DE2007652A1 - Method and device for isolating a patient zone from the external environment - Google Patents

Description

PATENT ADVOCATE DR. HANS-GUNTHER EGGERT, DIPLOMA CHEMIST

5 KDLN-LINDENTHAL PETER-KINTGEN-STHASSE 2

Cologne, February 17th, 1970 Eg / Ax / I

Johnson & Johnson, 5 ° 1 George Street, New Brunswick, New Jersey (U.S.A.)

Method and device for isolating a patient area from the external environment

The invention relates to a performance and a method for controlling and regulating the environment in a localized area Zone, especially for the effective isolation of a patient from the external environment «,

Despite the introduction of numerous improved sterilization methods and antibiotic drugs in recent years are provoking infections to patients in the hospital, as before, the concern even of the flawless and very well run hospitals. These infections are particularly threatening for seriously injured or weakened patients and such Patients whose resistance is weakened by illness or exposure to immunosuppressive drugs is. Patients with extensive burns, premature births and patients with organs transplanted are examples of people who are seriously threatened by pathogenic microorganisms. To the same However, patients are admitted to the same hospitals for treatment of infections that are associated with are afflicted with the most dangerous pathogenic microorganisms.

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The need to prevent cross-contamination is evident and gave rise to the "familiar." Contraceptive methods such as antiseptic washes, sterilized facilities and clothing and embarrassing Cleanliness and tidiness. However, "there is still a way for the transmission of pathogenic microorganisms, namely the air currents in hospital rooms and corridors.

The risk of airborne contagion has been known for decades. Previous attempts to reduce the number of infections by cleaning the Reducing air in hospitals and / or directing airflow have shown promising results.

All known devices that serve to isolate a patient from the environment are from one or several of the following reasons and for other reasons objectionable: Adverse influence of the complete Conclusion on the mental state of the patient; high cost and complexity of renewing Setting up or changing an existing room construction; Inaccessibility of the patient to the nursing staff and the cost and difficulty of training personnel to operate the systems.

The invention has the object of eliminating all of the above-mentioned disadvantages and an extremely effective one and to provide simply constructed insulation units.

The invention relates to a mobile or portable device for protecting susceptible patients against Contagion from airborne bacteria by using a curtain at high speed flowing purified air that isolates the patient, but at the same time provides easy access for the nursing staff

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The device is preferred to be allowed to the patient designed to accommodate a standard hospital bed and to be lightweight Can be assembled and disassembled so that they can be anywhere in the hospital is needed, can be set up «The device not only protects the patient in the bed around which it is is built up, but also serves to reduce the contamination by bacteria in the immediate Environment by suction and filtration of the air in the room in which the device is in operation "

In contrast to previous developments in patient isolation, the device according to the invention does not physically enclose the patient in a relatively inaccessible enclosure. Instead, the device allows staff access to the bed as needed "takes you from the air-borne germs on imported, and filters and / or cleans the air before it is circulated _e has Apart from the benefit of the staff of protected Patient the psycho-

of logical advantage that he does not lock himself in and /

feels cut off from his surroundings. The patient can

Visitors see and höfeen without his g the air curtain

perceives "who" protected him and his visitors

The object set by the invention is achieved by a construction that covers the area of the patient with directed and regulated air currents isolated by the inductive effect of symmetrically arranged High speed air curtains can be created ". In a preferred embodiment, the Unit with two opposing load-bearing walls and two opposing openings between them Walls constructed, with a substantially rectangular zone in which the patient is housed, ge.

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forms · Sine perforated pressure chamber extends over the entire area of the patient, and an exhaust line is preferably under the floor near the floor placed on the patient's bed to evacuate the air moving up and down from the cabin.

The side edges of the pressure chamber along the open sides of the zone are provided with devices that curtains of high velocity air flowing over them direct the openings to protect them against contamination, contained in the air, to effectively close off and completely enclose the patient's area. Due to their symmetrical design, the air curtains not only close the area of the patient but regulate the flow patterns of the air the perforated pressure chamber so that the zone is kept with extremely low contamination at all times and within a short time after the introduction of bacteria into the area again on this minor contaminant degree of efficiency is brought.

The invention is described below in connection with the drawings which illustrate preferred embodiments.

Fig. 1 shows in perspective a designed according to the invention Isolation unit for patients.

Fig, 2 is a vertical section through the embodiment illustrated in Figure _# 1, air treatment device ·

Figure "3 is a vertical section through the controlled and controlled environment area of the set in Figure 1 · Darge apparatus and shows the Luftetrömungsbilder generated in this field"

Fig. 4- is a vertical section through another embodiment of the controlled and regulated exercise facility shown schematically and showing

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• the airflow patterns that occur within the area of the Patients are generated.

Pig · 5 is a graph showing the rapid Reinstatement of a low level of contamination in the patient's area illustrated after bacteria have been introduced into the field.

The insulating unit A for patients shown in Figure _e 1 comprises a controlled and regulated Umgebungsbereioh, which is shown at 10, and has a built-in air conditioning device. 11 The air treatment device 11 is the main load-bearing element of the entire unit and contains the air treatment equipment which will be described later. The subject of the invention is a device and a method for the effective isolation of a patient, who is tied to a bed 12, from the rest of the room provided with a second end wall 14, which can consist of Plexiglas or another suitable transparent material. The second end wall 14 provides a means for full Absehließung of lußteils of bed 12 and contributes ä simultaneously an end of the insulating unit · The walls 13 and 14 are both angled laterally outwardly from both sides of the insulating unit and impart to the unit in this way additional stability and limit the outer end of the air flow, which will be described below. The term "lengthways" used here means the direction from the head end to the foot end of the bed, while the "transverse direction" means the direction across the bed.

A pressure chamber 16 arranged at the top and an intake duct 17, in cooperation with one another, form the air distribution, which is necessary to the area 10 of the patient

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completely enclose and isolate the patient from the external environment. As shown in Pig. 1 and 3, the pressure chamber 16 consists of the top wall 18, two side walls 19 and 20 and two end walls 21 and 22. The end wall 22 is useful as part of the rear wall the air processing device 1.1 formed, such as shown in Pig. 3.

The internal construction of the pressure chamber is best illustrated in Pig · 3, which has a first perforated plate 24 between a top wall 18 and a second perfo- ■ A ured plate 25 is arranged. Two housings 26 and for fluorescent lamps are attached to the pressure chamber 16 and extend the full length of the area 10 of the patient around the interior of the isolation assembly to illuminate. Outside the housing 26 and 27 are two air guide slots 30 and 31 between the perforated Plates 24 and 25 and the side walls 19 and 20, respectively.

The air guide slot 30 (Pig.3) is elongated by two Plates 33 and 34 are formed which are pivotally attached to the underside of the pressure chamber 16. On two downwardly protruding fastening arms 35 and 36 ^ Adjusting screws 37 and 38 are attached, by rotating the pivoting distance of the plates 33 and 34 and the Distance between the plates can be adjusted. With this construction it is possible to control the air flow to flow out of the pressure chamber 18 within certain limits at any desired angle and the Adjust the width of the air flow emerging between the plates and the speed of the air curtain to regulate. The air guiding device 31 on the opposite side of the pressure chamber 16 is in the . the same way as the component 30 is formed, so dsJ . no description is required. Perforated panels 40 and 41 and above the air ducts

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and 31 arranged to provide an even flow of air the upper pressure chamber into the air guiding device guarantee"

The perforated flats 24 · »25, 40 and 41 have the Task, an even flow of air under static pressure from the upper pressure chamber into the area of the To ensure patient 10 while avoiding undesirable turbulence.

The suction channel 17 is generally rectangular with a closed top 43 and a closed front part 44 formed. Pages 45 and 46 of channel 17 | are arranged essentially vertically and perforated, so that the air can be sucked into the interior of the duct and fed to the air processing device 11

The air flow patterns formed in accordance with the invention and the advantages resulting therefrom are described below Described in more detail. First, however, the air treatment device 11 will be described for better understanding of the invention described in detail »The essential components of the air treatment device 11 are shown in FIG

the cross section with an inlet line §ο, / πι3-1; to the Suction channel 17 is in connection, and an outlet line 51 »which is connected to the pressure chamber 16 in connection I is shown.

The air treatment device 11 is comprised of a housing included that from the double-walled, with insulation filled panels 52 and 53, the front panel 54 (Fig.1) and the rear wall 55 and the top wall 56 and the lower wall 57 consists. A cooling device 58 is separate from the main device 11, preferably in a window or in another access to the outside, atmosphere arranged to avoid heating associated with their operation au. Units of this kind are well known. They preferably consist of

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a device in which the cooling liquid is in heat exchange relationship with an inert medium, e.g. Sole is within the unit for the transfer to the place to be cooled, in order to do this the possibility to avoid contamination if the coolant lines tear.

A vertical inner wall 59 and a perforated horizontal wall 60 are arranged in the housing delimited by the above-mentioned walls and plates and form an air cleaning chamber 61 therein.A horizontal wall 62 is arranged under the perforated wall 60 at a distance from this wall and forms with it an air pre-treatment chamber 63 · In the chamber 63, a heating coil 64 is arranged (not shown) to a suitable control 65 via a current source is connected. A temperature sensor 66 arranged in the chamber 61 is connected to the controller 65.

A transverse channel 67 'in connection with the horizontal Wall 62 is formed, connects the air chamber 63 with a return air inlet chamber 68. The chamber 68 is in turn connected to the intake channel 17 by the return line 50, which in the manner described by the Wall 52 of the device is performed. A fan 69 is arranged between the duct 67 and the return line 50, whereby the air is circulated in the manner indicated by the arrows in the figure.

A liquid container 70 is arranged below the channel 67 and stands with it through openings 71 and 72 in connection. A valve, which is shown as a movable flap valve 73, is in channel 67 between the Opening 71 and the opening 72 arranged what a Part of the air atroma passing through the channel from a Air treatment zone 74- diverted into the! Thanks 70 and can be returned directly to the chamber 63. This

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Valve provides an additional control for the device to create a regulated environment and is described in more detail below.

A heating coil 76 is arranged in the tank 70 and is connected to a suitable power source (not shown) is «A sensor, which can be a thermistor 80, is located in the tank 70 and is connected to the controller connected · The heating coil 76 and the sensor 80 are immersed in a liquid sump 82 in the tank 70.

A cooling coil 84 with flexible lines 86 with of the cooling device 58 is connected, also appears | in the sump 82 to the medium present therein Need to cool. The cooling device is also connected to the controller 78 so that by suitable Adjustment of this control is supplied to the sump 82 with heat through the heating coil 76 or through the cooling coil 84 can be removed therefrom in order to maintain a desired temperature therein

Devices with which such a control is possible are known. Since the device as such does not form part of the invention, it will not be described in further detail here. As mentioned above, the cooling device 58 belongs to the type in which the snake is cooled% 84 supplied cooling medium in heat exchange relationship with the refrigerant in the apparatus. In the device shown, this is achieved with the aid of a heat exchanger 88 in which the refrigerant, which is circulated through a refrigerant line 90, and brine, which is circulated through the coolant line 92 by a pump 94, are conducted in a heat exchange relationship with one another * An electrical pump 96 communicates with a number of spray nozzles 98 located in the air treatment zone 74 and with the liquid sump 62, whereby the liquid,

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which humidifies the air and adjusts the temperature, partly circulated continuously.

An important component of the air treatment device is the filter 100, which is designed in such a way that it fills the entire cross-sectional area of the cleaning chamber 61. The filter 100 is preferably a high efficiency particulate air (HEPA) filter that is capable of removing 99.97 to 99.9996 of all particles and bacteria 0.3 g and larger in diameter. Smaller particles become also by removing this type of filter, but the degree of removal has not yet been determined. The removal of smaller (particles is, however, insignificant, since bacteria are 0.3 to 30 a in size and are very rarely found in the air as dissolved individual cells, but usually cling to dust particles and flakes of skin that are much larger than the bacteria themselves · The mean diameter of particles carrying pathogenic bacteria in the air has been given to be about 12 µ over a range of 4 to 24 M. The microorganism which is mainly responsible for postoperative infections is the hemolytic Staphylococcus aureus, which has a diameter of about 0.5 M. The use of High performance air filters for removing tiny particles is well known * and the success of this filter has been proven beyond doubt.

Additional filters can be used in the air treatment device, e.g. pre-filters for removal large particles from the air before they get into the HEÜA filter, and activated carbon filters for removal of vapors and odors from the air. These pilter are not shown in the figures because they are known in air filtration technology.

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The PiItersystem makes an absolutely complete Purification of the air was achieved, however, it was found convenient to use a series of ultraviolet lamps 101 to be arranged in the air cleaning chamber 61. Ultraviolet radiation has been shown to cause deactivation of living microorganisms. It is used in this system as additional security. In Fig. 2 For example, the lamps 101 are shown at a location above the filter 100, but they can be anywhere in the air cleaning chamber 61 are arranged where appropriate.

The insulated walls described above contribute to the heat transfer between the chamber 61 and the ambient atmosphere to a minimum «This insulation can be made of any known material, z «B. Polyurethane foam, glass wool or the like «, or made of an evacuated space between the double walls. Any shapes of perforated walls are suitable for the chamber 61, however, is made of a hardboard with holes 6.4 mm in diameter and, for example, 12.7 mm Distance from center to center a perfect and even air flow through the chamber is achieved.

The heating coils 64 arranged in the chamber 63 are Conventional electrical coils that are connected to a suitable power source via a thermostat (not shown) are connected, through which the temperature of the coils is set and maintained in a suitable manner can be in order to finally bring the temperature and humidity of the gas stream to the desired value set immediately before its entry into the chamber 61. This final setting gives the opportunity to the properties of precisely regulating the gas flow.

When the device is in operation, the temperature control units 65 and 78 turned on, and the

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Pump 96 and fan 69 ″ cause the circulation of Gas through lines 50 and 51 and of liquid through gas treatment zone 74 · Diverted gas, the flows through the gas treatment zone 74 is saturated by the liquid atomized from the nozzle 98 and thereby moistened and at the same time on a temperature state brought, which is the temperature in the sump 82 approximated. The gas flow is then through the chamber 63 and passed through the heating coils 64, where the temperature and relative humidity of the gas flow are based the desired value in zone 10 can be finally set. By suitable regulation of the amount of gas, which is to flow through the zone 74 to be saturated at the predetermined temperature of the liquid in the sump 82 will be the relative humidity and the final temperature of the gas after passing through the Maintain heating coils 64 very precisely. The gas flow then passes through the perforated wall 60 and becomes by filtration in the filter 100 and exposure to ultraviolet radiation cleaned by lamps 101 »

The now completely conditioned and purified gas flows through the outlet line 51 into the upper one Part of the pressure chamber 16. The air then flows down through the perforated plates 24 and 25 into the zone of the patient, where it is evenly distributed at a relatively low speed. Simultaneously if air is expelled from the two air guide slots 30 and 31, as indicated by the arrows in Figure 3, thereby forming air curtains along the open sides of the area 10 of the patient. The air will then sucked through the perforated sides 45 and 46 of the channel 17 and into the inlet duct 50 of the air treatment svorri cht ung sucked in to be passed through the device and cleaned again.

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When radiation such as that emitted by the ultraviolet lamps 101 is brought into effect, a certain heating of the gas flow takes place during its circulation. However, by appropriately controlling the amount of heat transferred to the air through the heating coils 64 and by having a substantial volume of gas continuously flowing through the zone, very uniform temperature and humidity conditions can be maintained throughout the zone desired humidity and the desired temperature not exclusively through saturation and warming M

of the gas flow can be maintained, that can Valve 73 can be adjusted so that a predetermined proportion of the air flowing in the channel 67 through the Heating coils 64 is circulated «This branched off, not re-humidified air, which is mixed with that from the treatment zone 74 mixes exiting air flow, represents a further possibility of regulating the chimneys «

The foregoing description of the preferred embodiment of the invention shows that there is an improved apparatus to maintain a controlled and regulated Environment becomes available in a portable device. This preferred embodiment of the invention ^ has been described in connection with the use of air as a gas. However, it is obvious to that Expert that in the device described here with closed circuit an inert atmosphere, e.g. nitrogen, can be maintained in zone 10. It is also possible within the scope of the invention to use a gas mixture as the gas that is rich in oxygen, COp or CO can be »Furthermore, in addition to the Water injected into the gas stream to saturate it Other liquid treatment agents will be used to create a bactericidal or fungicidal atmosphere to be maintained in zone 10

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Special controls for regulating the temperature of the heating coils 64 or the temperature of the heating and Cooling coils 76 and 78 are not shown, but of course the most varied of commercially available ones can be used Apparatus including writers in the gas treatment device can be used according to the invention.

In Pig.4 is another embodiment of the invention shown. The same reference numbers are used here to denote the same parts that are also shown in FIG are to be designated. This embodiment is shown schematically as the only change in the device can be found in the construction of the suction line 17. Because the air curtains at high speed stream, they have a tendency to spread when they hit the floor. Hence the device modified by an additive that promotes the flow of air to duct 17. Adjustable Air baffles 105 and 106 are on the lower parts pages 45 and 46 attached. They catch the air curtain and direct it into the perforated sides of the Suction duct. As the air flow indicated by arrows shows, the luff is prevented from after the Reaching the zone of the suction channel spreads into the part of the environment outside the patient's area.

The above description is primarily concerned with the construction of the new insulation unit for Patient and the way this design works to the area of the patient at an extreme to keep the level of pollution at a low level and to prevent airborne microorganisms from entering the Prevent zone BU. However, the device has that as well important advantage that it has the ability to use the Sereioh the patient quickly returns to the low level of contamination to bring in working condition after

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Bacteria have entered the zone

In order to achieve an optimal speed of the return of the device to sterility, the direction and the speed of the air flow must be chosen carefully. In other words, the airflow patterns must be designed so that the area of the patient is quickly flushed free of bacteria, and this must be achieved with a minimum of air turbulence or turbulence _e

In the embodiment shown in Figure 3 found that to maintain the integrity of the air curtains 110 and 111 is the initial speed the one emerging from the loft braids 30 and 31 Air in the range of 51 to 915 m / minute, preferably He should be 520 m / down · This ensures that the main part of the air of the gate slope and substantially all of the indoor air is kept in the system and through the suction duct 17 out of the patient's zone is deducted. Experiments have shown that one normal volume of air delivered to the patient's zone, the initial velocity of the air curtains from 520 κ / hour at floor level to about 61 m / minute falls and at the entrance to the suction channel 17 rises again to 152 m / min.

The speed of air entering the area of the Patient entering through wall 25 is also important as it has a great impact on the flow conditions within the area and the velocity the renewed setting of the sterility in the device. As indicated by the arrows 112 in this zone indicated, the air is initially distributed vertically downwards into the zone, whereupon a clear division or Splitting the air along the approximate center line of the area of the head-end to the foot-end

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Patient takes place. This split is produced by the inductive effect of the air curtains flowing at higher speeds, and it is believed that this phenomenon is responsible for the very rapid return of the device to sterility. It has been experimentally found that the speed of the air 112 should be in the range of 1.5 m Ms 30 m / minute and that the preferred speed is 24 m / minute. This speed allows a portion of the air to descend in bed height, where it is caused to flow in the direction indicated by the arrows 113 in Figure 3 way "The entire LuftmasBe in the region of the patient is thus sweeps in constant motion and ^{n M} the contaminant-free zone without creating stagnant or turbulent areas that would prevent the system from returning to sterility.

The results of an important experiment are shown in 5 ¹ Ig.5. These results vividly illustrate the speed at which this device can purify itself of bacteria. The experiment was conducted as follows: while operating the device at the preferred air velocities noted above, three Reynier slit samplers were placed on the bed, sampler # 1 about two inches from the head of the bed at approx longitudinal center line of the patient area, sampler no.2 at a distance of about 56 cm from sampler no.1 to the foot end of the bed and sampler no.3 at a distance of about 56 cm from sampler no.2 to the foot end of the bed . A 4 ml aliquot of a suspension of Saroina lutea containing about 10 million viable bacteria per ml was placed in a # 40 Devilbiss nebulizer and air flow from a combined vacuum and pressure pump at a pressure of about

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1f4 kg / cm nebulized "The nebulizer was located in the patient zone about 30 cm from the head end of the bed and 30 cm below the pressure chamber" The nebulizer was allowed to generate a bacteria-laden mist for 2 minutes ". This time is shown on the graph in Fig _e 5 indicated as negative time The time zero on the graph indicates the time at which the nebuliser was switched off and the bacteria count started. Since the number of bacterial colonies picked up by sampler No. 1 during the first minute after nebulization was so extremely high and too large to be able to be determined, the curve representing this sampler is broken off above and ™ after Continued for about the first second, the second curve represents the number of bacterial colonies that appear in sampler # 2, and the bottom curve represents the bacteria picked up by sampler # 3.

Two very important conclusions can be drawn from the results of this experiment. Firstly, the patient zone of the isolation device, if this is operated under the preferred conditions, is absolutely completely freed of bacteria within 2 minutes after the intentional or unintentional introduction of bacteria into the patient zone λ. Second, regardless of the number of bacteria introduced into it and regardless of where the bacteria are introduced, the patient's area is cleared of bacteria within 2 minutes.

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Claims (21)

Pat entana-prohe )] Method for isolating a patient area from the external environment, characterized in that one a) the top, the bottom and the two opposite one another Encloses sides of this zone by a construction, b) cleaned, low-speed flowing Air evenly distributed from top to bottom into the zone through the closed top, c) closes the remaining opposite two sides W of the zone with curtains of air flowing at high speed; and d) sucks the air flowing at low and high speed from the bottom of the zone, 2) Method according to claim 1, characterized in that air curtains symmetrically on opposite sides of the zone and regulating the air flowing at low speed to awei Air flow patterns is formed, which are generated duroh the inductive effect of the air curtains. 3) Method according to claim 1 or 2, characterized in-P net that you clean the extracted air and the cleaned air through the closed top into the * Zone back. 4) Method according to claim 1 to 3, characterized in that the air is sucked off at tiner point, the is adjacent to the approximate longitudinal center line of the zone. 5) Method according to claim 1 to 4, characterized in that a bed is adjacent to the bottom of the zone is arranged » 009836/1493 6) Method according to claim 5 *, characterized in that the bed is set up so that its center line is in Longitudinal approximately with the center line of the zone in Longitudinal direction coincides. 7) Method according to claim 5 or 6, characterized in that that the head and foot sections of the bed are structurally enclosed are. 8) Method according to claim 5 to 7, characterized in that the air is sucked off from a point under the bed. 9) Method according to claim 1 to 8, characterized in that that the purified j | flowing at low speed Air an initial speed of 1.5 "to 51 m / minute and the curtains of air flowing at high speed are formed by air currents that form a Initial speed from 152 to 915 m / minute and one Have a top speed of 91 to 215 m / minute. 10) Method according to claim 1 to 9, characterized in that the initial speed of the low speed flow purified air about 24 m / minute, the initial speed of the air curtains about 520 m / minute and its top speed is 152 m / minute. 11) Device for isolating a patient zone from the external environment according to the method according to claims 1 to 10, characterized by a) Components (13, 14) to close off two opposite ones vertical sides of the zone (10), b) a pressure chamber (16) with at least one downwardly directed permeable wall (25, 26) over the Zone (10) is arranged, closes its upper part and flowing at low speed purified air vertically downwards evenly in 009836/1493 the zone (10) distributed, c) an air suction (17) and arranged at the bottom of the zone (10) d) at the edge of the pressure chamber (16) along the opposite one open sides of the zone (10) arranged components (50, 31), the curtains (110, 111) from with high Speed of air flowing between the edge of the pressure chamber (16) and the suction (17) downwards align and completely close off the zone (10). 12. The device according to claim 11, characterized in that the components arranged on the edge of the pressure chamber (16) (30, Jl) form the air curtains (110, 111) symmetrically on opposite sides of the zone (10), whereby the air distributed by the pressure chamber (16) along the approximate longitudinal direction of the zone (10) The center line is effectively divided into flow patterns by the inductive effect of the air curtains (111, 110) is transferred, which keep the zone (10) with an extremely low level of contamination and the zone (10) after Bring back the entry of bacteria back to this low level of contamination. 13. Apparatus according to claim 11 and 12, characterized by an air treatment unit (11) in connection with the suction (17) and the pressure chamber (16) for suction of air from the bottom of the zone (10) through the suction (17) * cleaning the air and supplying the cleaned Air to the pressure chamber (16) for distribution in the zone (10). 14. Apparatus according to claim 11 to 13, characterized in that that the components (30, 31) forming the air curtain (110, 111) consist of two spaced apart, elongated plates (33 * 3 * 0, which run along the The edge of the pressure chamber (16) are arranged and protrude from there downwards, so that a from the pressure chamber (16) 009836 / H93 incoming airflow one through the distance between the Plates (33, 34) certain desired thickness can be directed to the bottom of the zone (io). 15. The device according to claim 14, characterized by components (35, 36, 37, 38) for adjusting the distance * between the plates (33, 34) and the angular position of these plates to the pressure chamber (16). 16. The apparatus according to claim 11 to 15, characterized gekennzeinet that the suction means (I7) is generally rectangular and the air peppered by the vertical sides of the suction transit M is sucked. 17. The apparatus according to claim 11 to 16, characterized in that the suction (I7) along the approximate in The longitudinal center line of the zone (10) is arranged. 18. The device according to claim 11 to 17, characterized by baffles (I05, I06), which are at the lower part of the suction (17) are arranged and trap the air and guide it into the suction channel (17). 19. The device according to claim 11 to 18, characterized by a bed placed at the bottom of the zone (10). f 20. The device according to claim 19, characterized in that the bed is arranged so that its center line in the longitudinal direction on the approximate center line in the longitudinal direction of the zone (10) and components of the device complete the head and foot sections of the bed. 21. Apparatus according to claim 19 or 20, characterized in that the suction (I7) under the bed is arranged. 009-836 / 1493 Blank page