JP2012000124A - Infection prevention booth - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infection magnification preventing booth which can hold the relative humidity effective for the deactivation of an influenza virus, can hold the proper negative pressure, and can receive a patient comfortably.SOLUTION: The infection prevention booth includes: an enclosure for forming a clean booth indoors to cover a bed; a blower for purifying air in the booth and discharging it outside the booth; an auxiliary fan for forming an air circulation flow along the bed to cancel the nonuniformity of the air flow in the booth on the bed; a humidifier for adjusting the humidity in booth. A booth capacity formed by the enclosure is 6 m-15 m, an air inlet of about 100 cmis formed in the enclosure, the blower has a ventilation capacity of 0.1 m/minute-1.28 m/minute, a circulating air volume by the auxiliary fan is 1 m/minute-2.5 m/minute, a humidifying water quantity by the humidifier is at most 0.4 kg/hr, and the relative humidity in the booth is held at 45%RH-65%RH.

Description

  The present invention relates to an infection prevention booth, and more particularly, to an infection prevention booth suitable for accommodating or examining a patient infected with influenza.

  A positive pressure type simple booth is known as one of simple booths for accommodating patients (see, for example, Patent Document 1). This positive pressure simple booth can be used as a sterile room. In addition, there is a negative pressure type simple booth as another simple booth. As an example of this negative pressure type simple booth, a unit type negative pressure called “aero guardian” sold by Sanki Kogyo Co., Ltd. There is an isolation room. According to this isolation chamber, an opening is provided in the enclosure, and an FFU (fan filter unit) is provided on the opposite side of the enclosure from the opening. The FFU filters the air sucked through the opening through a HEPA filter and then discharges the air out of the isolation chamber, that is, the enclosure, thereby maintaining a negative pressure in the isolation chamber. Therefore, this isolation room can be used as an infection prevention booth for accommodating or examining a patient infected with influenza.

  By the way, the temperature range that people feel comfortable is a temperature range of 20 ° C. to 26 ° C., and based on the research results of the relative humidity range in which influenza is likely to be inactivated, it is 40 to 70% in the building environmental health management standards. RH is defined as the optimum relative humidity. Therefore, when the isolation room is used as an influenza infection prevention booth, it is desirable to maintain the isolation room at an appropriate relative humidity at which influenza is easily deactivated.

However, in the conventional isolation chamber, in consideration of the air flow rate sucked through the opening, in order to maintain an appropriate negative pressure in the isolation chamber, the FFU has a large flow rate exceeding 3.3 m ³ / min. Air volume is required. For this reason, in order to satisfy the condition of an appropriate relative humidity corresponding to this large air flow rate, an extremely large capacity humidifier is required. Application of such a large-capacity humidifier tends to cause uneven humidity in the isolation chamber. In addition, if the operating capacity of the FFU is increased in order to eliminate this humidity unevenness, noise problems and increased airflow will lead to a decrease in the patient's perceived temperature on the bed housed in the isolation room. May cause effects.

JP 2004-180724 A

  Therefore, an object of the present invention is to provide an infection spread prevention booth that can maintain a relative humidity effective for inactivation of influenza virus and can maintain an appropriate negative pressure, and can comfortably accommodate patients. It is in.

The infection spread prevention booth according to the present invention purifies the air in the clean booth for forming a clean booth covering the entire bed arranged in the room, and discharges the clean booth outside the clean booth. A blower, an auxiliary fan disposed in the clean booth for generating an air circulation flow, and a humidifier for adjusting the humidity in the clean booth. The clean booth capacity formed by the enclosure is not less than 6 m ^{3 and not} more than 15 m ³ , an air intake of substantially 100 cm ² is formed in the enclosure, and the blower is 0.1 m ³ / It is operated with a blowing capacity of at least 1 minute and not more than 1.28 m ³ / minute. The circulating air flow rate by the auxiliary fan is not less than 1 m ³ / min and not more than 2.5 m ³ / min, and the moisture content by the humidifier is not more than 0.4 kg / hr. The relative humidity in the booth is maintained at 45% RH or more and 65% RH or less.

In the infection prevention booth according to the present invention, as described above, the clean booth capacity is 6 m ³ or more and 15 m ³ or less, and an air intake of substantially 100 cm ² is formed in the enclosure. By operating the blower with a blower capacity of 0.1 m ³ / min to 1.28 m ³ / min, the inside of the clean booth can be sensed without causing the patient on the bed to feel noise or a decrease in temperature. Appropriate negative pressure can be maintained. In addition, by setting the circulating air flow rate by the auxiliary fan to 1 m ³ / min to 2.5 m ³ / min and the humidifying water amount by the humidifier to 0.4 kg / hr or less, The relative humidity in the clean booth can be maintained at 45% RH or more and 65% RH or less by the humidifier without causing uneven air flow or uneven humidity.

  The circulating air flow by the auxiliary fan eliminates uneven humidity in the clean booth. This makes it possible to achieve an optimum relative humidity with a smaller amount of humidified water from the humidifier.

  By using a steam-type humidifier as the humidifier, various bacteria contained in the water that is the source of steam generation can be sterilized and disinfected, so that the release of these bacteria can be prevented.

  The enclosure has a rectangular top portion that covers the top of the bed and a peripheral wall portion that hangs down from the top portion of the top portion to the floor of the room, and the air is formed by a gap between the lower edge of the peripheral wall portion and the floor. An intake can be formed. Instead, the space between the lower edge of the peripheral wall portion and the floor can be a sealed structure, and the air intake can be formed in a part of the peripheral wall.

  A quasi-HEPA or HEPA filter can be attached as a filter attached to the blower.

  According to the present invention, as described above, an appropriate negative pressure can be maintained in the clean booth without causing the patient on the bed to feel noise and a decrease in the temperature of the body, and the influenza virus can be deactivated. Therefore, an infection spread prevention booth that can comfortably accommodate patients and can effectively prevent the spread of influenza infection is provided.

1 is a perspective view schematically showing an infection spread prevention booth according to the present invention. It is a graph which shows the leakage characteristic of the floating fine particle of the infection spread prevention booth which concerns on this invention based on an experimental result. It is a graph which shows the relationship between the infection titer of airborne influenza virus and relative humidity based on an experimental result. It is Table 1 which shows the relationship between the circulating air flow based on a measured value, and relative humidity. It is Table 2 which shows the relationship between the circulating air flow based on a measured value, and relative humidity. It is Table 3 which shows the relationship between the circulating air flow based on a measured value, and relative humidity. It is Table 4 which shows the relationship between the circulating air flow based on a measured value, and relative humidity. It is Table 5 which shows the relationship between the circulating air flow based on a measured value, and the wind speed measured value near a patient's face. It is Table 6 which shows the measurement result which investigated the relationship between the amount of circulating ventilation, and a patient's draft feeling. It is a perspective view which shows the other example of the infection expansion prevention booth which concerns on this invention. It is a cross-sectional view which fractures | ruptures and shows a part of booth shown in FIG. It is a front view which shows the further another example of the infection expansion prevention booth which concerns on this invention, (a) shows the closed state of an entrance, and (b) shows the open state of an entrance.

  As shown in FIG. 1, the infection spread prevention booth 10 according to the present invention forms a rectangular frame 14 and a space 16 for accommodating the bed 12 in order to partition the outside of the bed 12. For this purpose, it is a blower comprising an enclosure 18 made of a soft synthetic resin such as transparent vinyl disposed over the frame body 14 and an FFU (fan filter unit) containing a filter 20a, for example. 16 includes a blower 20 for applying negative pressure to 16, a humidifier 22 for humidifying the space 16, and an auxiliary fan 26 for forming a circulating air flow 24 in the space.

  The bed 12 has a size of, for example, length (L1) × width (W1) × height (H1) of 1940 mm × 845 mm × 310 mm, and is installed on the floor of a hospital room, for example, although not shown. The frame 14 is installed on the floor, and the length (L2) × width (W2) × height (H2) along the height, width, and height is 2700 mm ×, for example, so as to cover the outside of the bed 12. Each frame has a size of 2300 mm × 2000 mm.

  The enclosure 18 has a rectangular shape corresponding to the ceiling frame portion of the frame body 14, and a rectangular top portion 18 a disposed on the ceiling frame portion, and a pair that hangs down continuously on the floor from a pair of long sides of the top portion. Side wall portions 18b and a pair of end wall portions 18c that continuously hang down on the floor from a pair of short sides of the top portion 18a. Fasteners 18d for releasably connecting the two adjacent vertical edges are provided at the adjacent vertical edges of the side wall portions 18b and the end wall portions 18c. A continuous annular peripheral wall portion (18b, 18c) is formed by 18b and the pair of end wall portions 18c.

The enclosure 18 forms a space 16 for accommodating the bed 12 by the coupling of the fasteners 18d. In the example shown in FIG. 1, a space 16 having a volume of 12.4 m ³ is formed. In addition, at least one fastener 18d allows the patient 28 or the doctor to enter and leave the space 16 by releasing the connection between the adjacent vertical edges 18b and 18c. In the example shown in FIG. 1, the lower edge of the continuous peripheral wall portion (18b, 18c) of the enclosure 18 is bent to the outside of the space 16 on the floor by a length of about 5 cm. A gap is substantially formed between the portion 18e and the floor.

As the enclosure 18 of the minimum size that can be accommodated without giving a feeling of occlusion to the patient 28 on the bed 12, the longitudinal (L2) × lateral (W2) × height (H2) of the enclosure is, for example, 2000 mm × 1500 mm × By using the enclosure 18 having each frame size of 2000 mm and the frame 14 suitable for the enclosure 18, a space 16 having a minimum volume of 6 m ³ can be formed.

In order to install medical devices in the space 16 as necessary, the length (L2) × width (W2) × height (H2) of the infection spread prevention booth 10 is set to, for example, 3000 mm × 2000 mm × 2500 mm. Can do. In this case, the space 16 has a maximum volume of 15 m ³ . Between the maximum volume and the minimum volume, the space 16 can be set to a desired volume and a desired dimension of length (L2) × width (W2) × height (H2).

  In the example shown in FIG. 1, the blower 20 made of FFU is installed on one end wall portion 18 c located on the foot side of the patient 28. The filter 20a provided in the blower 20 is a HEPA filter in which the collection rate of particles having a particle size of 0.3 μm in a rated flow is 99.97% or more.

  The size of a single influenza virus is 0.1 μm, but when released from the mouth or nose of the patient 28, the virus scatters and floats in a state of being wrapped in a protein derived from body fluid. Therefore, since the size of the virus is substantially floating as submicron particles several times larger than that of a single substance, even if a HEPA filter or a quasi-HEPA filter with a lower accuracy than this is used as the filter 20a, these particles are removed. be able to. Of course, a UPLA filter with higher accuracy than the HEPA filter can be used. However, in terms of durability, it is desirable to employ a quasi-HEPA filter or a HEPA filter.

The blower 20 operates to suck air in the space 16 and capture particles such as influenza virus with the filter 20a, and then discharge the purified air out of the enclosure 18. At this time, as described above, the bent lower edge portion 18e of the enclosure 18 is bent on the floor over a region having a length of about 5 cm. Therefore, a part of the bent lower edge portion 18e is in close contact with the floor, but the remaining portion is not in close contact with the floor, and a gap is partially retained, and this gap has a total opening area of about 100 cm ^2. Acts as a substantial suction opening. Even if it is assumed that the lower edge of the peripheral wall portion (18b, 18c) of the enclosure 18 has a uniform spacing of 1 mm between the gap and the floor, the total opening area is 100 cm ² . Not too much. Therefore, when the bent lower edge portion 18e is provided, it is considered that a small total opening area of about 100 cm ² is held substantially.

The blower 20 sucks air into the enclosure 18 through such a suction opening. In addition, thermal convection and natural convection of 10 to 15 cm / second, whose direction is not determined, occur in a large room where the infection prevention booth 10 is normally installed. It is necessary to maintain a negative pressure in the space 16 regardless of the direction of the air flow whose direction is not determined. Therefore, in order to generate a negative pressure with respect to the maximum air volume of 15 cm / second × 100 cm ² blown out backward from the suction opening, the air blower 20 needs an air volume exceeding this value. The value of this product becomes a 0.090m ³ / min, the peripheral wall portion (18b, 18c) in consideration of the flow rate of the air sucked from the fastener 18d etc., blowing the blower 20 of 0.1 m ³ / min or more By operating with capacity, the space 16 can be reliably held at a negative pressure.

  This negative pressure can prevent the influenza virus released from the patient 28 from leaking out of the enclosure 18, so that the space 16 can function reliably as a clean booth space.

Each bent lower edge portion 18e of the peripheral wall portions (18b, 18c) reliably prevents the lower edge portions of the side wall portions 18b and the end wall portions 18c from being lifted from the floor. ^It acts to reliably prevent exceeding ² . Therefore, the length of the bent lower edge portion 18e can be set to 5 cm or more as necessary. Further, as shown in the drawing, the bent lower edge portion 18 e can be formed in the space 16 instead of being formed in the space 16.

The graph shown in FIG. 2 is a graph showing the leakage characteristics of the suspended fine particles in the infection spread prevention booth 10. An infection spread prevention booth 10 having a volume of 6.3 m ³ was used as the infection spread prevention booth 10, and a total opening area of 100 cm ² acting as a suction opening similar to that described above was set in the booth. Further, an outer chamber for accommodating the infection spread prevention booth 10 was formed by an experimental cover covering the infection spread prevention booth 10. A HEPA filter was employed as the filter 20a.

  After spraying virus particles simulating the cough of the patient 28 using a nebulizer for 1 second in the infection spread prevention booth 10, laser particle counters in the infection spread prevention booth 10 and outside the booth, that is, in the outside chamber, respectively. Was used to measure the number concentration of suspended particles having a particle diameter of 0.3 μm or less.

  The horizontal axis of the graph shown in FIG. 2 shows the elapsed time (minutes) after the spraying of the virus particles, and the vertical axis shows the concentration of the number of captured particles (count number / 1 liter air). The operating flow rate of the blower 20 provided in the infection spread prevention booth 10 was adopted as a parameter. Characteristic lines 30 (30a, 30b), 32 (32a, 32b) and 34 (34a, 34b) are the measurement results when the operating flow rate of the blower 20 is 0 liter / minute, 97 liter / minute, and 191 liter / minute. Each characteristic line 30a, 32a, 34a and 30b, 32b, 34b is a measured value inside and outside the infection spread prevention booth 10 respectively.

  That is, the characteristic lines 30a and 30b show the change in the particle number concentration inside and outside the infection spread prevention booth 10 when the blower 20 is stopped. Immediately after the spraying of the particles, the concentration of the number of particles in the booth 10 increases rapidly and then maintains a substantially constant value. On the other hand, outside the booth 10, the particle number concentration approaches that in the booth 10 as time passes so that the characteristic line 30b approaches the characteristic line 30a. This indicates that the leakage of the particles occurs in the infection spread prevention booth 10.

  On the other hand, characteristic lines 32a and 32b indicate changes in the particle number concentration inside and outside the booth 10 when the operating flow rate of the blower 20 is set to 97 liters / minute. In this operating situation, the particle number concentration outside the booth 10 is kept below 10 count / liter air regardless of the passage of time. This means that there is no substantial leak in the booth 10 with respect to the particles. The characteristic lines 34a and 34b when the operation flow rate of the blower 20 is set to 191 liters / minute also show the same tendency as the characteristic lines 32a and 32b.

Therefore, also from the graph of FIG. 2, as described above, by operating the blower 20 with a blowing capacity of 0.1 m ³ / min or more, the space 16 can be reliably held at a negative pressure. , Leakage of particles of 0.3 μm or less to the outside of the infection spread prevention booth 10 is reliably prevented. As a result, the space 16 functions as a clean booth space that prevents the influenza virus released from the patient 28 from being discharged out of the enclosure 18.

  The humidifier 22 adjusts the relative humidity of the space by releasing water vapor into the space 16. Regarding this relative humidity, for example, in the “Law for Ensuring Hygienic Environment in Buildings” (commonly called Building Sanitation Management Act), relative humidity is 40 to 70% in a temperature range of 20 to 26 ° C. where people feel comfortable. RH is stipulated. In addition, regarding the relationship between relative humidity and influenza virus inactivation, Schaffer et al. (FLSchaffer, ME Soergel, and DCStraube, Survival of Airborne Influenza Virus: Effects of Propagating Host, Relative Humidity, and Comparison of Spray Fluids, Archives of Virology 51, 263-273 (1976) by Springer-Verlag 1976) reports that the inactivation of airborne viruses is particularly significant at 50% -55% RH.

In order to further clarify the relationship between relative humidity and influenza virus inactivation, the nebulizer was used in the 6.3 m ³ infection spread prevention booth 10 (temperature is 25 ° C.) similar to the graph shown in FIG. The virus particles were sprayed for 1 second using a, and after a lapse of a predetermined time, the floating influenza virus in the infection spread prevention booth 10 was captured using a gelatin filter as a sampling device, and the infectivity titer was determined. The experimental results are shown in FIG. By using a gelatin filter as a filter, it is possible to reliably collect suspended particles with a size of 1 μm or less, and capture 98% or more of any size particles with a size of 1 μm or less, including nanometer-sized suspended particles. I was able to gather.

  In the graph of FIG. 3, the elapsed time in an atmosphere of 25 ° C. is used as a parameter, the horizontal axis indicates relative humidity (% RH), and the vertical axis indicates infectivity titer (PFU / 40 liter air). The characteristic line 36a indicates that the elapsed time is zero, that is, the initial infection value. Characteristic lines 36b to 36e indicate the infectivity values after the lapse of 2, 10, 20 and 30 minutes after spraying, respectively. If there is a decrease in the infectious titer of 2 digits or more compared to the initial value, it can be determined that the state is substantially inactivated. Therefore, as apparent from the characteristic line 36d after 20 minutes, the influenza virus can be inactivated by maintaining the relative humidity at 45% RH to 65% RH after 20 minutes. it is conceivable that.

  The temperature in the infection spread prevention booth 10 was changed to 20, 22 and 26 ° C., and the relationship between the infection value and the relative humidity was determined. In both cases, the same results as those in the graph of FIG. 3 were obtained.

  Therefore, from the viewpoint of comfort, it is desirable to maintain the temperature in the space 16 at 20 to 26 ° C. At this time, in order to inactivate the influenza virus and promote early healing of the patient 28, the humidifier 22 The relative humidity in the space 16 is maintained at 45% RH to 65% RH based on the detected humidity from the humidity sensor incorporated in the.

  Further, the humidifier 22 for maintaining the relative humidity at 45% RH to 65% RH is placed on the inner side of the peripheral wall portion 18c on the head side of the patient 28, and the blast volume of the auxiliary fan 26 and the blower 20 is set. Therefore, in order to eliminate the humidity unevenness in the space 16, it is operated at a humidified water amount of 0.4 kg / hour or less.

  The basis of the humidified water content by the humidifier 22 and the value of 0.4 kg / hour will be described with reference to Table 4 shown in FIG. 4 and Table 4 shown in FIG. As shown in FIG. 1, the auxiliary fan 26 is diagonally related to the humidifier 22 on the foot side of the patient 28 like the blower 20 so that a circulating air flow 24 in the longitudinal direction of the bed 12 is generated. And suspended from the top 18a on the inner side of the peripheral wall 18c. The atmosphere outside the infection spread prevention booth 10 is 22 ° C. and 30% RH, and the control set value of the humidifier 22 is 55% RH.

Table 1-4, the circulating air volume of the auxiliary fan 26 ^{(m 3} / min) up to 0~2.5m ³ / min for each when changing every 0.5 m ³ / min, the floor at one point The measured values are shown at height positions from 60 cm, 120 cm and 180 cm, respectively.

Table 1 shows the result of the measured value when the humidification amount of the humidifier 22 is set to 0.2 kg / hour. Tables 2 to 5 show the results of measurement values when the humidification amount of the humidifier 22 is set to 0.3 kg / hour, 0.4 kg / hour, and 0.5 kg / hour, respectively. Considering the height of the bed 12, if the relative humidity is not uneven at the 120 cm and 180 cm height positions, it is considered that the unevenness has been eliminated, and the relative humidity required for the inactivation of influenza virus is 45%. RH to 65% RH indicates the amount of humidification of the humidifier 22 as shown in Table 1 shown in FIG. 4, Table 2 shown in FIG. 5, and Table 3 shown in FIG. When each table is set to 0.2 kg / hour, 0.3 kg / hour, and 0.4 kg / hour, and the air flow rate of the auxiliary fan 26 is set to 1 to 2.5 m ³ / minute, it is substantially relative. It is thought that the uneven humidity has been eliminated.

Therefore, in order to eliminate unevenness in relative humidity, it is necessary to set the air flow rate of the auxiliary fan 26 to 1 to 2.5 m ³ / min. Further, when the temperature outside the infection spread prevention booth 10 is 22 ° C., the temperature is a comfortable range of 23 to 26 ° C. at any point in the space unless a medical device as a heat source is brought into the space 16. It was in.

Tables 1 to 4 show examples in which the humidification amount of the humidifier 22 is changed between 0.2 kg / hour and 0.5 kg / hour as described above, but there is a relative humidity. In order to maintain the value, there is a proportional relationship between the amount of air blown by the blower 20 and the amount of humidified moisture of the humidifier 22. That is, it is necessary to prevent the relative humidity from being increased by increasing the air flow rate as the humidified moisture amount is increased, and to prevent the relative humidity from being insufficient by decreasing the air flow rate as the humidified water amount is decreased. In the case where Tables 1 to 4 are obtained, when the humidifier 22 has a moisture amount of 0.2 kg / hour, the blower 20 needs an air flow rate of 0.64 m ³ / min. Similarly, the humidifier 22 is 0.3 kg / time, when a water content of 0.4 kg / time and 0.6 kg / time, the blower 20 0.96 m ³ / min, 1.28 m ³ / min and An air flow rate of 1.6 m ³ / min is required.

Therefore, the humidified water amount of the humidifier 22 being 0.4 kg / hour means that the blower 20 has a blown amount of 1.28 m ³ / min. As shown in Table 4, when the humidified water content is 0.5 kg / hour, the air flow rate of the blower 20 is 1.6 m ³ / min, and the desired relative humidity is 45% RH to 65% RH. Since unevenness cannot be eliminated, it is necessary to set the air flow rate of the blower 20 to 1.28 m ³ / min or less in order to eliminate unevenness in relative humidity.

As a result, the air flow rate of the blower 20 is a lower limit air flow rate of 0.1 m ³ / min for maintaining the negative pressure necessary in the space 16 and an upper limit value that can eliminate the relative humidity unevenness in the space 16. It is necessary to set between 1.28 m ³ / min.

Furthermore, the relationship between the circulation air volume of the auxiliary fan 26 and the decrease in the sensible temperature felt by the patient 28 on the bed 12 in the infection spread prevention booth 10 was examined. At this time, the air flow rate of the blower 20 was set to 1.28 m ³ / min, which is the upper limit value, and the humidified water amount by the humidifier 22 was set to 0.4 kg / hour.

  Further, the height of the bed 12 is set to 50 cm, and the circulating air flow 24 is formed in the space 16 by the auxiliary fan 26 which is directed obliquely upward by 30 degrees from the foot side of the subject (28) lying on the bed 12 did. Furthermore, the direction of the auxiliary fan 26 was set so that the extension of the central axis of the auxiliary fan 26 deviated from the body of the subject (28) so that the straight airflow would not reach the body of the subject (28) directly.

  There were five subjects (28) who judged whether or not the temperature of the body was lowered, that is, whether or not there was a draft sensation. Was used. Table 5 shows the measurement results.

Table 6 shows the result of the presence / absence determination of the subject's draft feeling. As is clear from the correspondence in Tables 5 and 6, when the maximum wind speed near the face exceeded 15 cm / second, the subject (28) felt an uncomfortable draft feeling. In order to prevent the maximum wind speed near the face from exceeding 15 cm / second, the circulating air flow 24 generated in the space 16 under the operation of the auxiliary fan 26 has a circulating air volume of 2.5 m ³ / min or less. There was a need to keep. Further, similar results were obtained in the case where the auxiliary fan 26 was installed 30 degrees downward from the foot side, 30 degrees upward from the head side, and 30 degrees downward from the head side.

As is clear from the above,
1. The clean booth capacity, that is, the capacity of the space 16 is not less than 6 m ^{3 and not} more than 15 m ^3, and an air intake of substantially 100 cm ² is formed in the enclosure 18,
2. The blower 20 is operated with a blowing capacity of 0.1 m ³ / min to 1.28 m ³ / min,
3. The circulating air flow rate 24 by the auxiliary fan 26 is set to 1 m ³ / min to 2.5 m ³ / min,
4). The moisture content by the humidifier 22 is 0.4 kg / hr or less,
5). The relative humidity in the clean booth, that is, the space 16 is maintained at 45% RH or more and 65% RH or less.

  Thereby, the relative humidity effective for the inactivation of the influenza virus can be maintained and an appropriate negative pressure can be maintained, and the noise problem caused by the large air flow rate without setting a large air flow rate to the blower 20 Thus, it is possible to provide an infection spread prevention booth that can comfortably accommodate a patient without causing any problems.

Regarding the noise problem, in the conventional blower of the negative pressure isolation booth described above, an air flow rate of 3.3 m ³ / min was set, and a noise value of 40 dB was measured. On the other hand, at the infection spread prevention booth 10, only a noise value of 26 dB was measured, and it was possible to achieve significant silence.

  In addition, the infection spread prevention booth 10 according to the present invention exhibits a more excellent effect in the winter when air is easily dried.

  As described above, the example in which the infection spread prevention booth 10 is used for influenza virus has been described. However, it is said that there are more than 200 viruses causing colds, and in the winter, coronaviruses and rhinoviruses become active in addition to influenza viruses (though distinct from colds). Like the influenza virus, these viruses are also covered with an envelope containing lipids. When the virus with this structure floats in the air, it is difficult to inactivate it in the winter environment of low temperature and low humidity, and the infectivity titer is maintained for a long time. On the other hand, adenoviruses, echoviruses (enteroviruses), coxsackieviruses, etc. are active in summer, which is a hot and humid environment (other human metapneumoviruses (from March to June), etc.). These viruses do not have an envelope membrane, and when suspended in the air, all of them are not easily inactivated in a hot and humid summer environment and maintain their infectious titer for a long time.

  The infection spread prevention booth 10 according to the present invention is not only inactivated by humidification of a virus having an envelope film such as influenza virus, but also has no envelope film and floats in the air. In addition to or instead of the humidifier 22, an air conditioner having a drier or humidification, drying, and temperature adjustment function in order to enable inactivation against viruses that are difficult to deactivate and maintain an infectious value for a long time. The machine can be arranged.

  Instead of the fastener 18d of the enclosure 18, as shown in FIGS. 10 and 11, a permanent magnet 38 is fixed or embedded in, for example, both vertical edges of one side wall portion 18b, and the corresponding frame 14 is obtained by the magnetic force of the permanent magnet. Both vertical edges of the side wall portion 18b can be adsorbed and held on the column portion 14a. In this case, at least the column part 14a of the frame body 14 needs to be comprised with a magnetic body, and it is desirable for the column part 14a to have a rectangular cross-sectional shape. Further, in this case, as shown in FIG. 11, an extension portion 18f wound around the column portion 14a is provided on the vertical edge of each end wall portion 18c adjacent to both vertical edges where the permanent magnets 38 are provided. The extended end of the end portion can be fixed to the vertical edge of the end wall portion 18c with, for example, Velcro (registered trademark) 18g.

  Further, as shown in FIGS. 12 (a) and 12 (b), one side wall portion 18b is divided along a dividing line that runs in the vertical direction, and permanent magnets 38 are attached to both of the cut edges. It is possible to form an entrance that can be opened and closed by the magnetic force of the permanent magnet 38 arranged along each cutting edge so that the different magnetic poles face each other.

  Also in the example shown in FIG. 12, a fastener 18 d can be applied instead of the permanent magnet 38.

The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, the lower edge of the peripheral wall portion (18b, 18c) of the enclosure 18 is in close contact with the floor, and instead of the above-described gap, for example, an end wall portion on the opposite side to the one end wall portion 18c where the blower 20 is installed An opening of about 100 cm ³ can be formed in 18c as an air intake.

10 infection spread prevention booth 12 bed 14 frame 16 space (clean booth space)
18 Enclosure 20 Blower 22 Humidifier 24 Circulating Air Flow 26 Auxiliary Fan

Claims (5)

An enclosure for forming a clean booth covering the whole bed arranged in the room, a blower for purifying the air in the clean booth and discharging it outside the clean booth, and the clean booth The clean booth capacity formed by the enclosure includes an auxiliary fan for generating an air circulation flow in the clean booth and a humidifier for adjusting the humidity in the clean booth. 6 m ³ or more and 15 m ³ or less, the enclosure is substantially formed with an air intake of approximately 100 cm ² , and the blower blows air of 0.1 m ³ / min or more and 1.28 m ³ / min or less. operated at capacity, the circulating air air volume by the auxiliary fan, 1 m 3 ^/ min or more and is at 2.5 m 3 ^/ min or less, the humidification water content by the humidifier 0.4 kg / hr or less , And the humidifier by spread prevention booth, wherein said the relative humidity of the clean booth is maintained below RH or more and 65% RH 45%.   The booth according to claim 1, wherein the circulating air flow by the auxiliary fan eliminates uneven humidity in the clean booth.   The booth according to claim 1, wherein the humidifier is a steam humidifier.   The enclosure has a rectangular top portion that covers the top of the bed and a peripheral wall portion that hangs down from the top portion of the top portion to the floor of the room, and the air is formed by a gap between the lower edge of the peripheral wall portion and the floor. The booth according to claim 1, wherein an intake is formed.   The booth according to claim 1, wherein a quasi-HEPA or HEPA filter for air purification is attached to the blower.

Images