8. The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 5, wherein the sanitising chamber is constructed with an inner perforated, dimple-profiled, sheet steel liner, suspended and separated from the floor, walls and ceiling to allow both the unrestricted crcutation of ozone and its optimised surface contact with materials contained within.

9 The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1, wherein the sanitising chamber is fitted with an ozone generator, which, using air as a source of oxygen, is capable of generating ozone within the sanitising chamber at levels of up to 1500mg/hr.

lOThe low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 9, wherein the sanitising chamber is fitted with an ozone generator, which using a food grade oxygen supply as the source of oxygen, is also capable of generating ozone within the sanitising chamber at levels of up to 4500mg/hr 11.The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 9, wherein the air/oxygen flow through the ozone generator is pumped to ensure a uniform distribution of ozone within the atmosphere of the sanitising chamber.

12.The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 9, wherein the operation of the ozone generator is controlled by a processor providing a limited number of pre-set cycle times.

13.The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 9, wherein, immediately post ozone generation, an extraction fan will start operating and continue doing so for a further 60 seconds after ozone generation has ceased, exhausting the atmosphere of the sanitising chamber through an active-carbon filter.

14. The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 9, wherein, to increase, it required, the micro-biocidal efficiency of ozone surface sanitisation, the cabinet is fitted with a water atomiser, which produces a controlled, timed, but very bnef, burst of a <1 Op droplet sized fog, immediately prior to ozone generation.

15.The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1, wherein the cabinet is fitted with a self-sealing port, to allow sampling of the atmosphere within the sanitising chamber in order to monitor the ozone concentration.

16. The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1, wherein, if power is removed from the cabinet, either intentionally or unintentionally, any door that is closed and locked will automatically remain locked until mains power is restored 17 The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1 wherein, to ensure the safe operation of the cabinet, ozone generation is under microprocessor control and can only take place when both doors of the cabinet are closed and locked. In addition, these doors will remain locked for a further 60 seconds after ozone generation has ceased in order to aVow residual ozone to be removed by exhausting the atmosphere within the chamber through an active carbon filter.

18.The tow or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1, wherein, to avoid the possibility of unintended, or intended, abuse of the system, once programmed, the cabinet can only be operated through a timited selection of cycle times.

19 The low or intermediate care to a high care environment, ozone surface sanitising, transit device according to claim 1, wherein to prevent misuse i.e., the introduction of materials from a low, or intermediate care environment to a high care environment, without operating the ozone sanitising procedure, a microprocessor is installed, which imposes the correct operational sequencing of ozone generation, door closures and door locking.