FI20215151A1 - Arrangement and method for controlling indoor conditions - Google Patents

Abstract

An arrangement (100) and method for controlling indoor conditions. The arrangement comprises - a programmable HV generator (G1) - at least two electrode elements (1, 2) - connected to the programmable HV generator (G1), - the programmable HV generator (G1) and the electrode elements (1, 2) arranged for creating an electric field between said electrode elements (1, 2), - a programmable control unit (3) for controlling the programmable HV generator (G1) such that - key properties of the electric field are arranged to be controlled in a programmable way, wherein - the key properties comprise at least one of the following: - polarity of the electric field, - arbitrary electric field generation, - a dynamic electrostatic field, - a steady state function, - the level of an electrostatic field generation.

Description

ARRANGEMENT AND METHOD FOR CONTROLLING INDOOR CONDITIONS

BACKGROUND The invention relates to an arrangement for controlling indoor conditions.

The invention further relates to a method for controlling indoor conditions.

Electrostatic fields may have a great influence on indoor conditions, and thus on likelihood of inflammatory ef- fects, infection, and contamination. However, current pre- cautions for controlling indoor conditions are incomplete and based mainly on the passive control and selections of materials.

BRIEF DESCRIPTION Viewed from a first aspect, there can be provided an ar- rangement for controlling indoor conditions, comprising - a programmable HV generator, at least two electrode ele- ments connected to the programmable HV generator, the pro- grammable HV generator and the electrode elements arranged for creating an electric field between said electrode ele- ments, a programmable control unit for controlling the = programmable HV generator such that key properties of the N 25 electric field are arranged to be controlled in a program- N mable way, wherein the key properties comprise at least 0 one of the following: polarity of the electric field, ar- r bitrary electric field generation, a dynamic electrostatic E field, a steady state function, and/or the level of an lo 30 electrostatic field generation.

O O An advantage is that an arrangement for controlling indoor conditions through controlling electric and electrostatic fields by active control measures and affecting contamina-

tion of airborne particles and/or for creating a desired electric field in a room may be achieved. Viewed from a further aspect, there can be provided a method for controlling indoor conditions, comprising - using a programmable HV generator and at least two elec- trode elements connected to the programmable HV generator, - creating an electric field between said electrode ele- ments by said programmable HV generator and said electrode elements, - controlling the programmable HV generator by a program- mable control unit such that - key properties of the electric field are controlled, wherein - the key properties comprise at least one of the follow- ing: - polarity of the electric field, - arbitrary electric field generation, - a dynamic electrostatic field, - a steady state function, - the level of an electrostatic field generation. An advantage is that a method for active controlling of indoor conditions through controlling electric and elec- trostatic fields and affecting contamination of airborne particles and/or for creating a desired electric field in S a room may be achieved. 5

LO — 30 The arrangement and the use are characterised by what is E stated in the independent claims. Some other embodiments — are characterised by what is stated in the other claims. = Inventive embodiments are also disclosed in the specifica- N tion and drawings of this patent application. The in- N 35 ventive content of the patent application may also be de- fined in other ways than defined in the following claims.

The inventive content may also be formed of several sepa- rate inventions, especially if the invention is examined in the light of expressed or implicit sub-tasks or in view of obtained benefits or benefit groups. Some of the defi- nitions contained in the following claims may then be un- necessary 1n view of the separate inventive ideas. Fea- tures of the different embodiments of the invention may, within the scope of the basic inventive idea, be applied to other embodiments.

In one embodiment, the electrode elements are arranged in a ceiling and in a floor of a room. An advantage is that a vertical indoor electrostatic field, such as a natural electrostatic field, can be cre- ated in the room. In one embodiment, at least some of the electrode elements are arranged in a wall(s) of the room.

An advantage is that at least partially horizontal indoor electrostatic field can be created in the room. In one embodiment, the electrode elements comprise a plate-type electrode element. N An advantage is that homogeneous or deflected electrostat- N ic field can be created for specific applications. oO 0 — 30 In one embodiment, the electrode elements comprise an ele- E ment comprising needle-type electrodes, preferably ar- — ranged in the ceiling, and that the programmable control = unit is arranged for creating an ionizing electric field N between the electrode elements, such that in the electric N 35 field:

- a voltage exceeding the level that forms ionization in the application, said voltage being in range of up to 100 kV/m, preferably 15 kV/m at most, more preferably 12 kV/m at most, even more preferably 6 kV/m at most, is created, and - a frequency range from a steady state Direct current (DC) to 1 kHz with a duty cycle (ratio of pulse width) from 0 to 100 %. An advantage is that airborne particles may be charged up to a desired polarity and then removed from the room by e.g. electrostatically charged surfaces. In one embodiment, the electrode elements are arranged in the ceiling and in the floor of the room, and the program- mable control unit is arranged for creating a natural ver- tical indoor electrostatic field. An advantage is that wellbeing of human beings in the room may be supported. In one embodiment, the arrangement comprises a RF (radio freguency) shielding structure arranged for creating a RF shielding room, and that the arrangement is arranged for cleaning air of said RF shielding room. N An advantage is that conditions that are very pleasant N even for individuals being sensitive to electromagnetic P fields can be created in the room. - 30 E In one embodiment, the programmable control unit is ar- — ranged for creating an artificial indoor electrostatic = field in the roon.

N N 35 An advantage is that the indoor environment can be adjust- ed to comply with case specific requirements of applica-

tions and people. Treatment of hypersensitive patients can also be adjusted to meet personal specific requirements. In one embodiment, the arrangement comprises a cleaning 5 element, such as an electrostatic attraction element or collecting surface, an electrostatic filter, a HEPA fil- ter, or a ventilation system, arranged for catching air- borne particles, and wherein the programmable control unit is arranged for creating an electric field between the cleaning element and one or more objects in the room. In one embodiment, the cleaning element is provided with electrodes for creating an electric field therein, and key properties of said electric field are arranged to be con- trolled by the programmable control unit in a programmable way, wherein the key properties comprise at least one of the following: the polarity of the electric field, an ar- bitrary electric field generation, a dynamic electrostatic field, a steady state function, and the level of an elec- trostatic field generation. An advantage is that cleaning effectiveness of the clean- ing element can be optimized and airborne particles can be removed from the room effectively.

In one embodiment, the arrangement comprises at least one N passive electrostatic discharge (ESD) control element ar- N ranged in at least one of the surfaces of the room and P furniture in the room. - 30 E An advantage is that electrostatic field between individu- = als may be reduced in the room. io N In one embodiment, the arrangement comprises at least one N 35 switch arranged for connecting and disconnecting the elec- trode(s) with the earth.

An advantage is that properties of the electrostatic field, such as polarity thereof, in the room may be changed quickly.

In one embodiment, the programmable HV generator, the at least two electrode elements and the programmable control unit are arranged into a portable equipment kit. An advantage is that the arrangement can be moved from one room to another room as needed. In one embodiment of the method, the electrode elements comprise an element comprising needle-type or thin wire electrodes, preferably arranged in the ceiling, and in the method - an ionizing electric field is formed by needle or thin wire type electrode, - a voltage exceeding the level that forms ionization in the application, said voltage being in range of up to 100 kV/m, preferably 15 kV/m at most, more preferably 12 kV/m at most, even more preferably 6 kV/m at most, is created, and - a freguency range from a steady state Direct current (DC) to 1 kHz with a duty cycle (ratio of pulse width) _ from 0 to 100 %.

S eu An advantage is that airborne particles in the room can be 7 charged and then removed based on their charge. Ek 30 BRIEF DESCRIPTION OF FIGURES = Some embodiments illustrating the present disclosure are 2 described in more detail in the attached drawings, in = which

N Figure 1 is a schematic view of an arrangement and method,

Figure 2 is another schematic view of an arrangement and method, and Figure 3 is a schematic illustration of detail of an ar- rangement.

DETAILED DESCRIPTION Figure 1 is a schematic view of an arrangement and method for controlling electric fields. The arrangement and meth- od are especially suitable for creating a desired electric field in a room. In an embodiment, the arrangement 100 may be arranged in at least one room H. The room H may be a room open for public, such as a lobby, a hall, a shop, a store, a shop- ping center, a theatre, a cinema theatre, an airport, for instance. The room H may also be a private room. The room H may be in a building built stationary in its site, or in a structure temporarily built, such as a tent or shelter.

In an embodiment, the room H is a room in healthcare or wellbeing activities, comprising medical locations, such as intensive care units, operating theatres, imaging rooms, inpatient wards, corridors, waiting rooms and con- sulting rooms.

N N In an embodiment, the room H is a room arranged for indus- S try applications, such as a clean room, an automated D eguipment hall, a workplace, a workstation, etc. = 30 = The room may also be in a means of transportation, such as D a car, a bus, a train, a tramway wagon, a ferry, a ship, = an aeroplane etc.

N In an embodiment, the arrangement and the method are used for cleaning air by removing small particles from said air. Electric field created by the arrangement urges elec- trically charged particles to move in a direction of field lines in homogeneous field. In an embodiment, the arrangement and the method are used for removing pathogen(s) in the room air. Said pathogen (s) may comprise e.g. virus(es) and/or bacteria. Said vi- rus (es) may comprise e.g. enveloped virus(es), such as co- rona virus (s).

According to an aspect, the arrangement and the method ac- cording to this disclosure makes it possible to clean in- door air without effective movement of air. It is to be noted that air cleaning without effective movement of air cannot be achieved with current air purifiers. In an embodiment, the arrangement and the method are used for creating an environment wherein an exposure to an electromagnetic fields (EMF) can be reduced and symptoms caused by an electromagnetic hypersensitivity (EHS) can be avoided or at least alleviated. In an embodiment, the arrangement and the method are used for reducing electrostatic attraction and contamination that may effectively reduce infections and improve immuni- _ ty in controlled areas.

S & In an embodiment, the arrangement 100 comprises a program- P mable high voltage (HV) generator G and at least two - 30 electrode elements 1, 2 connected to the programmable HV E generator Gi. In an embodiment, the high voltage (HV) — means voltage 100 V or more. In an embodiment, such as = shown in Figure 1, the arrangement 100 comprises one first N electrode element 1 and one second electrode element 2. N 35 However, it is to be noted that there may be more than one first electrode elements 1 and more than one second elec- trode elements 2 in the arrangement. The programmable HV generator G; and the electrode ele- ments 1, 2 create an electric field between the electrode elements. The programmable HV generator comprises a pro- grammable control unit 3 and a converter 11. The program- mable control unit 3 is configured to control the program- mable HV generator Gi by controlling the converter. In an embodiment, the converter 11 is a DC-HV converter. In an embodiment, the converter 11 is an DC-AC-HV converter. In an embodiment, the programmable HV generator G, comprises both the DC-HV converter and the DC-AC-HV connected paral- lel.

In an embodiment, the programmable control unit 3 is con- figured to control not only the HV Converter 11 but also the electrode elements 1, 2. In another embodiment, the programmable control unit 3 is configured to control just the programmable HV generator Gi. In an embodiment, such as shown in Figure 1, the program- mable control unit 3 is arranged in the programmable HV generator Gi, i.e. in the same cabinet or casing with the N converter 11. In another embodiment, the programmable con- N trol unit 3 is arranged outside of said cabinet or casing, <Q in another cabinet or casing. - 30 E In an embodiment, such as shown in Figure 1, the cabinet — or casing is provided with an interface 12 through which = the programmable HV generator can be controlled by a user. N In an embodiment, the interface 12 comprises physical con- N 35 trolling means, such as a keyboard, a keypad and/or a touchpad. In an embodiment, the interface 12 comprises an interface for connecting the programmable HV generator with a remotely arranged control unit (not shown) such as a personal computer, a laptop, a tablet computer or a smartphone. Such an interface may comprise a wifi inter- face or radio frequency antenna, a Bluetooth interface, an USB interface, a serial port, for instance. The remotely arranged control unit may be placed e.g. in the room H, a separate control room (not shown) or some other place out- side the room H.

The programmable control unit 3 may comprise a microcon- troller, or a programmable logic unit, for instance. The programmable control unit 3 may comprise a processor (CPU) with a memory configured to store program code and dynamic data. The programmable control unit 3 is configured to control key properties of the electric field created in the room. According to an aspect, the key properties of the electric field comprise at least one of the following: - the polarity of the electric field (this may comprise e.g. selectable unipolar or bipolar electric field genera- tion), - an arbitrary electric field generation (comprising un- N limited options of electric fields within certain limits), N - a dynamic electrostatic field (programmable frequency, <Q waveform and pulse width of electrostatic field), - 30 - a steady state function, and E - the level of an electrostatic field generation. = 5 In an embodiment, the arbitrary electric field generation N comprises making a program code for realizing the desired N 35 HV signal and electric field, and then running the program code in the programmable control unit 3. The programmable control unit 3 has unlimited options to create electric fields within the technical limits described in this dis- closure.

In an embodiment, the arbitrary electric field generation comprises allowing the programmable control unit 3 or the remotely arranged control unit to select randomly or inci- dentally the properties of the HV signal and the electric field.

In an embodiment, such as shown in Figure 1, the first electrode element 1 is arranged in a floor 5 and the sec- ond electrode element 2 in a ceiling 4 of the room H.

In an embodiment, the electrode elements 1, 2 arranged in the ceiling 4 and in the floor 5 are controlled by the programmable control unit 3 such that a natural vertical indoor electrostatic field is created in the room H. The “natural vertical electrostatic field” means an electro- static field that corresponds or is even equal with the natural electrostatic field prevailing outdoors.

In another embodiment, the electrode elements 1, 2 are ar- ranged in walls of the room H. In still another embodi- ment, there are electrode elements 1, 2 in the wall(s), in the ceiling and/or in the floor 5. There may be more than N one first electrode element and more than one second elec- N trode element in the room H.

I

LO A 30 In an embodiment, the electrode element 1, 2 is a plate- E type electrode element that can be made of conductive or = electrostatic dissipative materials.

io N In an embodiment, the arrangement 100 comprises at least N 35 one switch that is controlled by the programmable control unit 3 and arranged to connect and disconnect at least one of the electrodes 1, 2 with the earth. Thus, the key prop- erties of the electric field in the room H can be changed if needed during use of the arrangement and method.

In another embodiment, the position or state of the at least one switch is defined and locked at a start-up or boot of the programmable HV generator Gi. Thus, the key properties of the electric field in the room H are not to be changed by controlling the switch(es) during use of the arrangement and method.

In an embodiment, such as shown in Figure 1, the arrange- ment 100 comprises five switches S1 - S5. However, number of switches may vary. The switch fulfils high voltage switching requirements that depend on switching parame- ters.

In an embodiment, the arrangement 100 is devoid of the switches. In this embodiment, the key properties of the electric field are controlled by controlling just the con- verter 11.

The programmable control unit 3 may control the electro- static field so that a unipolar electrostatic field is created in the room H. The concept "unipolar electrostatic field” means that the potential gradient is completely on N the one side of the earth potential. The unipolar electro- N static field may be realized e.g. by closing a first ? switch S1 or a second switch S2 to the earth while remain- - 30 ing two switches are open, i.e. not connecting to the E earth.

= 5 In an embodiment, the natural positive vertical potential N gradient existing in the nature outdoors is simulated in N 35 indoor environment, i.e. in the room H.

The programmable control unit 3 may control the electro- static field so that a bipolar electrostatic field is cre- ated in the room H. The concept “bipolar electrostatic field” means that the potential gradient has both polari- ties.

Bipolar electrostatic field is realized by disconnecting S1 and S2 and by connecting S3 to the earth.

If it is needed a bipolar switching, i.e. chancing the po- tential gradient from one side to another side of the earth potential, it may be realized with changeover switching of S1 and S2 while S3 is open. Changeover switching of S4 and S5 can also be used.

It is to be noted that in the Figures V1 and V2 describe voltages at outputs of the programmable programmable HV generator, Cl and C2 are capacitances between the elec- trode 1 or 2 and earth, and R1 and R2 are safety resistors limiting current in case of accidental touching of high voltage.

In an embodiment, the arrangement 100 comprises a RF (ra- dio frequency) shielding structure 7 that establishes a RF shielding around the room H. The RF shielding structure 7 may reduce the coupling of radio waves, electromagnetic N fields, and electrostatic fields from outside the room in- N to the room, thus raising an electromagnetic hygiene of P the room H.

LO TT 30 E In an embodiment, The RF shielding structure 7 is a con- = ductive enclosure also known as a Faraday cage.

io N In an embodiment, the programmable control unit 3 is con- N 35 figured to create an artificial indoor electrostatic field. Depending on the placement of the electrode ele-

ments 1, 2, the electrostatic field may be a vertical field (such as shown on Figure 1), a horizontal field or a field having a vertical and a horizontal component.

In an embodiment, the arrangement 100 comprises a cleaning element 8 that is able to catch airborne particles. The programmable control unit 3 can be configured to create an electric field that promotes airborne particles to enter in the cleaning element 8. In an embodiment, the program- mable control unit 3 creates such an electric field be- tween the cleaning element 8 and one or more objects in the room H. The object may be e.g. a furniture, a picture, a curtain, a carpet, or a (cinema) screen. In an embodi- ment, the cleaning element 8 is arranged in the object.

In one embodiment, the cleaning element 8 is provided with electrodes for creating an internal electric field in said cleaning element. In one embodiment, the cleaning element 8 1s provided with electrodes for creating an ionizing electric field in said cleaning element. The key proper- ties of said electric field are arranged to be controlled by the programmable control unit in a programmable way, wherein the key properties comprise at least one of the following: the polarity of the electric field, an arbi- trary electric field generation, a dynamic electrostatic field, a steady state function, and the level of an elec- N trostatic field generation. This kind of cleaning element N 8 may receive air from the room H and return cleaned air <Q back in the room H, or it may receive air outside the room - 30 H and feed it in the room H.

i — In one embodiment, the arrangement comprises only the = cleaning element 8 provided with the electrodes, and the N room H is devoid of the electrodes 1, 2. In another embod- N 35 iment, the arrangement comprises the cleaning element 8 provided with the electrodes, and also the electrodes 1, 2 arranged in the room H.

The cleaning element 8 may comprise an electrostatic at- traction (ESA) element and/or collecting surface, an elec- trostatic filter, a High-efficiency particulate air (HEPA) filter, a room ventilation system, for instance.

In an embodiment, the arrangement 100 comprises a passive electrostatic discharge (ESD) control element 9 that re- duces indoor electrostatic fields e.g. between people in the room.

In an embodiment, the ESD element 9 is arranged to the floor 5. The ESD control element 9 is a passive el- ement that reduces or mitigates electrostatic fields due to its material selections.

The ESD conrol element 9 com- prises anti-static, conductive and/or dissipative material However, the ESD control element 9 may be arranged to any surfaces of the room.

The ESD control element 9 may also be arranged in the object(s) described above.

In an embodiment, the arrangement 100 comprises an adjust- able ventilation system that is able to maintain a suffi- cient air flow in the room.

A laminar airflow from the ceiling to the floor is preferred.

N Figure 2 is another schematic view of an arrangement and N method.

The arrangement and method are especially suitable P for removing particles in indoor air and for neutralizing - 30 static charges. i — In an embodiment, at least one of the electrode elements = 1, 2 comprise an element comprising needle-type or thin N wire type electrodes 6, preferably arranged in the ceiling N 35 4. The number of the needle-type electrodes 6 as well as their sizing and mutual positioning may vary.

In an embodiment, the programmable control unit 3 is con- trolling the needle-type or thin wire type electrodes 6 so that an ionizing electric field between the electrode ele- ments 1, 2 is created. In an embodiment, said ionizing electric field has a voltage in range of up to 100 kV/m, preferably 15 kV/m at most, more preferably 12 kV/m at most, even more preferably 6 kV/m at most, and a frequency range from a steady state Direct current (DC) to 1 kHz with a duty cycle (ratio of pulse width) from 0 to 100 %. Airborne particles and unearthed objects can be charged up to the desired polarity with the ionizing electric field. Charged particles may then be removed from the room H by e.g. cleaning elements 8, such as electrostatic attraction (ESA) elements or collecting surfaces.

It is to be noted, that the embodiments described in con- nection with Figure 1 may also be connected or combined with the embodiments described in connection with Figure

2.

In an embodiment, such as shown in Figures 1 and 2, the arrangement 100 has been built in the structure of the room H. In another embodiment, the arrangement is a mobile arrangement that can be mounted in one room, demounted from said room and again mounted in another room. In an embodiment, the programmable HV generator Gl, the at least N two electrode elements 1, 2 and the programmable control N unit 3 are arranged into a portable equipment kit. oO 0 — 30 Figure 3 is a schematic illustration of a programmable HV E generator Gi. = D In an embodiment, the programmable HV generator G, com- N prises a line power module 13, an interface 12 (as de- N 35 scribed in this description), a programmable control unit 3, an indicator module 15, and a converter (DC-DC HV con-

verter or DC-AC HV converter) 11. In an embodiment, such as shown in Figure 3, the programmable HV generator Gi further comprises a switching unit Si, - Ss and safety re- sistors Ri, Ro.

The invention is not limited solely to the embodiments de- scribed above, but instead many variations are possible within the scope of the inventive concept defined by the claims below. Within the scope of the inventive concept the attributes of different embodiments and applications can be used in conjunction with or replace the attributes of another embodiment or application. The description is only intended to illustrate the idea of the invention. The invention may vary in detail within the scope of the inventive idea defined in the following claims.

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REFERENCE SYMBOLS 1 first electrode element 2 second electrode element 3 programmable control unit 4 ceiling 5 floor 6 needle-type electrode 7 RF (radio frequency) shielding layer 8 cleaning element 9 ESD control element 10 wall 11 HV converter (DC-HV or DC-AC-HV) 12 interface 13 power supply 14 pre-amplifier 15 indication module 100 arrangement Ci, Co capacitance G1 programmable HV generator H room Ri, Ro Safety Resistor S1-S5 switch Vi, Vo Voltage nodes

N O N

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Claims (16)

1. An arrangement (100) for controlling indoor conditions, comprising - a programmable HV generator (Gi) - at least two electrode elements (1, 2) - connected to the programmable HV generator (Gi), - the programmable HV generator (Gi) and the electrode el- ements (1, 2) arranged for creating an electric field be- tween said electrode elements (1, 2), - a programmable control unit (3) for controlling the pro- grammable HV generator (Gi) such that - key properties of the electric field are arranged to be controlled in a programmable way, wherein - the key properties comprise at least one of the follow- ing: - polarity of the electric field, - arbitrary electric field generation, - a dynamic electrostatic field, - a steady state function, - the level of an electrostatic field generation.

2. The arrangement as claimed in claim 1, wherein - the electrode elements (1, 2) are arranged in a ceiling (4) and in a floor (5) of a room (FH). O

3. The arrangement as claimed in claim 1 or 2, wherein AN - at least some of the electrode elements (1, 2) are ar- 7 ranged in a wall(s) of the room (H). = 30 E

4. The arrangement as claimed in any of the preceding 5 claims, wherein [n - the electrode elements (1, 2) comprise a plate-type N electrode element. N 35

5. The arrangement as claimed in any of the preceding claims, wherein - the electrode elements (1,2) comprise an element com- prising needle-type electrodes (6), preferably arranged in the ceiling (4).

6. The arrangement as claimed in claim 5, wherein - the programmable control unit (3) is arranged for creat- ing - an ionizing electric field between the electrode elements (1, 2), such that in the electric field: - a voltage in range of up to 100 kV/m, preferably kV/m at most, more preferably 12 kV/m at most, even more preferably 6 kV/m at most, is created, 15 and a frequency range from a steady state Direct cur- rent (DC) to 1 kHz with a duty cycle (ratio of pulse width) from 0 to 100 % is produced.

7. The arrangement as claimed in any of the preceding claims, comprising - the electrode elements (1, 2) arranged in the ceiling (4) and in the floor (5), and - the programmable control unit (3) is arranged for creat- ing a natural vertical indoor electrostatic field. S

8. The arrangement as claimed in any of the preceding & claims, comprising <Q - RF (radio frequency) shielding structure (7) arranged - 30 for creating a RF shielding room, and that E the arrangement is arranged for cleaning air of said RF — shielding room.

O

O N

9. The arrangement as claimed in any of the preceding N 35 claims, wherein

- the programmable control unit (3) is arranged for creat- ing an artificial indoor electrostatic field in the room (H) .

10. The arrangement as claimed in any of the preceding claims, comprising - a cleaning element (8) arranged for catching airborne particles, and wherein - the programmable control unit (3) is arranged for creat- ing an electric field between the cleaning element (8) and one or more objects in the room (H).

11. The arrangement as claimed in claim 10, wherein - the cleaning element (8) is selected from: - electrostatic attraction (ESA) elements and col- lecting surfaces, - electrostatic filters, - HEPA filters, and - ventilation systems.

12. The arrangement as claimed in any of the preceding claims, comprising - a passive electrostatic discharge (ESD) element (9) ar- ranged in at least one of the surfaces of the room and furniture in the room. S 13. The arrangement as claimed in any of the preceding & claims, comprising ? - at least one switch (SI, S2, S3, S54, S5) arranged for - 30 connecting and disconnecting the electrode(s) (1, 2) with E the earth. = 5 14. The arrangement as claimed in any of the preceding N claims, wherein

N

- the programmable HV generator (G), the at least two electrode elements (1, 2) and the programmable control unit (3) are arranged into a portable equipment kit.

15. A method for controlling indoor conditions, comprising - using a programmable HV generator (G) and at least two electrode elements (1, 2) connected to the programmable HV generator (3), - creating an electric field between said electrode ele- ments (1, 2) by said programmable HV generator (Gi) and said electrode elements, - controlling the programmable HV generator (Gi) by a pro- grammable control unit (3) such that - key properties of the electric field are controlled, wherein - the key properties comprise at least one of the follow- ing: - polarity of the electric field, - arbitrary electric field generation, - a dynamic electrostatic field, - a steady state function, - the level of an electrostatic field generation.

16. The method as claimed in claim 15, wherein - the electrode elements (1, 2) comprise an element com- prising needle-type or thin wire type electrodes (6), N preferably arranged in the ceiling (4), and in the method N - an ionizing electric field between the electrode ele- ? ments (1, 2) is created, such that the electric field has - 30 - a voltage in range of up to 100 kV/m, preferably E 15 kV/m at most, more preferably 12 kV/m at most, — even more preferably 6 kV/m at most, and = - a freguency range from a steady state Direct N current (DC) to 1 kHz with a duty cycle from 0 to N 35 100 &%.