BE1030127B1 - DEVICE, SYSTEM AND METHOD FOR DISINFECTING A ROOM - Google Patents

Abstract

Atomizing device (200) for atomizing a hydrogen peroxide mixture, comprising: a first fluid circuit having a first pump (205), and a first inlet (IN1) for receiving a first gas stream from the chamber, and having means to remove droplets from a adding hydrogen peroxide mixture to this first gas stream, and having a first outlet (OUT1) for supplying this first gas stream with these droplets to the chamber; a controller (215) for controlling the first pump; a replaceable reservoir (202) containing a hydrogen peroxide mixture; the reservoir carrying an RFID tag (203) containing a value corresponding to the amount of hydrogen peroxide mixture in the reservoir; an RFID reader-writer (204) to read data from the RFID tag; and wherein the control unit is arranged to repeatedly update the amount of hydrogen peroxide mixture on the RFID tag to indicate the remaining amount, taking into account variable flow rate depending on the amount still present.

Description

DEVICE, SYSTEM AND METHOD FOR DISINFECTING A ROOM

Domain of the invention

The present invention generally relates to the field of apparatus and systems for disinfecting or disinfecting rooms or premises or the like, and more specifically to an atomizing apparatus for atomizing a hydrogen peroxide mixture, and a system comprising such apparatus, and a process performed by such a device.

Background of the invention

Methods and devices for disinfecting or sterilizing rooms by circulating a gas stream containing hydrogen peroxide to kill microorganisms such as e.g. viruses, bacteria, fungi, spores and yeasts are known in the art.

EPO774263(A1) and EP2952475(A1) describe such methods and devices.

There is always room for improvements or alternatives.

Summary of the invention

It is an object of the present invention to provide a nebulizing device for disinfecting a room or a room or the like.

It is an object of embodiments of the present invention to provide a fogging device capable of achieving kill for a broad spectrum of microorganisms, e.g. as specified in standard EN17272.

It is an object of embodiments of the present invention to provide a nebulizer device capable of achieving kill for a broad spectrum of microorganisms, e.g. as specified in standard EN17272, in a shortened time span (counted from the start of the disinfection cycle until the room is made available again for normal use).

It is an object of embodiments of the present invention to provide a nebulizing device with good or improved reliability, e.g. a device that indicates that an intended disinfection process can/cannot be performed reliably under given circumstances and with the available means, or performed.

It is an object of embodiments of the present invention to provide a device with a relatively simple structure, e.g. simple hardware.

It is an object of embodiments of the present invention to provide a device that accurately manages the amount of disinfectant.

It is an object of embodiments of the present invention to provide a device that efficiently manages the amount of hydrogen peroxide mixture, e.g. that uses less or as little hydrogen peroxide mixture as possible to achieve a target kill.

It is an object of embodiments of the present invention to provide an apparatus with which a disinfection cycle can be performed in a controlled manner, even if at least one of the hydrogen peroxide mixture reservoirs is not completely filled.

It is an object of embodiments of the present invention to provide a device that poses a low security risk to the user and his/her immediate environment.

It is an object of embodiments of the present invention to provide a device that is simple to use, and/or that is easy to use.

It is an object of embodiments of the present invention to provide an apparatus that allows a room or a room or hall (e.g., a conference room) with a volume of up to about 145 m? can be reliably sterilized.

It is an object of embodiments of the present invention to provide an apparatus that allows a room or a room or hall (e.g., a conference room) with a volume of up to about 750 m? can be reliably sterilized.

These and other objects are achieved by an nebulizer device according to embodiments of the present invention.

According to a first aspect, the present invention provides an atomizing device for atomizing a hydrogen peroxide mixture for disinfecting a room, the atomizing device comprising: a first fluid circuit having a first pump, and having a first inlet for receiving a first gas stream from the chamber, and with means for adding droplets (e.g. 20 to 30 microns in average diameter) of a hydrogen peroxide mixture to this first gas stream, and with a first outlet for delivering this first gas stream with these droplets to the chamber ; a controller for controlling the first pump; wherein the nebulizing device has at least one connection for connecting at least one replaceable container of a hydrogen peroxide mixture to the first circuit; and wherein the at least one reservoir carries an RFID tag that stores data comprising at least an amount of the hydrogen peroxide mixture; and wherein the nebulizer device further comprises at least one RFID reader-writer communicatively connected to the control unit and arranged to read data from the RFID tag of the at least one reservoir; and wherein the controller is further configured to repeatedly write to the RFID tag to update the amount of hydrogen peroxide mixture on the RFID tag of the at least one reservoir.

It is a great advantage that the replaceable reservoir contains an RFID tag, and that the nebulizer device contains an RFID reader-writer, as this way information from the hydrogen peroxide mixture can be passed to the device without human intervention, thus with a reduced chance on errors.

The RFID tag makes it possible, among other things, to check whether the reservoir contains the correct content, or in other words, to detect whether a reservoir with the wrong mixture has been connected.

The RFID tag contains the initial amount of hydrogen peroxide mixture (e.g. 1000 ml, or 3000 ml), and the control unit is arranged to repeatedly update or keep this amount up-to-date, so that the RFID tag at any time remaining amount of the hydrogen peroxide mixture in the reservoir. In this way, the atomizing device can check whether there is sufficient hydrogen peroxide mixture present before starting a new disinfection cycle. In this way, the RFID tag can therefore help to successfully complete a disinfection cycle and waste as little hydrogen peroxide mixture as possible.

The control unit is further provided for updating the amount of hydrogen peroxide mixture, taking into account a variable flow rate of the liquid mixture, the flow rate being dependent on the amount of hydrogen peroxide mixture still present in the at least one reservoir.

Although it is in principle possible to update the contents of the reservoir only once at the end of a disinfection cycle, it is an advantage to update the contents repeatedly, e.g. periodically, e.g. at least once per minute, or at least once every 30 seconds, or at least once every 15 seconds, or at least once every 10 seconds, as this increases the risk of a large discrepancy between the actual amount of the hydrogen peroxide mixture on the one hand, and the amount as indicated on the RFID tag, on the other hand, is drastically reduced, even in the event of a power failure.

It is an advantage to communicate contactlessly (via RFID) as opposed to galvanic contact, due to the corrosivity of the mixture.

The use of an RFID tag also ensures that a user cannot use a product that the device is not familiar with, or with which the device cannot perform proper disinfection, e.g. a hydrogen peroxide mixture of too low a concentration (e.g. with only 3 wt. % H2 O2 concentration).

The use of an RFID tag on the reservoir also ensures that if a user were to place a half-full reservoir in another similar nebulizer device, the device would automatically recognize that this reservoir is only half full.

The first pump preferably has a constant, predetermined flow rate.

In one embodiment, the control unit is further provided for: c) determining or receiving a volume of the room to be disinfected; d) determining the concentration of hydrogen peroxide in the hydrogen peroxide mixture in the at least one reservoir; e) estimating an amount of hydrogen peroxide mixture required to introduce a predetermined gaseous hydrogen peroxide concentration into the room (e.g. during a first phase of a disinfection cycle), and to maintain it for a predetermined contact time (e.g. during a second phase 2); f) determining how much hydrogen peroxide mix is available in the at least one reservoir; g) giving an error message if the amount of hydrogen peroxide mixture present is less than the required amount of hydrogen peroxide mixture.

The RFID tag therefore helps to guarantee the reliability of a "successful disinfection cycle" by giving an error message before a cycle is started.

In one embodiment, the necessary amount of hydrogen peroxide mixture is based on the following formula: NH = KV * A, where NH is the necessary amount of hydrogen peroxide mixture (expressed in ml), and where KV is the volume of the chamber (expressed in cubic meters), and where

A is a value (expressed in ml/m3) that depends on the hydrogen peroxide concentration in the hydrogen peroxide mixture.

In one embodiment, the required amount of hydrogen peroxide mixture is determined based on the following formula: NH = KV * A, where NH is the required amount of hydrogen peroxide mixture (expressed in ml), and where KV is the volume of the chamber (expressed in cubic meters) , and where A is a value (expressed in ml/m3) calculated on the basis of the hydrogen peroxide concentration in the hydrogen peroxide mixture, and one or more of the following parameters: Tchamber, RVchamber and Vchamber, where Tchamber is the temperature of the chamber ,

RVroom is the relative humidity of the room, and Vroom is the volume of the room to be disinfected.

In one embodiment, the nebulizer device comprises at least one reservoir of a silver stabilized hydrogen peroxide mixture.

Tests have shown that a silver-stabilized hydrogen peroxide mixture is many times more stable (decomposes less quickly) than a hydrogen peroxide mixture that does not contain silver ions.

In one embodiment, the hydrogen peroxide mixture consists of hydrogen peroxide and demineralized water and silver ions. This mixture therefore does not contain any other substances such as chlorine or peracetic acid.

In one embodiment, the ratio of weight percent hydrogen peroxide to weight percent silver ions in the silver stabilized hydrogen peroxide mixture is a value in the range of 1500 to 2000, preferably in the range of 1600 to 1900.

In one embodiment, the data on the RFID tag of the at least one container further contains a value of a concentration of hydrogen peroxide in the hydrogen peroxide mixture; and the control unit of the nebulizer is further provided to read this concentration value stored on the RFID tag.

This value can e.g. be used to calculate the necessary amount of hydrogen peroxide mixture to be atomized in the first and second phase to disinfect a certain room. This value can also be used during the disinfection cycle itself, e.g. to determine the duration T1 of the first phase, and/or to determine the duty cycle of the second phase.

By storing the hydrogen peroxide concentration of the hydrogen peroxide mixture on the

RFID tag, the nebulizer can optimally take into account the hydrogen peroxide mixture.

This greatly increases the flexibility of the device, as it can work with different hydrogen peroxide mixtures.

In one embodiment, the data on the RFID tag of the at least one reservoir further includes a best-before date, and the nebulizer device is provided to determine the current date (e.g., requestable from an external device such as a smartphone or a laptop, or by reading out a local clock}, and comparing the current date with the best before date, and giving an error message if the best before date has passed.

By checking the expiration date of the reservoir, or if several reservoirs are present, of each reservoir, the reliability of effective disinfection or killing of microorganisms such as viruses, bacteria, fungi, spores and yeasts can be increased.

In one embodiment, the data on the RFID tag of the at least one reservoir further includes a date of manufacture or a best-before date, and the nebulizer device is provided (e.g., requested from an external device such as a smartphone or a laptop, or by local clock from read) to determine the current date, and is provided to adjust the concentration of the hydrogen peroxide mixture read from the RFID tag in function of the production date or best before date on the one hand, and the current date on the other hand.

In one embodiment, the nebulizer device further comprises a first valve for selectively connecting a first replaceable reservoir to the first fluid circuit, and further comprising a second valve for selectively connecting a second replaceable reservoir containing a second hydrogen peroxide mixture to the first fluid circuit; and the second reservoir has a second one

RFID tag storing data containing at least an amount of the second hydrogen peroxide mixture; and the control unit is further provided to repeatedly update the RFID tag of the container from which hydrogen peroxide mixture is withdrawn.

For example, for a nebulizer with two hydrogen peroxide mixture reservoirs, this could mean that the RFID tag of the first reservoir is updated repeatedly when the first pump is active and the first valve is open and the second valve is closed, and the RFID tag of the second reservoir is updated repeatedly when the first pump is active and the first valve is closed and the second valve is open.

It is a great advantage to use a nebulizer with a connection for two reservoirs, because this avoids the loss of hydrogen peroxide mixture (or rather: leaving it unused), and because it avoids that a user has to pour over hydrogen peroxide mixture, with all the associated risks. This also makes it possible to disinfect a larger room (or space).

By using two reservoirs, the control unit can switch from the first to the second reservoir at a convenient time, in order to lose as little hydrogen peroxide mixture as possible (leave it unused).

In an atomization device according to the present invention, the two reservoirs are not used simultaneously to atomize hydrogen peroxide mixture, but either the first reservoir or the second reservoir. The first and second valves allow choosing which of the two reservoirs is connected to the mouthpiece (or mouthpieces). These valves are controlled by the control unit. The RFID tag of the reservoir that is fluidly connected is updated repeatedly.

In one embodiment, the nebulizer device includes a first RFID reader-writer arranged to communicate only with the RFID tag of the first container; and the nebulizer includes a second RFID reader-writer arranged to communicate only with the RFID tag of the second container.

It is an advantage to use two separate RFID reader-writers, one for each reservoir, because the control unit can determine how much fluid each reservoir contains, without human intervention. In this way, the risk of human error is reduced or completely eliminated, thus increasing the reliability of a successful disinfection cycle.

In one embodiment, the atomizing device further comprises an electromagnetic shielding to prevent the first RFID reader-writer from communicating with the RFID tag of the second container, and vice versa, or to reduce interference.

In one embodiment, the RFID tag is a passive RFID tag operating at a frequency of 13.56 MHz.

Testing has shown that such an RFID tag is effective over a sufficient distance from the reservoir, and can provide sufficient power to read and write data reliably, at a sufficiently high read/write speed.

In one embodiment, the communication between the RFID tag and the RFID reader-writer is encrypted.

It is an advantage to encrypt the communication with the RFID tag to prevent the data on the tank from being accidentally changed or deleted by an unauthorized user. This helps to guarantee the reliability of a "successful disinfection cycle".

It should be noted that it is not necessary for all information to be encrypted. For example, the invention would still work if one or more of the values selected from the group consisting of the product name, concentration, and expiration date were unencrypted on the RFID chip. For example, this would allow an employee with a smartphone (or other device that supports NFC communication) to read the RFID of a reservoir before inserting it into the nebulizer.

In a specific embodiment, at least one of: the product name, the concentration, and the expiration date are stored both encrypted and unencrypted on the RFID tag.

In one embodiment, the RFID tag of each replaceable container of hydrogen peroxide mixture has a memory of at least 512 bytes, or at least 1024 bytes.

Although not all bytes are available for the fogging device, such an RFID tag is very suitable for the current application. Preferably an RFID tag with an EEPROM memory is used, because it allows to overwrite the "amount of mixture", although this is not strictly necessary, and it is also possible to work with an RFID tag of which not every byte can be individually overwritten without erasing an entire sector. The latter would be significantly more complex in terms of software.

In one embodiment, the control unit is further provided to update the amount of hydrogen peroxide mixture of the RFID tag of the at least one reservoir at least once per minute when liquid is withdrawn from the respective reservoir, preferably at least 2x or at least 3x or at least 5x per minute that the first pump is active and the first or second valve is open.

Of course, the quantity is not updated if the first pump is OFF, or if the third reservoir (for flushing) is used.

In one embodiment, the first pump has a fixed (predetermined) speed, and the control unit is arranged to switch the first pump either ON or OFF; and the first fluid circuit is provided to add the hydrogen peroxide mixture droplets to the first air stream based on the Venturi principle.

As a result, a liquid pump can be avoided, which contributes to the simplicity of the nebulizer. It is a very important advantage that the liquid does not need to be heated. This drastically reduces the risk of explosion. A disadvantage of this is that the flow rate of the liquid flow is not constant, but depends on the actual amount of liquid in the reservoir, but because the amount of liquid is updated repeatedly (e.g. periodically), the nebulizer can still determine very precisely what the fluid flow rate.

In a preferred embodiment, the velocity of the first gas stream is a velocity of 50 to 70 m/s (e.g. about 60 m/s), and the suction channel of the liquid mixture has an internal diameter of 5 to 7 mm (e.g. 6 mm ).

In one embodiment, the control unit is provided to update the amount of hydrogen peroxide mixture, taking into account a variable flow rate of the liquid mixture, the flow rate being dependent on the amount of hydrogen peroxide mixture still present in the at least one reservoir.

In a preferred embodiment, the flow rate of the liquid withdrawn from the reservoir varies by a factor of at least 1.5 (150%) between a substantially full reservoir and a substantially empty reservoir, or by a factor of at least 160%, or by a factor of at least 170%, or by a factor of at least 180%, or by a factor of at least 190%.

It is not trivial to accurately calculate the amount of fluid remaining in the reservoir for a suction based on the Venturi principle, but accurate estimation of the amount remaining is important to obtain an optimal compromise between: i) sufficient kill ii) to waste as little hydrogen peroxide mixture as possible (or in other words: to use the amount of hydrogen peroxide mixture present as optimally as possible}, iii) to carry out the shortest possible disinfection cycle, iv) to maintain a constant or substantially constant hydrogen peroxide concentration during the second phase (the "contact phase") in open-loop control.

In one embodiment, the remaining amount of hydrogen peroxide mixture in the at least one reservoir is calculated iteratively, taking into account the initial content and assuming that the instantaneous flow rate changes linearly as a function of the amount of hydrogen peroxide mixture in the at least one reservoir between a first value associated with a substantially full reservoir and a second value associated with a substantially empty reservoir.

This implies that the amount of mixture in the reservoir varies non-linearly as a function of the time that liquid is drawn from the reservoir.

FIG. 6 shows a measurement of the flow rate of a prototype atomizer. In this example, the first value (corresponding to a full reservoir) is about 62 ml/min, and the second value (corresponding to a nearly empty reservoir) is about 30 ml/min.

FIG. 7 and FIG. 8, derived from FIG. 6, show that the flow rate and the volume of liquid mixture remaining in the reservoir change non-linearly as a function of the time that liquid mixture is withdrawn from the reservoir.

FIG. 8 further shows that the time required to extract 500 ml of liquid mixture from an almost full reservoir (in the example 500 sec) differs very strongly from the time required to extract the same amount of liquid mixture from an almost empty reservoir (in the example: 790 seconds).

In practice, this can be implemented by using a lookup table with at least two columns, where one column contains the cumulative time that liquid mixture is withdrawn from the reservoir (or in other words: that the first pump is active, and the relevant valve is open), and a second column containing the remaining amount of hydrogen peroxide mixture. For example, the table can contain values for discrete time intervals of multiples of 10 seconds, or multiples of 20 seconds, or multiples of 30 seconds, or multiples of 1 minute, but of course a table of other intervals can be used. Optionally, values from the table can be interpolated. Alternatively, it is also possible to calculate the variable flow rate and/or the remaining amount of liquid using mathematical formulas.

In one embodiment, the nebulizer has a second fluid circuit with a second pump, and with a second inlet for receiving a second gas stream from the chamber, and with means for removing hydrogen peroxide from the second gas stream, and with a second outlet for supplying this second gas stream of reduced hydrogen peroxide concentration to the chamber.

It is an advantage of these agents that they actively extract hydrogen peroxide from the air of the room. In this way, the H202 concentration in the chamber can be lowered more quickly, and the chamber can be released again more quickly. Typically, this reduces the time of the third stage by a factor of about two.

In one embodiment, the means for removing hydrogen peroxide from the second gas stream comprises a catalyst.

The catalyst may be, e.g., a metal catalyst, e.g., a platinum/alumina catalyst, or a ruthenium/alumina catalyst, but the invention is not limited thereto, and another catalyst may also be used.

In one embodiment, the means for removing hydrogen peroxide from the second gas stream comprises a scrubber.

The scrubber can, for example, comprise an active carbon filter.

In a second aspect, the present invention also provides an atomization system comprising: an atomization apparatus according to the first aspect; and one or more external devices selected from: a hydrogen peroxide sensor, a temperature sensor, a relative humidity sensor, a remote control, a fan or a ventilator, an air heater, a dehumidifier, an external scrubber, a laptop or a tablet or a smartphone, where the external device is communicatively connected to the control unit of the nebulizer device.

The communicative connection can be a cable connection (e.g. USB, Ethernet,

RS232, etc.) or can be a wireless connection, e.g. an RF connection (e.g. Bluetooth, Wifi}, or an optical connection (infrared).

In the case of a sensor, the control unit may be arranged to receive data from the sensor, and use this value to perform the disinfection process.

In the case of a remote control, the control unit may be arranged to receive and execute commands from the remote control, e.g. starting or stopping a disinfection cycle, after all persons have left the room.

In the case of auxiliary devices (fan, air heater, dehumidifier, scrubber), the control unit can be arranged to selectively activate and/or deactivate these devices.

In the case of a processing unit (e.g. laptop, tablet or smartphone or similar), the control unit may be provided to receive data (e.g. one or more of: settings such as a character string with the name of the room, date and time, sensor data, contents of the reservoir(s), etc.) to this device, which can then display this data on a screen, or store (logging) on a local storage medium (e.g. hard disk or USB stick or similar).

Specific and preferred aspects of the invention are included in the appended independent and dependent claims. Features of the dependent claims may be combined with features of the independent claims and with features of other dependent claims as appropriate and not merely as expressly set forth in the claims.

These and other aspects of the invention will become apparent and elucidated with reference to the embodiments described below.

Brief description of the drawings

FIG. 1A shows a first example of a fogging device according to an embodiment of the present invention, also referred to herein as a "small fogger", in perspective view. A container with a hydrogen peroxide mixture is connected to the nebulizer. The reservoir contains an RFID tag containing a field that displays the amount of hydrogen peroxide in the reservoir. The nebulizer has an RFID reader-writer provided to keep this quantity up to date.

FIG. 1B shows the reservoir of FIG. 1A with an RFID tag. The RFID tag is also enlarged with increased contrast.

FIG. 2 shows a block diagram of a possible embodiment of the nebulizer device of FIG. 1A.

FIG. 3A shows a second exemplary fogging device according to an embodiment of the present invention, also referred to herein as a "large fogger", in perspective view. There is space in the device for at least two containers with a hydrogen peroxide mixture. Each reservoir has an RFID tag containing a field that displays the amount of hydrogen peroxide in the respective reservoir. The nebulizer contains two

RFID reader-writers, each provided to communicate with one RFID tag. The device is provided to keep the quantities indicated in the RFID tags up to date.

FIG. 3B and FIG. 3C show an example of a reservoir that may be used in conjunction with the nebulizer device of FIG. 3A. The RFID tag is also enlarged with increased contrast.

FIG. 4 shows a block diagram of a possible embodiment of the nebulizer device of FIG. 3A.

FIG.5 shows a fogging system comprising a fogging device according to an embodiment of the present invention, and one or more external devices selected from: a hydrogen peroxide sensor, a temperature sensor, a relative humidity sensor, a remote control, at least one fan or ventilator, an air heater, a dehumidifier, an external scrubber, a laptop or a tablet or a smartphone, the external device being operationally and/or communicatively connected to the control unit of the fogging device.

FIG. 6 shows an exemplary curve illustrating the flow rate of the liquid hydrogen peroxide mixture from the reservoir as a function of the degree of filling of the reservoir, as applicable in atomizing devices according to the present invention that utilize the venturi effect.

FIG. 7 shows another representation of the curve of FIG. 6, showing the fluid flow rate as a function of the cumulative time of emptying a reservoir.

FIG. 8 shows a curve representing the contents of a 3000 ml reservoir, as a function of cumulative time, corresponding to the fluid flow rate of FIG. 6, illustrating, for example, that it takes much less time to withdraw 500 ml of liquid mixture from a full reservoir than from one that is almost empty. This curve shows that, in order to obtain a good estimate of the flow rate of the liquid mixture, a good knowledge of the contents of the reservoir is necessary. In other words, this curve shows that a good knowledge of the contents of the reservoir is necessary to make a good estimate of the time it takes to withdraw a certain amount of mixture from the reservoir.

FIG. 9A shows three curves representing the maximum gaseous hydrogen peroxide concentration that can be achieved by so-called "cold fogging" (i.e., nebulizing without heating the liquid mixture), as a function of ambient temperature and relative humidity in a room.

FIG. 9B shows a curve representing the minimum room temperature as a function of relative humidity to achieve a gaseous hydrogen peroxide concentration of 100 ppm in the room by "cold fogging" a hydrogen peroxide mixture containing approximately 87.5 weight percent water and approximately contains 12.5 wt% hydrogen peroxide.

FIG. 10 to FIG. 13 illustrate a method that can be performed by an atomizing device according to the present invention.

FIG. 14A is an exemplary representation of an ideal concentration curve of

H202 in gaseous form in the room, during a disinfection process.

FIG. 14B is an exemplary representation of a possible field course of the concentration of gaseous H 2 O 2 in the chamber during a disinfection process performed by a nebulizer according to an embodiment of the present invention in "open-loop" (i.e., without measurement of the gaseous H202 concentration in the chamber).

FIG. 14C is an exemplary representation of a possible field course of the concentration of gaseous H 2 O 2 in the chamber during a disinfection process performed by a nebulizer according to an embodiment of the present invention in "closed loop" (i.e., with measurement of the gaseous H202 concentration in the chamber).

FIG. 15A shows an example of "intermittent fogging" with a fixed interval time and a fixed duty cycle.

FIG. 15B shows an example of "intermittent fogging" with a fixed interval time and a variable duty cycle.

Detailed description of illustrative embodiments

The present invention will be described with respect to particular embodiments and with reference to certain drawings, however, the invention is not limited thereto but is limited only by the claims. The figures are only schematic and not limiting. In the drawings, the size of certain elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and relative dimensions sometimes do not correspond to the actual practice of the invention.

Furthermore, the terms first, second and the like are used in the description and in the claims to distinguish like elements and not necessarily to describe an order, whether temporal, spatial, ranking or otherwise. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are adapted to operate in any order other than that described or illustrated herein.

It should be noted that the term "comprises", as used in the claims, should not be construed as limited to the means described below; this term does not exclude other elements or steps. It should therefore be interpreted as specifying the presence of the referenced features, values, steps, or components listed, but does not preclude the presence or addition of one or more other features, values, steps, or components, or groups thereof. device comprising means A and B" should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, A and B are the only relevant components of the device.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a specific feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, occurrences of the terms "in one embodiment" or "in one embodiment" in various places throughout this specification may not necessarily all refer to the same embodiment, but may do so. Furthermore, the specific features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

Similarly, it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together into a single embodiment, figure or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one. or more of the various inventive aspects. In any event, this method of disclosure should not be interpreted as reflecting an intent that the invention requires more features than are explicitly stated in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single previously disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim being self-contained as a separate embodiment of this invention.

Further, while some embodiments described herein contain some, but not others, features included in other embodiments, combinations of features of different embodiments are intended to be within the scope of the invention, and constitute different embodiments, as would be understood by those skilled in the art. .

For example, in the following claims any of the described embodiments may be used in any combination.

Numerous specific details are set forth in the description provided herein. In any case, it is to be understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures, and techniques have not been shown in detail for the sake of clarity of this disclosure.

In this document, “fogging device” is also referred to as “fogger”, “disinfection device” and “sterilization device”.

In this document, the term "room" is used for an enclosed space. For example, this term can refer to a hospital room, a meeting room in a company, etc.

References in this document to "humidity" or "humidity", without reference to absolute humidity or relative humidity, mean the relative humidity of the room air.

In this document, the terms "fogging" and "fogging" are used synonymously.

In this document the terms "liquid mixture" and "hydrogen peroxide mixture" are used synonymously.

In this document, the terms "disinfection cycle" and "disinfection process" are used synonymously.

When referring to "hydrogen peroxide concentration in the chamber" in this document, it means the hydrogen peroxide concentration in gaseous form, unless explicitly stated otherwise, or unless clear from the context that something else was intended.

When referring to "hydrogen peroxide concentration in the mixture" in this document, it means the hydrogen peroxide concentration in liquid phase, unless explicitly stated otherwise, or unless clear from the context that something else was intended.

The present invention relates to devices and systems for sanitizing or disinfecting rooms or premises or the like, and more specifically to a device for atomizing a hydrogen peroxide mixture, e.g., a silver stabilized hydrogen peroxide mixture, and a system comprising such device.

It is known in the art that hydrogen peroxide (chemical formula: H202) is suitable for killing micro-organisms such as viruses, bacteria, fungi, spores and yeasts. In practice, a mixture is usually used in which hydrogen peroxide (H202) is dissolved in demineralized water (H,O), and the nebulizer must ensure that "appropriate amounts" of this mixture are introduced into the room. Much less known is how much that “appropriate amount” must be to achieve a certain kill rate (e.g. LOG5).

Different manufacturers offer different solutions. For example, the concentration of hydrogen peroxide (H202) varies from about 5 wt% to about 35 wt% relative to the mixture. Some manufacturers atomize the mixture without heating ("cold atomization"), other manufacturers heat or vaporize the mixture. However, the latter can be dangerous.

It is also known that the relative humidity and temperature of the room to be disinfected play an important role in the disinfection process. In general, the higher the temperature and the lower the relative humidity, the more water and hydrogen peroxide can be added to the air in the room. For this reason, some manufacturers of fogging devices build a heating component and/or a dehumidifier into their device to condition the room before starting fogging. This allows a higher concentration of hydrogen peroxide to be introduced into the chamber, but the disinfection process will take much longer.

However, the state of the art is much less clear about exactly how much hydrogen peroxide is needed to achieve a certain kill rate. Some manufacturers recommend raising the hydrogen peroxide level in the room to at least 400 ppm, and preferably much higher, e.g. at least 900 ppm. However, this has several drawbacks: (1) reaching such a high value is only possible if the room has a sufficiently high temperature and a sufficiently low humidity,

which in practice means that the room has to be conditioned, which requires extra hardware, and costs extra time and energy; (2) it takes longer to bring the hydrogen peroxide level in the chamber to this level (see, e.g., stage 1 in FIG. 14A); and (3) it takes much longer to reduce the hydrogen peroxide level in the room back to a safe level (see e.g. stage 3 in

FIG. 14A), which again takes extra time.

The inventors of the present invention had several objectives in mind, including: they wanted above all to provide a reliable solution, a solution that kills sufficiently (e.g. at least LOG5 as specified in the EN17272 standard), preferably with hardware that is as simple as possible, preferably with as little waste of hydrogen peroxide mixture as possible, and preferably by carrying out a process that is safe for the user and takes as little time as possible (the total time, counting from the start of the disinfection, up to and including the release of the the room), and preferably two or more of these objectives.

The present invention provides a nebulizing device 100, 200, 300, 400, 500 for nebulizing a hydrogen peroxide solution for disinfecting a room. The nebulizer includes a first fluid circuit with a first inlet "IN1" for receiving a first gas stream from the chamber, and means for adding droplets (e.g., 20-30 micron in diameter) of a hydrogen peroxide mixture to this first gas stream, and with a first outlet "OUT1" for supplying this first gas stream with these droplets to the chamber. The first fluid circuit includes a first pump 205, 405 to circulate air through the first circuit. The nebulizer further includes a control unit 215, 415 (e.g., a programmable microprocessor) for controlling the first pump 205, 405, e.g., to pump on and off. The atomizing device is further provided for connecting to the first circuit at least one replaceable reservoir 202, 4023, 402b containing a hydrogen peroxide mixture. The at least one reservoir carries an RFID tag 103, 303, which stores data comprising at least an amount of the hydrogen peroxide mixture. The nebulizer device further comprises at least one RFID reader-writer, which is communicatively connected to the control unit. The control unit is arranged to read data from the RFID tag of the at least one reservoir, and to repeatedly update (the field containing) the amount of hydrogen peroxide mixture on the RFID tag 103, 303 of the at least one reservoir, e.g. when the first pump 205, 405 is active.

It is a great advantage that the replaceable reservoir contains an RFID tag, and that the nebulizer device contains an RFID reader-writer, as this way information from the hydrogen peroxide mixture can be passed to the device without human intervention, thus with a reduced chance on errors.

The RFID tag makes it possible, among other things, to check whether the reservoir contains the correct content, or in other words, to detect whether the wrong reservoir has been connected.

It is an advantage that the RFID tag contains the initial amount of hydrogen peroxide mixture (e.g. 1000 ml, or 3000 ml), and that the control unit is equipped to repeatedly update this amount, or keep it up-to-date, so that the RFID tag indicates the remaining amount of the hydrogen peroxide mixture in the reservoir at any time. In this way, the nebulizer can check whether there is sufficient hydrogen peroxide mixture before starting a new disinfection cycle, e.g. in another room, and after interrupting the power supply.

In this way, the RFID tag can therefore help to successfully complete a disinfection cycle and waste as little hydrogen peroxide mixture as possible.

Although it is in principle possible to update the contents of the reservoir only once at the end of a disinfection cycle, it is an advantage to update the contents repeatedly, e.g. periodically, e.g. at least once per minute, or at least once every 30 seconds, or at least once every 15 seconds, or at least once every 10 seconds, as this increases the risk of a large discrepancy between the actual amount of the hydrogen peroxide mixture on the one hand, and the amount as indicated on the RFID tag, on the other hand, is drastically reduced, even in the event of a power failure.

It is an advantage to communicate contactlessly (via RFID) as opposed to galvanic contact, due to the corrosivity of the mixture.

The use of an RFID tag also ensures that a user cannot use a product that the device is not familiar with, or with which the device cannot perform proper disinfection, e.g. a hydrogen peroxide mixture of too low a concentration (e.g. with only 3 wt. % H2 O2 concentration).

The use of an RFID tag on the reservoir also ensures that if a user were to place a half-full reservoir in another similar nebulizer device, the device would automatically recognize that this reservoir is only half full.

The RFID tag also allows a device with at least two reservoirs to start a disinfection cycle with a reservoir that is not completely filled. The user therefore does not have to throw away the hydrogen peroxide mixture (economical or efficient use), or pour it over (safety), and the device is still able to introduce the correct amount of hydrogen peroxide into the chamber (reliability). This is particularly non-trivial for a device without a liquid pump, but where the liquid is drawn from the reservoir by the Venturi principle.

This is the main underlying principle of the present invention. Further embodiments and variants are described in more detail below.

Referring to the figures,

FIG. 1A shows a first example of a fogging device 100, also referred to herein as a "small fogger", in perspective view. A container 102 containing a hydrogen peroxide mixture is connected to the fogging device 100. As can be seen, the container 102 is located on the outside of the "little fogger". Reservoir 102 contains an RFID tag (see FIG. 1B) with a non-volatile memory (e.g., flash memory or EEPROM), containing a field (e.g., one byte or two bytes in size) containing a value corresponding to with the amount of hydrogen peroxide that is (still) present in the reservoir 102.

The nebulizer 100 has a control unit 215, (also referred to herein as "controller"), e.g., a programmable processor, and an RFID reader-writer 204 connected to this processor, (not visible in FIG. 1A, but see FIG. 2) , so that the control unit can read data stored in the RFID tag, e.g. the initial amount of hydrogen peroxide mixture, but optionally also other data such as e.g. one or more values selected from the group consisting of: the production date of the hydrogen peroxide mixture, a cut-off expiration date, the concentration of hydrogen peroxide in the (liquid) hydrogen peroxide mixture.

According to an important aspect of the present invention, the fogging device 100 is provided to keep the value of this field in the RFID tag (corresponding to the amount of liquid mixture) up-to-date, e.g. , e.g. periodically updated when the first pump 205 is active, i.e. when liquid is being drawn from the reservoir 202. Preferably, this field is updated at least once every 20 seconds that the first pump 205 is active, e.g. at least once every 10 seconds that the first pump is active, or at least once every 8 seconds, or at least once every 6 seconds, or at least once every 5 seconds, or at least once every 4 seconds. The more often this value is updated, the more closely the content of the field corresponds to the actual amount of fluid in the reservoir. By updating the field repeatedly (as opposed to just once at the end of a disinfection cycle}, it can be assumed that this field correctly reflects the actual contents of the tank, even if the disinfection cycle was interrupted prematurely by e.g. a power cut.

FIG. 1B shows the container containing the hydrogen peroxide mixture 102 of FIG. 1A, and with a

RFID tag 103. The RFID tag is also enlarged with increased contrast.

FIG.2 shows a block diagram of a possible embodiment of the nebulizer device of FIG. 1A.

As already mentioned above, the nebulizing device 200 includes a first fluid circuit with a first inlet "IN1" for receiving a first gas stream from the room to be disinfected in which the device is located, and with means to dispense small droplets (e.g., with an average diameter of 10 to 50 microns, e.g. from 20 to 40 microns) of a hydrogen peroxide mixture to be added to this first gas stream, and with a first outlet "OUT1" for supplying this first gas stream with these droplets to the chamber, and with a first pump 205 for circulating air through the first fluid circuit.

While it is technically possible to provide a fluid pump to pump fluid from the reservoir and add it to the first stream of air, the nebulizer 200 preferably does not include a fluid pump, but fluid is added from the reservoir through a tube or hose 206 that is introduced into the reservoir 202, along which liquid is drawn in by means of the Venturi principle, caused by the velocity of the first gas stream. Preferably, the first pump 205 has a predetermined (non-adjustable) speed. The first pump 205 and the diameter of the pipes of the first fluid circuit can be dimensioned such that the velocity of this air stream is, for example, 40 m/s to 80 m/s, or a value in the range of 50 m/s to 70 m/s. m/s, e.g. approximately equal to 60 m/s. This allows the liquid mixture to be sucked out of the reservoir at a flow rate of about 30 to 60 ml/min, as will be further explained in FIG. 6.

The nebulizer 200 further includes a control unit 215, also referred to as a controller, e.g., a programmable microprocessor, as well as working memory (RAM) and non-volatile memory (e.g., flash memory or EEPROM or the like), located internally or externally of the processor. can be located. The non-volatile memory preferably contains a computer program that contains instructions that can be executed by the controller 215. Preferably, this computer program executes a method 1000, as described in FIG. 10 to FIG. 13. This computer program is provided, among other things, for controlling the first pump 205, e.g. to switch the pump ON or OFF, e.g. by means of a relay. Such circuits are well known and therefore need not be described in detail.

The nebulizer 200 further includes provision for connecting to the first circuit a replaceable reservoir 202 containing a hydrogen peroxide mixture, e.g. via a screw cap connector and a tubing 206. The reservoir 202 carries an RFID tag 103 with a non-volatile memory in which data is stored. stored. This data contains at least the amount of the hydrogen peroxide mixture, e.g. in the case of the tank 102 for the "small fogger" the initial amount is approximately equal to 1000 ml, in the case of the tank 302 for the "large fogger" the initial amount approximately equal to 3000 ml.

The nebulization device 200 further includes an RFID reader-writer 204, which is positioned in proximity to the container's RFID tag when the container is connected to the nebulization device. The RFID reader-writer 204 has an antenna (not explicitly shown in FIG. 2) that allows it to communicate wirelessly with the reservoir's RFID tag. The RFID reader-writer is communicatively connected to the control unit 215 so that the control unit 215 can read and/or write data from the RFID tag.

In accordance with an important aspect of the present invention, the

Reservoir RFID tag written when the first pump 205 is active to keep the amount of hydrogen peroxide mixture up to date. Preferably, the memory field containing the initial amount of hydrogen peroxide mixture is repeatedly overwritten, but the present invention is not limited thereto, and it is also possible to provide multiple fields to be written or overwritten sequentially.

The nebulizer 200 further includes a user interface, e.g., a display, (e.g., a

LCD screen) and keys, or a touchscreen 212, or the like, communicatively connected to the control unit 215. In this way, the control unit can exchange information with the user, e.g. request data, and/or display data.

Further, the nebulizer 200 includes a timing circuit 217, e.g., a timer and/or a real-time clock. "Real-time clock" refers to a chip or module, optionally with a battery, that keeps track of not only the time, but also the date. However, the latter is not strictly necessary, and it is sufficient that the control unit 215 can measure the time.

Preferably, the nebulizer 200 also includes a buzzer 213, or a loudspeaker or the like, capable of generating an acoustic signal. In this way, the control unit can, for example, indicate that an operator must leave the room and/or may not enter the room yet. In this way the safety of the operator can be increased.

Optionally, the nebulizer 200 also includes an RF communication module 211, e.g. a

Bluetooth module or a Wifi module, to communicate with one or more external devices, e.g. with a remote control. This aspect will be further explained in FIG. 4 and FIG. 5, but is not strictly necessary for the operation of the nebulizer.

This completes the main hardware components of the nebulizer 100 of

FIG. 1A, which can be seen as a "minimum design", but of course the present invention is not limited thereto and one or more components can be added, e.g. internal to the nebulizer, or external to the nebulizer, or both , as will be described further (e.g., in FIG. 4 and FIG. 5).

In FIG. 10 to FIG. 13 will describe a method that can be performed by the nebulizer 200 to disinfect a room, in "open-loop" (without hydrogen peroxide sensor), or in "closed-loop" (English: closed loop, with hydrogen peroxide sensor), but before explaining such a method, a second embodiment of an atomizing device will first be described with reference to Figures 3A to Figure 5. For now, it suffices to know that an operator can enter certain parameters (e.g. temperature and relative humidity and volume) of the room to be disinfected via the user interface, and that the controller 215 can check via the RFID tag how much hydrogen peroxide mixture is actually available in the reservoir 202, and that the controller 215 can check (and display) if the available amount of hydrogen peroxide mixture is sufficient to adequately disinfect the room (and optionally if the best before date has not yet passed) If the user decides to continue, a disinfection cycle can be started, after which the controller 215 will usually generate an audible signal to indicate that the operator should leave the room, after which the controller 215 will control the first pump 205 to run a disinfection cycle, e.g. based solely on time information. If a hydrogen peroxide sensor is present, this can be used, and a "closed-loop" disinfection cycle can be completed. This will be further explained in more detail with reference to FIG.6 to FIG. 15B.

FIG. 3A shows a second example of a fogging device 300 according to an embodiment of the present invention, also referred to herein as a "large fogger", in perspective view. This device can be viewed as a variant of the fogging device of the present invention.

FIG. 1A, and aside from the differences, what was described above for the "small fogger" also applies here, mutatis mutandis.

The fogging device 300 (the "large fogger") is larger and heavier than the fogging device 100 (the "small fogger") of FIG. 1A, and the chassis therefore preferably includes four wheels 331, 332 and a handle 334 for moving the device. In the example shown, for practical reasons the device comprises two non-swivelling wheels 331 located on the side of the handle, and two swiveling wheels 332 with wheel brake 333 on the opposite side, but this is of course not essential for the invention. In the example of FIG. 3A, the non-swivel wheels 331 have a larger diameter than the swivel wheels 332, but again this is not essential, and the invention will work even if the apparatus had four similar wheels, swivel or non-swivel, with or without wheel brake.

The nebulizer 300 further comprises a user interface 312, in the example in the form of an LCD touchscreen (touch screen), where information can be displayed to the operator, and where the operator can enter certain values (e.g. room temperature, relative humidity of the room , volume of the room), and/or can select or set certain parameters, and/or can start the disinfection process, etc. Instead of a touch screen 312, an ordinary display can of course also be used (e.g. LCD screen without input option) and one or more pushbuttons and/or rotary knobs or the like.

It should be noted that the nebulizer device 300 preferably has a communication module 411, e.g., an RF communication module (e.g., Bluetooth or Wifi). This is not visible in FIG. 3A, but is shown in FIG. 4 and FIG. 5, which means that the presence of a user interface 312, 412 on the nebulizer 300 itself is not strictly necessary, since communication with the operator could also take place via an external device, e.g. a remote control or a laptop or a smartphone. But the presence of a user interface on the device itself is useful, and allows the nebulizer to work stand-alone (by itself), without external devices.

Within the nebulizer 300, space is provided for two reservoirs 4024, 402b, each containing 3 liters of hydrogen peroxide mixture. To connect a new reservoir and/or replace an existing reservoir, an operator must open the top cover 336 by means of a lever or handle 337. Alternative embodiments may accommodate more than two reservoirs of hydrogen peroxide mixture, e.g., three or four reservoirs, or two reservoirs with a capacity greater or less than 3 litres. Each container has an RFID tag 303 with data including a field displaying the amount of hydrogen peroxide in the respective container. The nebulizer 300 of FIG. 3A includes two RFID reader-writers 4044, 404b, each provided to communicate with one RFID tag. The antennas of the RFID reader-writers are dimensioned (relatively small) in such a way that they can only communicate with the reservoir over a relatively short distance, and in such a way that communication with another reservoir that does not belong to the RFID reader-writer in question , is avoided. It is of course also possible to provide an electromagnetic shielding, but this is not strictly necessary.

As explained above for the "small fogger", the fogging device 300 includes a controller 415, e.g., a programmable microcontroller, provided with a software program that contains routines to update the value of the amount of liquid mixture in each reservoir, on each RFID tag. to date, and updated repeatedly as fluid is drawn from a reservoir.

Visible in FIG. 3A are also two nozzles 301, which form the outlet OUT1 of the first fluid channel, along which the air with droplets of hydrogen peroxide mixture are blown into the chamber. Also visible in FIG. 3A are two openings IN2 of the second fluid channel. Unlike the "little fogger" of FIG. 1A has the "large fogger" of FIG. 3A namely an active filter for removing hydrogen peroxide from the chamber during a third phase of the atomization process. This active filter may include an active carbon filter, or may include a metal catalyst, or both. The output OUT2 of the second fluid channel is not visible in FIG. 3A, but located at the bottom of the device.

FIG. 3B shows an example of a reservoir 302 that may be used in conjunction with the nebulizer 300 of FIG. 3A. The reservoir of FIG. 3B can hold 3000 ml hydrogen peroxide mixture, but of course the invention will also work with larger or smaller reservoirs.

Certain tests (with a relatively narrow range of room volume, temperature and relative humidity) have shown that under certain conditions about 7 to 10 ml of mixture per cubic meter of room volume of silver stabilized hydrogen peroxide mixture with a hydrogen peroxide concentration in the liquid mixture of 12.5% by weight, was sufficient to obtain a disinfection that complies with the EN17272 standard. That amount is sufficient to create a gas phase hydrogen peroxide concentration of about 100 to about 120 ppm in the chamber. This quantity can be calculated using the following formula:

NH=KV*A where NH is the required amount of hydrogen peroxide mixture (expressed in ml), and where KV is the volume of the chamber (expressed in cubic meters), and where A is a predetermined value (expressed in ml/m3).

In one embodiment, the value of A is a number in the range of 7 to 10 ml/m³, but the invention is not limited thereto, and values of A in the range of 5 to 25 ml/m³, or in the range of 5 to 20 ml/m°, or in the range of 5 to 15 ml/m3, or in the range of 8 to 25 ml/m°, or in the range of 8 to 20 ml/m³, or in the range of 8 to 15 mi/m2 are also possible. Optionally, this value is adjustable by the operator.

Optionally, the RFID tag contains not only the amount of hydrogen peroxide mixture in the reservoir, but also the value of the hydrogen peroxide concentration in the liquid mixture, and the nebulizer is provided to request (read) this value from the RFID tag, and to take this into account when determining the amount of hydrogen peroxide mixture to be introduced into the chamber.

Preferably, before actually starting the cycle, the device will first check whether there is sufficient hydrogen peroxide mixture present in the two reservoirs together, and will give an error message if there is not enough hydrogen peroxide mixture present. This will be discussed further in the method of FIG. 10 to FIG. 13.

Preferably, the device will also request the temperature and relative humidity of the room from the operator, or measure it itself (if it contains the necessary sensors, or if it has contact with external sensors), and the device will also check whether the target hydrogen peroxide concentration is achievable based on the given room conditions, and will generate an error message if the target concentration is not achievable. This will be further discussed in FIG. 9A and FIG. 9B.

As an illustrative example, but the invention is not limited thereto, a nebulizer according to the present invention with a full reservoir of 1 liter (1000 ml) of silver stabilized hydrogen peroxide mixture having a hydrogen peroxide concentration of 12.5% by weight, can fill a room or room of about 100 m3 disinfection by during a first phase (see

FIG. 14B) to introduce about 450 ml of mixture into the chamber over about 8 or 9 minutes, raising the hydrogen peroxide concentration in the chamber to about 100 to 120 ppm, and then, during a second phase of about 60 minutes, the remaining 550 ml of the mixture into the chamber, by "intermittently fogging" with an appropriate duty cycle, so that a total contact time of approximately 60 minutes is achieved. The total time of phase1 and phase2 is therefore approximately 68 to 69 minutes in this example.

As an illustrative example, but the invention is not limited thereto, a nebulizer according to the present invention with one full 3 liter (1000 ml) reservoir of silver stabilized hydrogen peroxide mixture having a hydrogen peroxide concentration of 12.5% by weight, a room or area of approximately 300 m ° disinfecting during a first phase (see

FIG. 14B) introduce about 1350 ml of mixture into the chamber from about 24 to 27 minutes, raising the hydrogen peroxide concentration in the chamber to about 100 to 120 ppm, and then, during a second phase of about 60 minutes, an additional 1650 ml of the mixture (e.g. from the same reservoir, and/or from the other reservoir) into the chamber, by "intermittently fogging" with an appropriate duty cycle, so that a total contact time of approximately 60 minutes is obtained, so the total time of phase 1 and phase 2 in this example is approximately 84 to 87 minutes.

These are of course only examples, and since the large fogger has two reservoirs of 3 liters each, it can also be used to disinfect a room larger than 300 m3.

FIG. 3C shows one side (designated by the letter "X") of the reservoir of FIG. 3B on which a

RFID tag 303 is applied. The RFID tag is also enlarged with increased contrast.

FIG. 4 shows a block diagram of one possible embodiment of the nebulizer 300 of FIG. 3A. This block diagram (of the "big fogger") is a variant of the block diagram of FIG. 2 (of the "little fogger"). The basic function of the "large fogger" 300 is the same as that of the "small fogger" 100, which is to disinfect a room, but there are a number of differences, including: (i) this fogging device accommodates two reservoirs 4024, 402b with hydrogen peroxide mixture, and optionally also to a third tank 420 with sterilized water, for optional rinsing of the device after stage 1 and stage 2, to purge the lines; (ii) that each reservoir can be individually and selectively connected to or disconnected from the nozzle by means of an associated valve V1, V2, V3. These valves are controlled (e.g., opened or closed) by the controller 415; (iii) that the valves V1, V2, V3 are connected to a common pipe leading to the nozzle 401, in the example via a manifold 422; (iv) that this dispensing device comprises two RFID reader-writers 404a, 404b, one for each container with an RFID tag, and with a hydrogen peroxide mixture;

(v) that this atomizing device further has means for actively removing hydrogen peroxide from the ambient air, in the example a scrubber 421 with an active carbon filter. The scrubber 421 is part of a second fluid circuit with a second inlet

IN2 and a second outlet OUT2, and has a second pump "PUMP2" for circulating a stream of air through the second fluid circuit. This second pump can be selectively switched ON or OFF by the controller 415, e.g. during a third phase F3 of the disinfection process (see

FIG. 14A to FIG. 14C).

In an alternative embodiment, the active carbon filter is replaced by a catalyst to hydrogen peroxide H2O; to remove from the room. It is also possible to use both an active carbon filter and a catalyst.

These differences allow the fogging device 300 ("the big fogger") to disinfect a larger room, and the third stage F3 will take less time, so that the room can be cleared more quickly. It also offers the advantage that (for rooms smaller than about 300 m3) it can use the hydrogen peroxide mixture more economically, because it can first empty one reservoir before starting a new reservoir. With this device it is therefore not necessary to always start a new cycle with new reservoirs, and it can also be avoided that liquid has to be poured over, which benefits the safety of the operator.

Although not strictly necessary to perform a disinfection cycle with high reliability, the fogging device 300 preferably includes an RF communication module, e.g. with

Bluetooth and/or with Wifi, and the nebulizer device is provided to communicate with a "remote control" 540 (see FIG.5). This remote control can be an existing tablet or a smartphone, with an appropriate application (app), and can optionally have a touch screen (touch screen) In a simple implementation, the remote control application may be provided to remotely start the nebulizer, e.g., after an operator enters the necessary data through the touch screen 412 on the nebulizer itself device remotely, and the controller 415 will start or stop the device accordingly as if the user had given this command through the touch screen 412. However, the present invention is not limited thereto and it is also possible to run a more extensive application on the remote control. which is provided to display the same information as appears on the display 412 of the nebulizer device 400, and to display input data (e.g., temperature of the room, volume of the room, relative humidity of the room), entered on the remote control, to be sent to the controller 415. The controller 415 in this case will be arranged to process either commands or data entered through the local user interface 412, or via remote control 540. The major advantage of using a remote control is that it allows an operator to operate the nebulizer device remotely, and/or monitor its status, e.g. while outside the room . After all, it is very dangerous to enter the room without personal protective equipment such as a respirator, as long as the gaseous hydrogen peroxide concentration in the room exceeds a predetermined safe value, typically 1.0 ppm. The development and/or manufacture of such remote control 540 (hardware and/or software) is known in the art, and thus needs no further explanation.

For the sake of completeness, it is noted that, in a practical implementation of the block diagram of FIG. 4 the "first fluid channel" can be implemented e.g. as two physical channels in parallel, each with its own entrance, its own pump, and its own nozzle, but this is not essential, and such details therefore need not be explained further .

FIG. 5 shows a fogging system 590 that includes a fogging device 500 in accordance with an embodiment of the present invention (e.g., a "small fogger" as shown in Fig.

FIG. 1A or a "large fogger" as shown in FIG. 3A), and one or more external devices selected from: one or more hydrogen peroxide sensors 531 for measuring a hydrogen peroxide concentration in gas phase, at one or more locations in the chamber. If present, these hydrogen peroxide sensors can be used, e.g., in steps 1021 to 1023 of the method of FIG. 13, corresponding to stage 3 of FIG. 14A to FIG. 14C, specifically to perform a "closed loop" process; - one or more temperature sensors 532 for measuring an ambient temperature at one or more locations in the room. If present, they can be used e.g. in step 1011 or 1012 of the method of FIG. 11; - one or more relative humidity sensors 533 for measuring a relative humidity at one or more locations in the room. If present, they can be used e.g. in step 1011 or 1012 of the method of FIG. 11; - one or more fans or ventilators 551 for distributing the air with droplets in the chamber, and thus to make the hydrogen peroxide concentration in the chamber more even. If present, these fans can be used e.g. in steps 1021 to 1023 of the method of FIG. 13, - one or more air heaters 552 for heating the air in the room to condition the room. If present, these air heaters can be used e.g. in step 1011 of the method of FIG. 11; one or more dehumidifiers 553 to lower the relative humidity of the air in the room by extracting water vapor from the air to condition the room.

If present, these dehumidifiers can be used e.g. in step 1011 of the method of FIG. 11;

- one or more external scrubbers 554 to reduce the gaseous hydrogen peroxide concentration present in the air of the chamber. If present, these scrubbers can be used e.g. in step 1023 of the method of FIG. 13, corresponding to stage 3 of FIG. 14A to FIG. 14C, to further reduce the duration of the third stage, thus further accelerating the overall decontamination process, so that the chamber can be cleared more quickly, but without sacrificing the fidelity of kill. - a remote control 540. This has already been discussed above. - a laptop 541 or a tablet or a smartphone or the like. This can perform the function of the remote control 540, and possibly even more, such as e.g. parameters or settings, or even adjust the entire software program of the nebulizer.

Preferably, any of these external devices, if any, can be communicatively connected to the control unit 415 of the nebulizer device, e.g. via the RF communication module, or optionally via a cable connection (not shown), e.g. RS232, USB, etc.

The hydrogen peroxide sensor 531, and the temperature sensor 532 and the relative humidity sensor 533 may possibly be integrated in one sensor device 530. This sensor device 530 may further comprise a controller 539 for controlling and/or reading the sensors, and may comprise a port (not shown ) for connecting a cable (e.g. RS232,

USB, etc.), and/or may include an RF communication module 538 to transmit data wirelessly.

In a specific embodiment, the nebulizer system 590 includes the nebulizer 500 with two hydrogen peroxide reservoirs 4024, 402b and with a third reservoir 420 of sterilized water (to flush the lines), and a laptop 541 with both

Bluetooth as WiFi utilities, and an external sensor device 530 comprising at least a hydrogen peroxide sensor 531, an RF communication module 538 with Bluetooth, and a controller 539. In such a system, the controller 515 of the nebulizer device can communicate with the controller 539 of the sensor device 530 via the laptop, which acts as a gateway. In such an arrangement, the laptop can also be used to log data to a local storage medium 542 (e.g. hard disk), or to a network drive (not shown}, or to the cloud 543 or the like.

In another or further embodiment, the fogging system 590 includes the air heater 552 and the dehumidifier 553, which are preferably automatically controlled by the controller 515 of the fogging device 500, e.g. via a cable (not shown), or via a wireless connection (e.g. .Bluetooth or Wi-Fi) . These devices 552, 553 allow the room to be conditioned if the temperature and/or the humidity do not meet the necessary conditions to atomize the intended amount of hydrogen peroxide (e.g. about 100 to 120 ppm) in the room.

In another or further embodiment, the atomization system 590 includes at least two hydrogen peroxide sensors 531, preferably located at different locations in the chamber; and the nebulizer 500 is arranged to receive a value from each of these at least two hydrogen peroxide sensors, and to generate a minimum of of this multiplicity of values as the relevant gas phase hydrogen peroxide concentration in the chamber (e.g. by ensuring that the minimum value is at least 100 ppm), and during the third stage (stage3) of the disinfection cycle (see FIG. 14A to Fig. 14C) consider a maximum of this plurality of values as the relevant gas phase hydrogen peroxide concentration in the chamber (e.g. by causing the maximum value to fall below 1.0 ppm). In this way, on the one hand, the probability is increased that the hydrogen peroxide concentration everywhere in the room contains at least the predetermined value (e.g. about 100 ppm), in order to achieve sufficient killing everywhere in the room (e.g. according to standard EN17272), and on the other hand to reduce the risk to ensure that the hydrogen peroxide concentration somewhere in the room exceeds the predetermined safe value (e.g. 1.0 ppm) before releasing the room again.

Of course, many other combinations are possible of the nebulizer 500 with one or more of the aforementioned external devices, shown in dotted line in FIG. 5.

For the sake of completeness, it is noted that it is also possible to build one or more of these devices, e.g. a first, internal scrubber), as well as an external device (e.g., a second scrubber).

FIG. 6 shows an exemplary curve illustrating the flow rate of the liquid hydrogen peroxide mixture from the reservoir as a function of the degree of filling of the reservoir, as applicable in atomizing devices according to the present invention that utilize the venturi effect. This curve is mainly determined by the speed of the airflow in the first fluid channel, as well as by the shape and size of the nozzle.

As can be seen, the relationship between the liquid flow rate (of the hydrogen peroxide mixture) and the amount of liquid in the reservoir is almost linear. This graph was measured for a 3000 ml reservoir with a height of approximately 25 cm, measured in a prototype "large fogger" of FIG. 3A. In the specific example of FIG. 6, the fluid flow rate can be calculated or approximated from the following formula:

VD [ml/min] = 30.8 [ml/min] + 0.31*VG [in %] [1]

where VD is the fluid flow rate (expressed in ml/min), and

VG is the filling level of the reservoir (expressed in %), but of course this may be different for another nebulizer device.

So in the example of FIG. 6, the fluid flow rate is approximately 30.8 + 31.0 = 61.8 ml/min for a full reservoir (VG=100%), and the fluid flow rate is approximately 30.8 + 0.31 = 31.1 ml/min for an almost empty reservoir (VG=1%). That is almost a factor of two difference between a full reservoir and an almost empty reservoir. It will be appreciated that this must be taken into account in order to introduce and/or maintain an accurate concentration of hydrogen peroxide in the chamber (e.g. during the second phase of FIG. 14A to FIG. 14C). This will be further discussed in FIG. 15A and FIG. 15B.

The liquid flow rate in a prototype "small fogger" of FIG. 1A is similar, but the measurement points are slightly shifted. For the sake of completeness, it is noted that the e specific curve of FIG. 6 was measured in an 81 m3 test chamber.

FIG. 7 shows another representation of the curve of FIG. 6, showing fluid flow rate as a function of cumulative time, starting from a full 3000 ml reservoir. This graph can be derived from the graph of FIG. 6, or based on formula [1], using the following formulas:

AVfluid [in ml] = VD [in ml/min] * AT [in min] [2] where AVfluid is the volume of fluid drawn from the reservoir for a short time AT, VD is the fluid flow rate mentioned above (expressed in ml/ min), and AT the time span (expressed in minutes). It should be noted that this graph is not linear.

In the example of FIG. 7, AT was chosen as a period of 10 seconds, and every 10 seconds the amount of liquid remaining in the reservoir was calculated, as well as the corresponding liquid flow rate. These values can be calculated iteratively, or can be stored in a table. If AT = 10 seconds, then a table of approximately 408 items is sufficient. Such a table can easily be stored in a non-volatile memory of the device. But of course the invention is not limited to this, and it is also possible to store other tables, or to store the curve in a different way, e.g. by storing the coordinates of a stepwise linear approximation. piecewise linear approximation").

FIG. 8 shows a curve 891 representing the contents of a 3000 ml reservoir as a function of the cumulative time fluid is drawn from the reservoir (i.e., the cumulative time the first pump is ON), corresponding to the fluid flow rate of FIG. 6 and FIG. 7. The curve 891 is clearly non-linear (it lies below the dotted line). The area under the curve 891 also illustrates that it takes e.g. much less time (in the example 500 seconds versus 790 seconds)

to withdraw 500 ml of liquid mixture from a full reservoir (e.g. with a capacity of 3000 ml to 2500 ml) compared to a reservoir that is almost empty (e.g. with a capacity of 1000 ml to 500 ml).

In practice, a lot of hydrogen peroxide mixture would be wasted if one had to start from a completely filled reservoir each time. In order to allow the nebulizer to operate with a container that is not completely filled, a correct knowledge of the content of the hydrogen peroxide mixture still present in the container is therefore necessary in order to make a good estimate of the time required to reach a certain quantity of mixture from the reservoir (in the example: 500 ml, but this is only an example). This is especially important for an "open-loop" method, i.e. one in which the gaseous hydrogen peroxide concentration in the chamber is not measured effectively (e.g. because no hydrogen peroxide sensor is present), but estimated over time, and usage making the above table, or mathematical formulas and iterative calculations, established on the basis of the results of various tests with varying values of temperature, humidity and room size, in which the gaseous hydrogen peroxide concentration in the room was measured in a test set-up.

During the experiments, the inventors also found that the gaseous hydrogen peroxide concentration in the chamber cannot be increased indefinitely, but that it is limited to a ceiling value. They also found that this ceiling value mainly depends on temperature and relative humidity in the room. Further research has led to the graph of

FIG. 9A.

FIG. 9A shows three curves representing the maximum gaseous hydrogen peroxide concentration that can be achieved by so-called "cold fogging" (i.e., nebulizing without heating the liquid mixture), as a function of ambient temperature (T) and relative humidity (RH) in a room. These curves apply to a hydrogen peroxide mixture with a liquid phase hydrogen peroxide concentration of approximately 12.5% by weight in demineralized water.

In general, it can be said that the higher the temperature and the lower the relative humidity of the room to be disinfected, the higher the maximum hydrogen peroxide concentration achievable with this mixture.

In preferred embodiments of the present invention, the target gas phase hydrogen peroxide concentration is about 100 ppm. As seen in FIG. 9A, this value is achievable in: - a room with relative humidity = 49% and temperature of at least 15°C, - a room with relative humidity = 60% and temperature of at least 19°C, - a room with relative humidity = 70% and Temperature of at least 21.5°C, etc,

If the temperature and relative humidity of the room meet one of these conditions, then it does not need to be "conditioned", i.e. the temperature does not have to be raised, and/or the relative humidity has to be lowered before a disinfection cycle can be started. be started (this means e.g. that step 1011 of FIG. 11 can be skipped). The specific curves of FIG. 9A were measured in the 81 m° test chamber mentioned above.

FIG. 9B shows a curve derived from FIG. 9A, and which represents the minimum room temperature as a function of the relative humidity, or vice versa, which indicates the maximum relative humidity for a given temperature, in order to achieve a gaseous hydrogen peroxide concentration of 100 ppm in the room by “cold fogging” of a hydrogen peroxide mixture containing substantially 87.5 wt% demineralized water and substantially 12.5 wt% hydrogen peroxide, and preferably also 0.006 to 0.008 wt% silver ions. Such hydrogen peroxide mixture is commercially available from Roam Technologies under the product name: " Huwa-San TR-12.5".

Using the curve of FIG. For example, 9B, the nebulizer may determine that a target gaseous hydrogen peroxide concentration of e.g. 100 ppm by nebulizing "Huwa-San TR-12.5" is not achievable if the relative humidity is 80%, and the temperature in the room is lower is then 23.5°C. Such a test can be performed e.g. in step 1020 of FIG. 10 or FIG. 12.

FIG. 10 shows a flowchart of a method 1000 that can be performed by an atomization device as illustrated in FIG. 1 to FIG. 4, and/or by an atomization system 590 as illustrated in FIG. 5, with one or more external devices. Different variants of the method are possible, depending on which facilities are available, e.g.: - If the fogging device 100, 200, 300, 400, 500 contains a temperature sensor and/or a humidity sensor, or has communicative access to an external temperature sensor 532 and/or or an external humidity sensor 533, the device can itself measure the temperature and relative humidity of the room to be disinfected. Alternatively, the operator can measure the temperature and/or relative humidity, and enter the values through the display 412 of the device or through the remote control 540 (if present), before starting a disinfection cycle. - If the nebulizing device 100, 200, 300, 400, 500 has an air heater and/or an air dehumidifier, or has communicative access to an external air heater 552 and/or an external air dehumidifier 553, then the fogging device can optionally increase the temperature in the room , and/or lower the relative humidity in the room. Alternatively, if an external air heater 552 and/or a dehumidifier 553 are present in the room, but not communicatively connected to the fogging device, an operator can optionally operate these devices manually before starting a disinfection cycle. But as explained above (cf

FIG. 9A and FIG. 9B), the presence of an air heater and/or a dehumidifier is not strictly necessary, and it is often possible to start a disinfection cycle without preconditioning the room, if the temperature and relative humidity meet the conditions e.g. shown in FIG. . 9B. - If the nebulizer 100, 200, 300, 400, 500 contains a hydrogen peroxide sensor internally, and/or has communicative access to an external hydrogen peroxide sensor 531, then the nebulizer can measure the gas phase hydrogen peroxide concentration in the chamber, and the process parameters (e.g. duration of phasel of Fig. 14C, starting and stopping the so-called intermittent fogging during phase2, and releasing the room after phase3), adjusting dynamically, taking into account the measured values, in a so-called "closed-loop" management. If the nebulizer does not have access to a hydrogen peroxide sensor, the nebulizer can perform an atomization process in so-called "open-loop" control, based on time, taking into account the current filling level of the reservoir(s).

The method 1000 of FIG. 10 as proposed by the present invention actually comprises four major steps: i) collecting 1010 data for performing an atomization process in a particular chamber; ii) checking 1020 whether the collected data meets certain conditions in order to be able to successfully carry out the intended atomization process, and if not all conditions are met, giving 1030 an error message, and if all conditions are met, proceeding to step 1040 ; iii) performing 1040 the atomization process; iv) reporting 1050 whether or not the nebulisation process has been carried out successfully, e.g. by verifying whether a power failure occurred while the disinfection process was active, or e.g. in case of “closed loop” control, by verifying whether an abnormal amount of hydrogen peroxide mixture had to be atomized to reach the target concentration in gas phase (e.g. 100 ppm) Such an abnormally high value could be the result, for example, of an open window.

FIG. 11 shows a possible refinement of the first major step i) of FIG. 10, regarding the collection of data from the chamber, and may include one or more of the following steps: b) determining 1012 conditions of the chamber, including the temperature and relative humidity of ambient air in the chamber to be disinfected. As described above, this step may include an automatic reading of appropriate sensors, if built into the nebulizer device, or external to it, but communicatively connected to it. Alternatively, this step may include, e.g., receiving data input on the user interface 212, 412 of the nebulizer device. If the room was conditioned by means of an air heater and/or a dehumidifier, in step 1011, step 1012 can be skipped; c) determining 1013 the volume of the room to be disinfected (e.g. the number of cubic meters). This step may include, e.g., receiving the appropriate value via the nebulizer device user interface 212, 412, or may include, e.g., receiving a length, width, and height of the chamber, after which the nebulizer device will calculate the volume of the chamber. calculates. Optionally, this volume can be stored in a non-volatile memory of the device, e.g. together with a "name" (e.g. a character string) of the room in question, so that it can be retrieved later. d) determining 1014 the hydrogen peroxide concentration of the liquid mixture in the reservoir. For example, this step may include receiving the appropriate value via the user interface 212, 412 of the nebulizer device, or may include the controller 215, 415 automatically reading the appropriate value from the RFID tag by the controller 215, 415 (if the RFID tag allows this). value); e) estimating 1015 the amount of hydrogen peroxide mixture required to introduce a predetermined concentration (e.g. 100 ppm) of gas phase hydrogen peroxide into the chamber during a first phase (phase 1) and to maintain this concentration for a predetermined contact time ( e.g. tabout 60 min) during a second phase (phase2). These predetermined values (e.g. the concentration of 100 ppm, and the contact time of 60 minutes) can be predetermined in the software of the nebulizer device, or can optionally be set or adjusted by the operator via the user interface 212, 412;

The amount of hydrogen peroxide mixture required to increase the predetermined concentration of hydrogen peroxide in gas phase (during a first phase) and to maintain it for a certain "contact time" (during a second phase), can be determined e.g. on the basis of the following formula: NH = KV * A where NH is the required amount of hydrogen peroxide mixture (expressed in ml), and where KV is the volume of the chamber (expressed in cubic meters), and where A is a predetermined value (expressed in ml/m?). The value A depends on the concentration of hydrogen peroxide in the hydrogen peroxide mixture, and possibly also on the room conditions (e.g. temperature and relative humidity), and possibly also on the room volume. This can be represented mathematically by the following formulas:

A = f1(H202 concentration in the hydrogen peroxide mixture), or:

A = f2(H202 concentration in the hydrogen peroxide mixture, Tchamber, RVchamber), or:

A = f3(H202 concentration in the hydrogen peroxide mixture, Tchamber, RVchamber, Vchamber), where Tchamber, RVchamber and Vchamber are respectively the (initial) temperature, relative humidity and volume of the chamber before the start of the disinfection process. For example, one or more of these functions may be stored in tabular form in a non-volatile memory 216, 416 of the nebulizer device, but the present invention is not limited thereto, and the process parameters may also be queried from a network application running in the cloud, after forwarding the parameters mentioned above.

As an example, for a chamber volume of about 50 m3, and using a silver stabilized hydrogen peroxide mixture with a hydrogen peroxide concentration of 12.5 wt%, and an (initial) room temperature of about 20°C and a relative humidity of about 65%, A is preferably a value in the range of 7 to 10 ml/m 3 .

NH thus represents the total amount of hydrogen peroxide mixture to be atomized during the first and second phase. The ratio of the amount of hydrogen peroxide mixture to be nebulized during the first phase and the second phase can be a value of about 45%, or a value in the range of 40% to 50%, or a value in the range of 35% to 55%, or a value in the range of 30% to 60%. In one embodiment this ratio is a constant value, e.g. 45%, but the invention is not limited thereto, and in other embodiments this ratio may be a function of one or more of the following parameters: the hydrogen peroxide concentration in the hydrogen peroxide mixture, Troom, RVroom, Vroom, where Troom, RVroom and Vroom are the (initial) temperature, relative humidity and volume of the room before the start of the disinfection process, respectively. f) determining 1016 how much hydrogen peroxide mixture is available in the at least one reservoir. This step may include, for example, reading the relevant value from the RFID tag(s). If several reservoirs are connected, the quantities must be added up.

FIG. 12 shows a possible refinement of the second major step ii) of FIG. 10, regarding the verification that the collected data meet certain conditions to successfully carry out the atomization process, and may include one or more of the following steps: achieve gas phase hydrogen peroxide concentration in the chamber; and j) verifying that the temperature and relative humidity of the chamber meet a predetermined criterion (e.g., as shown in FIG. 9B) to achieve the target gas phase concentration; and k) checking whether the available amount of hydrogen peroxide mixture in the at least one reservoir is greater than the required amount of mixture.

As shown in FIG. 10, if all conditions are met, the nebulization device can continue to perform 1040 the nebulization process, (possibly after a certain waiting time during which an audible signal is produced so that the operator can leave the room); and if not all conditions are met, giving 1030 an error message.

In another or further embodiment, the RFID tag 103, 303 on the at least one container also includes an expiration date of the hydrogen peroxide mixture, and the control unit 215, 415 is further provided to determine a current date, (e.g. by reading a real-time clock 417 in the device, or request the current date from an external device, e.g. from a laptop communicatively connected to it, or retrieve it from the Internet), and the control unit (as an additional test) ) even after the expiry date (i.e. beyond the current date). If the use-by date has passed, an error message can be given in step 1030. If the use-by date has not yet passed, the control unit can proceed to step 1040.

FIG. 13 shows a possible refinement of the third major step iii), which involves performing the atomization process, and may include one or more of the following steps: m) adding air containing droplets of the hydrogen peroxide mixture to the chamber (herein referred to as "fogging" mentioned), for increasing the gas phase hydrogen peroxide concentration in the chamber, and repeatedly updating the RFID tag 103, 303 to keep the value of the amount of hydrogen peroxide mixture in each reservoir up-to-date. This step m) corresponds to a first phase "phase!" of the atomization process (see FIG. 14A to FIG. 14C). * This increase can be done in "open loop control", e.g. if no hydrogen peroxide sensor is present, in which case the (predicted) increase of the gas phase hydrogen peroxide in the chamber is based on the time the first pump was active, and taking into account the variable flow rate; * This increase can also be done in "closed loop control", e.g. if a hydrogen peroxide sensor is present, in which case the actual amount of hydrogen peroxide in gas phase in the chamber can be measured, and the time the first pump is active can be dynamically adjusted based on the measured value.

In particular, the first pump can be activated and remain activated until the measured value exceeds the target gas phase hydrogen peroxide concentration (e.g. 100 ppm). n) maintaining the hydrogen peroxide concentration in the chamber for a predetermined period of time (e.g., 60 min), and repeatedly updating the RFID tag(s) for the amount of hydrogen peroxide mixture in each of the reservoirs. This step n) corresponds to a second phase "phase 2" of the atomization process (see FIG. 14A to FIG. 14C).

* Maintenance of the hydrogen peroxide concentration can be carried out in open

loop, e.g. by repeatedly activating the first pump 405 with a certain duty cycle

(English: "duty-cycle"), e.g. every 5 minutes, turn the first pump ON for 1 minute, and turn OFF for 4 minutes, until the predetermined period (e.g. 60 min) has elapsed, (e.g. as shown in Fig. 15A); or e.g. every 5 minutes activate the first pump for a variable time (e.g.: "act1") to periodically add a certain amount of hydrogen peroxide mixture to the chamber (e.g. as shown in FIG. 15B);

* Servicing can also be performed in "closed loop" if a hydrogen peroxide sensor is present, in which case the first pump 405 can e.g.

can be switched off when the measured value of the H202 concentration in gas phase is lower than the predetermined value (e.g. 100 ppm), and can be switched OFF whenever the measured value exceeds a certain threshold value (e.g. 110 ppm or 120 ppm ), until the predetermined contact period (e.g., 60 min) is over.

o) actively lowering or passively decreasing the hydrogen peroxide concentration in the chamber to a predetermined value ("closed loop"), (e.g. less than 1.0 ppm), or for a predetermined time ("open loop") "); * If a scrubber or catalyst is present in the device (as e.g. with the "large fogger" of FIG. 3A and FIG. 4), then the second pump (in the scrubber 421) will be activated during the third stage, in order to allow an air stream to flow through the second fluid channel;

* If no scrubber or catalyst is present in the device (such as in the small fogger of FIG. 1A), nor externally connected to it, and if no hydrogen peroxide sensor is present, then this step includes "passively waiting for a certain period".

* If a hydrogen peroxide sensor is communicatively connected to the controller 415, it can be read repeatedly to determine when the gaseous hydrogen peroxide concentration in the chamber has dropped sufficiently before releasing the chamber.

If no hydrogen peroxide sensor is communicatively connected to the controller 415, then of course this is not possible, and then only a predetermined time can be passively waited.

* As an example, without a scrubber and without a catalyst, it can take eg 12 to 15 hours for the gaseous hydrogen peroxide concentration in the chamber to drop from 100 ppm to 1.0 ppm.

Thanks to the scrubber 412 with active carbon filter, this time can typically be halved.

* In a relatively simple embodiment of a nebulizer with an activated carbon scrubber, but without connection to an external hydrogen peroxide sensor, the duration of the third phase can be estimated using the following formula:

T3 (in seconds) = A3 + B3* Vchamber[3] where A3 is a predetermined time, e.g. 900 s, and where B3 is a value of 100 s/mp, and where Vchamber is the volume of the chamber (expressed in m3). But, of course, this is just an example, and the present invention is not limited thereto. * In a somewhat more complex embodiment, the time T3 depends not only on the volume of the chamber, but also on one or more of the following parameters: the hydrogen peroxide concentration in the hydrogen peroxide mixture used, the initial temperature in the chamber, the initial relative humidity in the room. This can be written mathematically as:

T3 = f4(H202 concentration in the hydrogen peroxide mixture, Tchamber, RVchamber, Vchamber),

This function can e.g. be established by performing tests under various conditions, and can e.g. be stored in tabular form in a non-volatile memory 216, 416 of the nebulizer.

FIG. 14A is an exemplary representation of an ideal course of the concentration of gaseous hydrogen peroxide in the chamber during a disinfection process. It should be noted that these graphs are not drawn to scale. The process consists of three phases: - in a first phase F1, hydrogen peroxide mixture is injected in atomized form into the chamber via the nozzle, or via two nozzles 3014, 301b in the example of

FIG. 3A. If the relative humidity of the air in the room is less than 100%, these droplets will evaporate, and the water (H20) of these droplets and the hydrogen peroxide (H202) of these droplets will be released in gaseous form. Tests have shown that the concentration of hydrogen peroxide in gaseous form in particular is decisive for the killing of micro-organisms. Tests have also surprisingly shown that the kill rate is many times greater when a silver stabilized hydrogen peroxide mixture is used (e.g. the product "Huwa-San TR-12.5", commercially available from Roam Technologies), compared to a hydrogen peroxide mixture without silver stabilization. For some micro-organisms the difference is even more than a factor of 10 or a factor of 100 times greater; - in a second phase F2, the hydrogen peroxide concentration in gaseous form in the chamber is kept substantially constant for a predetermined period of time (typically 60 minutes), also called "contact time"; or rather, it is ensured that the hydrogen peroxide concentration in gaseous form remains at least 100 ppm during this period. In practice, however, the hydrogen peroxide concentration will slowly decrease unless new droplets are injected into the chamber (see FIG. 14B and FIG. 14C). At the end of the second phase, the intended killing of the micro-organisms has been achieved. - in a third phase F3, the gaseous hydrogen peroxide concentration in the room must be reduced to a value of no more than 1.0 ppm before entering the room without a gas mask. As described above, a scrubber and/or a catalyst is preferably used during this third phase in order to accelerate the decrease of the hydrogen peroxide concentration in gaseous form.

Although not shown in FIG. 14A to FIG. 14C, a rinse with demineralized water can optionally be performed at the beginning of the third stage to clean the pipes and the nozzle, so that less corrosion occurs. This is not necessary for the atomization process or the killing process, but it will benefit the life of the device. To this end, the third reservoir 420 in the block diagram of FIG. 4, and the third valve V3. Typically there is a 1 minute "rinse", i.e. the first pump is activated, and air with water droplets is sprayed into the chamber, but the time to rinse can also be longer than 1 minute, or shorter than 1 minute.

The amount of hydrogen peroxide mixture required for the first and second phase together has already been described above. As a rule of thumb, it can be said that typically 40% to 60% of this is introduced into the chamber during the first phase, and the remaining amount in the second phase. The optimal ratio between the amount introduced into the first and second phase depends mainly on the volume of the chamber and the contact time, but also on the initial temperature and relative humidity of the chamber. This ratio can again be stored in tabular form in a non-volatile memory of the nebulizer.

FIG. 14A shows the ideal or theoretical course, but in practice the increase of the hydrogen peroxide concentration during the first phase is not linear, eg. not only because of the decreasing liquid flow rate (see FIG. 7), but also and above all because the evaporation of the droplets becomes more difficult as the process progresses, and more water vapor enters the chamber. In other words, during the first phase not only the gaseous hydrogen peroxide concentration increases, but also the relative humidity. When the relative humidity in the room has reached 100%, the air is saturated and the hydrogen peroxide concentration in the room cannot increase any further.

FIG. 14B shows an example of a sequence that could occur in practice when using open-loop control. Taking into account that the hydrogen peroxide concentration will decrease spontaneously during the second phase, it is preferable to blow slightly more liquid mixture into the chamber than in the ideal case, so that a point A' is reached which is slightly higher than the point A of FIG. 14A. During the second phase, the pump can be controlled intermittently, e.g. with a certain duty cycle, e.g. as shown in FIG. 15A or FIG. 15B, where the course of the hydrogen peroxide concentration (see FIG. 14B) is not perfectly flat in practice, but will show a kind of sawtooth. When the predetermined duration (e.g. 60 min) of the second phase has elapsed, optionally a short flush of the lines with demineralized water from the third reservoir 420 will take place, after which the hydrogen peroxide concentration in the chamber will decrease spontaneously or forced. Since FIG. 14B illustrates an "open loop" control, i.e. without effective measurement of the hydrogen peroxide concentration in gaseous form, it is not known exactly when the hydrogen peroxide concentration has fallen below 1.0 ppm. Therefore, in this case it is best to build in a safety margin before release the room.

FIG. 14C shows an example of a sequence that could occur in practice when using closed-loop control. In this case, the progression will also show a saw-tooth, but the first pump can be repeatedly selectively activated and deactivated based on the measured hydrogen peroxide concentration, in order to bring this value as close as possible to the target value (of e.g. 100 ppm), or to keep this value within a certain range (e.g. within the range of 100 ppm to 120 ppm). Thanks to the hydrogen peroxide sensor, it can also be determined exactly when the hydrogen peroxide concentration in the third stage F3 has dropped below 1.0 ppm, after which the chamber can be released.

FIG. 15A shows an example of a method of "intermittent fogging", which can be applied during the second stage phase2 of the atomization process in "open loop" control, performed by an atomization device that atomizes a liquid mixture, using the Venturi principle. In this example, a contact time T2 of 60 minutes is assumed, which is divided into 12 periods or intervals of 5 minutes each (N=1 to 12). Each interval includes an active portion during which the first pump is turned ON to nebulize, and a passive portion during which the first pump is turned OFF. In the example it is assumed that a remaining volume of "Vrest" of the mixture still has to be atomised.

Depending on the degree of filling at the beginning of the second phase, the nebulizer can calculate how long the first pump needs to be activated to atomize this amount.

Suppose that 500 ml is to be atomized in the second phase, and that the degree of filling is 100% (e.g. because the second reservoir is used). As shown in FIG. 8, the pump must be activated for 500 s to atomize this amount of mixture. In the example of FIG. 15A this time will be divided by 12, and the first pump will be turned ON every 5 minutes for 500/12 = approximately 41.7 seconds. By applying this time schedule (with fixed duty cycle), the same amount of mixture will not be blown into the chamber in each period, but only approximately, because the flow rate in the first period is approximately 62 |/min, and for the twelfth period about 55 ml/sec.

FIG. 15B shows a second example of an "intermittent fogging" method that can be applied during the second stage phase2 of the "open loop" fogging process. In this example, a contact time T2 of 60 minutes is again assumed, which is divided into 12 intervals of 5 minutes each (N=1 to 12), and it is assumed that another 500 ml needs to be nebulized, but in the scheme of FIG.15B (with variable duty cycle), the active time of each time slot is chosen such that the same amount of mixture is introduced into the chamber in each time slot, in the example 500 ml/12 = approximately 41.7 ml To achieve this effect, the first pump will have to be switched ON for a little less time in the first period, and should be switched ON a little longer in the twelfth period.

Of course these are just examples, and in practice other values can be used for e.g. the amount of mixture to be atomized (e.g.: 500 ml), the contact time (e.g.: 60 min), and the number of periods (e.g.: 12) .

However, the invention is not limited to an intermittent fixed period schedule as shown in FIG. 15A or FIG. 15B, (in the example: 60min / 12 = 5min), but it is also possible to choose the duration of the intervals differently, so that the first pump in each interval will run for the same amount of time {as in FIG. 15A), but that the "injections" are spread out in such a way that a more regular H 2 O 2 concentration profile is obtained. In such a time frame, the first interval will be somewhat longer than that of FIG. 15A, and the last interval somewhat shorter, inversely proportional to the amount of liquid that will be atomized in that interval, in other words, proportional to the liquid flow rate.

FINALLY,

Although the invention has mainly been described with some specific parameters, e.g. at least 100 ppm as the target hydrogen peroxide concentration in gas phase at the end of phase1 and during phase2; 1.0 ppm or less as the target gas phase hydrogen peroxide concentration at the end of stage 3; 60 minutes as the duration of the second phase; etc., but of course the present invention is not limited thereto, and other values are also possible.

Although the invention was primarily described for a silver stabilized hydrogen peroxide mixture, commercially available under the name "Huwa-San TR-12.5", consisting of a mixture of 12.1 to 12.5 wt% hydrogen peroxide, 0.0059 to 0.0079 wt% silver as a stabilizer, and demineralized water (for the rest wt%), the present invention is not limited thereto, and other silver stabilized hydrogen peroxide mixtures can also be used, such as, for example, but not limited to the product, commercially available under the name "Huwa-

San TR-7.9", consisting of 7.5 to 7.9 wt% hydrogen peroxide, and 0.0042 to 0.0053 wt% silver as stabilizer, and demineralized water (the remainder wt%); or the product, commercially available under the name "Huwa-San TR-11.9", consisting of 11.5 to 11.9 wt% hydrogen peroxide, and 0.0057 to 0.0074 wt% silver as a stabilizer, and demineralized water (otherwise wt%).

For the sake of completeness, it should be noted that external hydrogen peroxide sensors for measuring hydrogen peroxide in gaseous form are commercially available. For example, the following sensor can be used: “DrägerSensor® H202 LC - 6809705" in embodiments of the present invention. This sensor can accurately measure the hydrogen peroxide concentration in gas phase both during the first and second phase (where a value of e.g. 100 ppm is targeted), as well as during the third phase (where a value of e.g. 1.0 ppm is targeted).

While individual features have been illustrated in various drawings and in various embodiments of the present invention, it is contemplated that features of various embodiments may be combined, as would be obvious to those skilled in the art upon reading this document.

Claims (21)

CONCLUSIONS: An atomizing device (100; 200; 300; 400; 500) for atomizing a hydrogen peroxide mixture for disinfecting a room, the atomizing device comprising: - a first fluid circuit with a first pump (205; 405), and having a first inlet (IN1) for receiving a first gas stream from the chamber, and with means for adding droplets of a hydrogen peroxide mixture to this first gas stream, and with a first outlet (OUT1) for supplying this first gas stream with this droplets to the chamber; - a control unit (215; 415) for controlling the first pump (205; 405); - wherein the atomizing device has at least one connection for connecting at least one replaceable reservoir (202; 4024, 402b) containing a hydrogen peroxide mixture to the first circuit; - and wherein the at least one reservoir carries an RFID tag (203; 4034, 403b) that stores data comprising at least an amount of the hydrogen peroxide mixture; - and wherein the nebulizer device further comprises at least one RFID reader-writer (204; 4023, 404b) communicatively connected to the control unit (415), and arranged to read data from the RFID tag of the at least one container; - and wherein the control unit is further arranged to repeatedly write to the RFID tag to update the amount of hydrogen peroxide mixture on the RFID tag of the at least one container such that the data in the RFID tag, prior to a first update by the control unit, contain the initial amount of the hydrogen peroxide mixture in the reservoir, and such that the control unit repeatedly updates this amount stored in the data in the RFID tag to reflect the remaining amount of the hydrogen peroxide mixture in the reservoir, whereby the control unit ( 215; 415) is provided to update the amount of hydrogen peroxide mixture, taking into account a variable flow rate of the liquid mixture, the flow rate being dependent on the amount of hydrogen peroxide mixture still present in the at least one reservoir (202; 402a; 402b). An nebulization device (100; 200; 300; 400; 500) according to claim 1, wherein the control unit (215; 415) is further provided for: c) determining or receiving (1013) a volume of the chamber to be disinfected; d) determining (1014) the concentration of hydrogen peroxide in the hydrogen peroxide mixture in the at least one reservoir; e) estimating (1015) an amount of hydrogen peroxide mixture required to bring a predetermined gaseous hydrogen peroxide concentration into the chamber (stage 1), and maintain it for a predetermined contact time (stage 2); f) determining (1016) how much hydrogen peroxide blend is available in the at least one reservoir (102; 3024, 302b); g) giving an error message (1030) if the amount of hydrogen peroxide mixture present is less than the required amount of hydrogen peroxide mixture. A nebulizer device (100; 200; 300; 400; 500) according to claim 1 or 2, wherein the necessary amount of hydrogen peroxide mixture is determined using the following formula: NH=KV*A where NH is the necessary amount of hydrogen peroxide mixture (expressed in ml), and where KV is the volume of the chamber (expressed in cubic meters), and where A is a value (expressed in ml/m?) that depends on the hydrogen peroxide concentration in the hydrogen peroxide mixture. A nebulizer device (100; 200; 300; 400; 500) according to claim 1 or 2, wherein the necessary amount of hydrogen peroxide mixture is determined using the following formula: NH=KV*A where NH is the necessary amount of hydrogen peroxide mixture (expressed in ml), and where KV is the volume of the chamber (expressed in cubic metres), and where A is a value (expressed in ml/m?) calculated on the basis of the hydrogen peroxide concentration in the hydrogen peroxide mixture, and of one or several of the following parameters: Troom, RVroom, and Vroom, where Troom is the temperature of the room, RVroom is the relative humidity of the room, and Vroom is the volume of the room to be disinfected. An nebulizer device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the nebulizer device comprises at least one reservoir (102; 302a, 302b) containing a silver stabilized hydrogen peroxide mixture. A nebulizer device (100; 200; 300; 400; 500) according to claim 5, wherein the ratio of the weight percent hydrogen peroxide to the weight percent silver ions in the silver stabilized hydrogen peroxide mixture is a value in the range of 1500 to 2000. An aerosolization device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the data on the RFID tag (103; 3034, 303b) of the at least one reservoir (102; 3024, 302b) further comprises a value of a concentration of hydrogen peroxide in the hydrogen peroxide mixture; and wherein the control unit (215; 415) is further arranged to read this concentration value stored on the RFID tag. An aerosolization device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the data on the RFID tag (103; 303a; 303b) of the at least one reservoir (102; 3024, 302b) further comprises a contains an expiration date, and the nebuliser device is configured to determine the current date, compare the current date (1020) with the expiration date, and provide an error message (1030) if the expiration date has passed. An aerosolization device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the data on the RFID tag (103; 303a, 303b) of the at least one reservoir (102; 302a, 203b) further date of manufacture or an expiration date, and where the nebulizer is equipped to determine the current date, and is equipped to adjust the concentration of the hydrogen peroxide mixture read from the RFID tag in function of the date of manufacture or expiration on the one hand, and the current date on the other hand. An nebulization device (300; 400; 500) according to any one of the preceding claims, wherein the nebulization device further comprises a first valve (V1) for selectively connecting a first replaceable reservoir (402a) to the first fluid circuit, and further a second valve (V2) for selectively connecting a second replaceable reservoir (402b) containing a second hydrogen peroxide mixture to the first fluid circuit; and wherein the second reservoir (402b) has a second RFID tag (403b) that stores data including at least an amount of the second hydrogen peroxide mixture; and wherein the controller (415) is further configured to repeatedly update the RFID tag of the container from which hydrogen peroxide mixture is withdrawn. A nebulizer device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the nebulization device comprises a first RFID reader-writer (404a) arranged to communicate only with the RFID tag (403a) of the first reservoir (4023); and wherein the nebulization device comprises a second RFID reader-writer (404b) arranged to communicate only with the RFID tag (403b) of the second reservoir (402b). An nebulizer device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the RFID tag (203; 4034, 403b) is a passive RFID tag operating at a frequency of 13.56 MHz. A fogging device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the communication between the RFID tag and the RFID reader-writer is encrypted. An nebulizer device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the RFID tag (203; 403a, 403b) has a memory of at least 512 bytes, or at least 1024 bytes. A nebulizer device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the control unit (215; 415) is further provided to control the amount of hydrogen peroxide mixture of the RFID tag (203; 403a, 403b) of the update at least one reservoir (102; 4024, 402b) at least once per minute when fluid is drawn from that reservoir. An atomizing device (100; 200; 300; 400; 500) according to any of the preceding claims, wherein the first pump (205; 405) has a fixed speed, and wherein the control unit (215; 415) is arranged to control the first pump switch either ON or OFF; and wherein the first fluid circuit is arranged to add the droplets of hydrogen peroxide mixture to the first air stream based on the venturi principle. An atomizing device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the residual amount of hydrogen peroxide mixture in the at least one reservoir (202; 4024, 402b) is calculated in an iterative manner, taking into account the initial capacity and assuming that the instantaneous flow rate changes linearly as a function of the amount of hydrogen peroxide mixture in the at least one reservoir (202; 4024, 402b) between a first value associated with a substantially full reservoir and a second value associated with a substantially empty reservoir. An nebulization device (100; 200; 300; 400; 500) according to any one of the preceding claims, wherein the nebulization device has a second fluid circuit with a second pump (Pump2), and with a second inlet (IN2) for receiving a second gas stream from the chamber, and with means for removing hydrogen peroxide from the second gas stream, and with a second outlet (OUT2) for supplying this second gas stream with reduced hydrogen peroxide concentration to the chamber. An atomizing device (100; 200; 300; 400; 500) according to claim 18, wherein the means for removing hydrogen peroxide from the second gas stream comprises a catalyst. An atomizing device (100; 200; 300; 400; 500) according to claim 18, wherein the means for removing hydrogen peroxide from the second gas stream comprises a scrubber. An atomization system (590) comprising: an atomization device (100; 200; 300; 400; 500) according to any one of the preceding claims; and one or more external devices selected from: a hydrogen peroxide sensor (531), a temperature sensor (532), a relative humidity sensor (533), a remote control (540), a fan or fan (551), an air heater (552), a dehumidifier (553), an external scrubber (554), a laptop (541) or a tablet or a smartphone, the external device being communicatively connected to the control unit (215; 415) of the nebulizing device.