JP2000320872A - Clean room - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently conduct supply of clean air into both a positive pressure room and a negative pressure room and to smoothly conduct a series of dispensing operation to be executed in a clean environment, by forming one clean room with one system of an air circulating facility and dividing the room into the positive pressure room and the negative pressure room. SOLUTION: The clean room comprises a negative pressure room adjacent to a positive pressure room, an air channel for allowing falling of the air in the positive pressure room in the negative pressure room, a safety cabinet 10 installed in the negative pressure room, and an exhaust duct 34 having an exhaust fan 30 for forcibly exhausting the air in the negative pressure room out of the clean room. In this case, an exhaust port 34 of the cabinet 20 is connected to the duct 34 through a thimble flange 35 having an opening 36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clean room used for preparing a medicine in a clean environment in a medical facility such as a hospital or a drug research facility, and more particularly, to a clean room.
The present invention relates to a clean room in which a positive pressure chamber and a negative pressure chamber for different purposes are provided side by side, whereby the temperature and humidity of air in both chambers can be efficiently adjusted and purified by a single air circulation system.

[0002]

2. Description of the Related Art In medical facilities and drug research facilities,
Class 10 so that dispensing work can be performed in a clean environment
A clean room capable of realizing a cleanliness of about 0 to 10,000 is provided. In a clean room used for ordinary dispensing work, the air pressure in the room is often maintained at a positive pressure so that bacteria, dust and the like outside the room do not enter the room.

As a means for maintaining the air pressure in the clean room at a positive pressure, a method is generally employed in which air in the air circulation system is always introduced in addition to simply purifying the air in the room. . When outside air is added to the circulating air, the amount of air supplied from the air circulation system into the clean room increases, and becomes larger than the amount of air discharged from the room and returned to the air circulation system. Is maintained at a positive pressure.

[0004] In some facilities, in addition to the above-described positive pressure clean room, a clean room configured to maintain the indoor air pressure at a negative pressure may be provided. As a standard configuration example of the negative pressure clean room, as shown in FIG. 4, the indoor air is circulated while introducing outside air from the outside air intake 116, and the air conditioner 11 is used.
4, an air circulation system 113 for controlling the temperature and humidity and for cleaning by the clean unit 111 and supplying clean air into the negative pressure clean room 103.
By operating the exhaust fan 202, the exhaust port 2
01 and an exhaust system 204 capable of forcibly exhausting indoor air to the outside via an exhaust duct 203. There has been known an apparatus in which the amount of air forcedly discharged from a room is increased so that the indoor air pressure is maintained at a negative pressure.

[0005] In a negative pressure clean room, it is possible to avoid a situation in which room air leaks out of a room or the like to the outside, so that dangerous chemicals that may adversely affect the surrounding environment if leaked out of the room are removed. Suitable for handling. However, as mentioned above, the air in the room is exhausted outside by the exhaust system,
A negative pressure clean room used for handling dangerous chemicals or the like is usually provided with an air purifying means such as a HEPA filter in an exhaust system, and purifies room air that may have been contaminated and then discharges the air to the outside. It is configured as follows.

When dispensing a dangerous drug, it is necessary to ensure not only the surrounding environment but also the safety of the operator who performs the dispensing operation. Therefore, as shown in FIG. In many cases, a safe safety cabinet 110 is installed.

Here, the structure and operation of the safety cabinet 110 shown in FIG. 5 will be briefly described. The safety cabinet 110 is a device for safely handling chemicals, poisons, bacteria, and the like that may have a bad influence on workers and the surrounding environment. 122 are formed.

An air circulation path 131 is provided below the bottom plate 127 and on the back surface of the back plate 128. When the internal fan 121 provided at the end of the air circulation path 131 is operated, the work chamber 122 is closed. Air is sucked in from the small holes 129 provided in the bottom plate 127, reaches the internal fan 121 through the air circulation path 131, and is sent into the upper chamber 132 provided in front of the outlet of the internal fan 121. The air sent into the upper chamber 132 is supplied to the lower filter 126.
After the cleaning (dust removal and sterilization), it is supplied to the working chamber 122 again.

[0009] However, the upper fan 132
All of the air sent into the lower filter 126
Instead of being circulated through, a part thereof is cleaned by the upper filter 125 and then discharged to the outside of the safety cabinet 110 through the exhaust port 124.

As described above, when the internal fan 121 is operating, the internal air circulates and is repeatedly cleaned, so that the desired cleanliness is maintained in the work chamber 122 and the internal air is removed. Since a part of the air is exhausted from the exhaust port 124 to the outside, a loss occurs in the internal pressure, and the air pressure in the working chamber 122 becomes negative with respect to the outside of the apparatus.

Therefore, the same amount of air discharged from the exhaust port 124 to the outside of the apparatus as the air is discharged from the front opening 1 formed by sliding the shutter 123 upward.
33 always flows into the working chamber 122,
It is possible to prevent a situation in which internal air that may have been contaminated by performing the work flows out of the front opening 133 into the clean room, thereby ensuring the safety of workers. .

The exhaust port 12 of the safety cabinet 110
4 is connected to an exhaust duct 134 that communicates with the outside through a wall hole 120 of the clean room, and an exhaust port 124
The air discharged from the outside of the safety cabinet 110 is sucked by the exhaust fan 130 provided in the exhaust duct 134, and is discharged to the outside of the clean room through the exhaust duct 134. The air discharged to the outside through the exhaust duct 134 has already been purified by the upper filter 125 of the safety cabinet 110 as described above,
Even if the drugs and bacteria handled in 10 are powerful drugs and pathogenic bacteria, they will not adversely affect the surrounding environment,
Safety has been ensured.

[0013]

[0005] Recently, pharmacotherapy has been widely adopted for the treatment of cancer and the like. Demand for drugs that require careful handling, such as neoplastic drugs, is growing rapidly. For this reason, the demand for the negative pressure clean room as described above has been increasing, but in addition to the positive pressure clean room for performing normal dispensing work, if a negative pressure clean room is to be separately constructed, the work efficiency is also increased. There is also an economic problem.

For example, a clean room is often provided with an anterior chamber equipped with a sterilizing / cleaning device and an air shower device. Before entering the clean room, an operator uses the device to preliminarily use the device. By cleaning, it is possible to minimize the possibility of bacteria and dust being brought into the room by the operator himself.However, the positive pressure clean room and the negative pressure clean room are constructed separately. In such a case, there is a problem that it is difficult to perform the operation smoothly when the operator needs to move between the clean rooms.

There are the following problems economically. For example, a positive-pressure clean room and a negative-pressure clean room share a common point in that an air circulation system that cleans indoor air while introducing outside air is common. If shared by both clean rooms, that is, if a single air circulation system can supply clean air to both clean rooms, the cost of equipment construction can be reduced, but the positive pressure clean room and negative pressure clean room Then, naturally, since the air pressure in the room is different, it is difficult to configure so that one air circulation system can be shared by both clean rooms.

Specifically, in order to realize such a system, it becomes necessary to distribute the amount of clean air supplied to each clean room at an appropriate ratio.
Also, when the indoor air is sucked and returned to the air circulation system, it is necessary to calculate the appropriate amount of air to be collected from each clean room and adjust it appropriately. Inevitably, the system must be complicated, and on the contrary, the equipment cost and the cost of maintenance and the like increase.

Further, when the safety cabinet 110 as shown in FIG. 5 is installed in the negative pressure clean room, it is more difficult to configure the air circulation system so that it can be shared with the positive pressure clean room. It is. As shown in FIG. 4, when the safety cabinet 110 is installed in the negative pressure clean room 103,
This is because the amount of outside air taken into the air circulation system 113 from the outside air intake 116 is determined in consideration of the amount of air discharged outside the room when the safety cabinet 110 is operated. .

To explain this point in more detail, as described above, in the negative pressure clean room 103,
The amount of air that is forcibly exhausted outside by the exhaust system 204 is supplied from the outside air intake 116 to the air
The air pressure in the room is maintained at a negative pressure due to the difference between the amount of outside air to be taken into the inside 13 and the difference therebetween. Since a certain amount of indoor air is forcibly exhausted to the outside through the exhaust duct 134, the total amount of indoor air discharged when the safety cabinet 110 is in operation increases compared to when it is not in operation.

Therefore, if the amount of outside air taken into the air circulation system 113 from the outside air intake 116 is always constant irrespective of whether the safety cabinet 110 is operating or not, the air pressure in the room becomes constant.
Will fluctuate according to the operating status of the system. Fluctuation of the indoor air pressure is by no means desirable in performing a drug dispensing operation, and therefore, in order to avoid such a situation, a negative pressure clean room 103 as shown in FIG.
When the safety cabinet 110 is operated, the amount of outside air taken into the air circulation system 113 from the outside air intake 116 is increased in consideration of the amount of air exhausted outdoors due to the operation of the safety cabinet 110. The structure is such that the room is always kept at a constant air pressure.

The safety cabinet is installed in this way,
As described above, the configuration is such that the air circulation system can be shared between the negative pressure clean room that needs to adjust the amount of outside air to be introduced from the outside air intake and the positive pressure clean room that does not need such. Very difficult.

Therefore, at present, a facility for dispensing dangerous chemicals, which would otherwise need to be performed in a negative pressure clean room, is inevitably performed using a safety cabinet installed in the positive pressure clean room for economic reasons. There are also
If an accident occurs during pre-treatment before bringing the drug into the safety cabinet or during normal handling work, contaminated air can easily leak out of the room and cannot be recovered. Could develop into

The present invention solves the above problems and eliminates the necessity of separately constructing a positive pressure clean room and a negative pressure clean room having different uses and characteristics. And to divide the chamber into a positive pressure chamber and a negative pressure chamber, to supply clean air to both chambers efficiently, and to smoothly perform a series of dispensing operations to be performed in a clean environment. The purpose of the present invention is to provide a clean room in which a clean room can be provided.

[0023]

SUMMARY OF THE INVENTION In order to solve the above problems, a clean room according to the present invention is designed so that the indoor air pressure is maintained at a positive pressure, and the temperature of the room is controlled by an air circulation system having air conditioning means and air cleaning means. Humidity and a negative pressure chamber in which the air pressure in the room is maintained at a negative pressure are provided adjacent to the positive pressure chamber in which the cleanliness is maintained, and between the positive pressure chamber and the negative pressure chamber. An air flow passage that allows air in the positive pressure chamber to flow down to the negative pressure chamber and that can change the opening area thereof; a safety cabinet installed in the negative pressure chamber; An exhaust duct provided with a fan for being introduced into the pressure chamber and forcibly discharging air in the negative pressure chamber to the outside of the clean room, wherein an exhaust port of the safety cabinet and the exhaust duct are opened. Have a department It is characterized in that it is connected via a thimble flanges.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a clean room 1 according to the present invention, and FIG.
FIG. 2 is a system diagram of an air circulation system used in the first embodiment.

First, an outline of the clean room 1 in the present embodiment will be described. In FIG. 1, reference numeral 2 denotes a positive pressure chamber configured to maintain the indoor air pressure at a positive pressure.
Adjacent to the positive pressure chamber 2 is a negative pressure chamber 3 configured to maintain the air pressure in the room at a negative pressure. In the positive pressure chamber 2, the temperature and humidity of the room are adjusted by an air circulation system 13 (see FIG. 2) having an air conditioning unit and an air cleaning unit, and the room is maintained at a desired degree of cleanliness. I have.

Further, a door 5 is provided on a partition wall 4 separating the positive pressure chamber 2 and the negative pressure chamber 3 so that an operator can freely and easily move between the two chambers. A series of operations to be performed can be performed smoothly. The partition wall 4 is provided with an air flow path 6 that allows the air in the positive pressure chamber 2 to flow down to the negative pressure chamber 3.
Since the air in the positive pressure chamber 2 constantly flows into the negative pressure chamber 3 from here, the room temperature, humidity, and cleanness in the negative pressure chamber 3 are equal to (or similar to) the positive pressure chamber 2. The degree is maintained.

In FIG. 1, reference numeral 7 denotes a front room in which an operator prepares to enter the clean room 1 (the positive pressure chamber 2 and the negative pressure chamber 3). The front room 7 is provided with an air shower device 8 and an aseptic hand washing device 9. An operator who wants to enter the clean room 1 changes into a dust-free garment or the like in the front room 7, and then the air shower device 8 and aseptic hand washing equipment 9
Can be used to remove dust and sterilize before entering the room, thereby preventing dust and various bacteria from being brought into the clean room 1 by the operator himself.

Next, the air circulation system 13 used in the clean room 1 will be described. As shown in FIG. 2, the air circulation system 13 includes a circulation air inlet 1.
2 (12a to 12c), an outside air intake 16, an air conditioner 14 as air conditioning means, a clean unit 11 as air cleaning means, and a duct 15 (15a to 15e).

In the present embodiment, as shown in FIG. 2, the air conditioner 14 and the clean unit 11 are configured so as to be included in the air circulation system 13 as devices independent of each other. It is not necessary to be configured as a separate and independent device, and a single device having both a function as an air conditioner and a function as an air purifier (for example, an air conditioner with a built-in high-performance filter,
Alternatively, it may be included in the air circulation system 13 as a clean unit having an air conditioning function).

The operation of purifying the air in the positive pressure chamber 2 by the air circulation system 13 having the above configuration will be described. First, air in the positive pressure chamber 2 is sucked from the circulating air suction port 12 (see FIG. 1) provided at a corner of the positive pressure chamber 2, and the sucked air (return air) is supplied to the duct 1.
The air is sent to the air conditioner 14 via 5a to 15c. Air conditioner 1
4 is for taking in return air,
A required amount of outside air is introduced, and they are heated or cooled to adjust the temperature and, if necessary, the humidity. The air (conditioned air) whose temperature and humidity have been adjusted is sent from the air conditioner 14 to the clean unit 1 via a duct 15e.
Sent to 1. The clean unit 11 can clean (dust and sterilize) the conditioned air with a built-in high-performance filter (HEPA filter) and supply the purified air (clean air) into the positive pressure chamber 2. I have.

In this embodiment, the clean unit 11 is installed at the center of the ceiling of the positive pressure chamber 2 (see FIG. 1), and is configured such that the outlet of the clean air opens downward. . Therefore, the clean air is blown from the clean unit 11 at the center of the ceiling toward the center of the floor surface or onto the workbench disposed there.
Then, the clean air reaching the floor surface or the surface of the worktable arranged there is gently sucked by the circulating air suction port 12 installed at the corner of the positive pressure chamber 2 to generate the radial airflow 18. It is formed and finally sucked again from the circulating air suction port 12 and circulates in the air circulation system 13 and the positive pressure chamber 2. As described above, the air circulation system 13 constantly circulates indoor air, and repeatedly performs adjustment and cleaning of temperature and humidity, thereby achieving desired temperature, humidity, and cleanliness in the positive pressure chamber 2. .

Next, the negative pressure chamber 3 provided adjacent to the positive pressure chamber 2 will be described. As shown in FIG. 1, a safety cabinet 10 is installed in the negative pressure chamber 3. This safety cabinet 10 has the same basic structure as the safety cabinet 110 shown in FIG. 5 as a conventional example, and therefore details are omitted, but FIG. 3 (along the AA line of the safety cabinet 10 shown in FIG. 1). As shown in the cross-sectional view), the safety cabinet 110 differs from the conventional safety cabinet 110 in that the exhaust port 24 and the exhaust duct 34 are connected via a thimble flange 35.

The thimble flange 35 has an opening 36.
Is formed, and the air in the negative pressure chamber 3 is blown through the opening 3.
6 and the exhaust duct 34 of the safety cabinet 10
It can be discharged to the outside of the room. Therefore,
The exhaust system can be simplified.

That is, in a conventional negative pressure clean room having a safety cabinet, as shown in FIG. 4, in addition to the exhaust system 204 for maintaining the room air pressure at a negative pressure, the air was discharged from the safety cabinet 110. Although an exhaust duct 134 for discharging air to the outside of the room is provided, and two exhaust systems coexist, in the present embodiment, as described above, through the thimble flange 35 having the opening 36 as described above. Exhaust port 2 of safety cabinet 10
4 and the exhaust duct 34 are connected, so that not only the air exhausted from the safety cabinet 10 but also the air in the negative pressure chamber 3 is exhausted from the exhaust duct 34 of the safety cabinet 10. Therefore, the room air pressure can be maintained at a negative pressure without providing the exhaust system 204 as shown in FIG.

In a conventional negative pressure clean room having a safety cabinet, while the safety cabinet is in operation, the amount of outside air to be introduced from the outside air intake is determined in consideration of the amount of air discharged from the safety cabinet. Although it was configured to increase, in the present embodiment, a configuration that increases the amount of outside air introduced during operation of the safety cabinet is unnecessary, regardless of whether or not the safety cabinet is operating, The air pressure in the room can always be kept constant.

This will be described in more detail with reference to FIG. First, assuming that the amount of air that is forcibly discharged outside the room by operating the exhaust fan 30 is R, the amount of room air sucked from the opening 36 of the thimble flange 35 when the safety cabinet 10 is not operated. The quantity is
It is the same amount as R. On the other hand, when the amount of air discharged from the safety cabinet 10 during the operation of the safety cabinet 10 is S, the amount of room air sucked from the opening 36 of the thimble flange 35 is “RS”, and However, when the safety cabinet 10 is in operation, the same amount of indoor air as S is sucked into the work room 22 from the front opening 33 of the safety cabinet 10 when the safety cabinet 10 is in operation. The amount of room air discharged outside through the exhaust duct 34 is “RS−S (= R)”.
As a result, the total amount of indoor air discharged to the outside is always constant regardless of the operation state of the safety cabinet 10, and therefore, the air pressure in the room is always kept constant.

As described above, in the present embodiment, as shown in FIG. 4, the exhaust system 204 for maintaining the indoor air pressure at a negative pressure and the amount of outside air introduced when the safety cabinet is operated are increased. No special configuration is required. Therefore, the exhaust system is simplified, and equipment costs and maintenance costs can be saved.

In this embodiment, the exhaust fan 3
Although 0 is provided at the end of the outdoor exhaust duct 34, the installation position is not limited to this, and if indoor air can be exhausted to the outside, for example, indoors or inside a wall, etc. You may comprise so that it may be installed.

Further, any position of the exhaust duct 34,
Alternatively, near the upstream or downstream side of the exhaust fan 30,
It is preferable to provide a means for purifying exhaust air comprising a high-performance filter such as an EPA filter. In the conventional exhaust system of the safety cabinet, since only the safe air purified by the safety cabinet was exhausted, a cleaning means such as a filter was not necessary, but in the present embodiment, Since the air in the negative pressure chamber 3 is configured to be sucked through the opening 36 of the thimble flange 35 and discharged to the outside through the exhaust duct 34, dangerous chemicals are handled in the negative pressure chamber 3. This is because, if the indoor air is contaminated by an accident or the like during the operation, the contaminated air may be directly discharged to the outside.

The clean room 1 of this embodiment is constituted by the positive pressure chamber 2 and the negative pressure chamber 3 as described above. By adjusting the amount and the amount of air discharged from the exhaust duct 34 of the safety cabinet 10 to the outside as follows, the air pressure of the positive pressure chamber 2 is changed to the positive pressure, and the air pressure of the negative pressure chamber 3 is changed. Negative pressure can be maintained.

First, as described above, the positive pressure chamber 2 is configured so that room air is sucked from the circulating air suction port 12 disposed at the corner, and is provided between the positive pressure chamber 2 and the negative pressure chamber 3. The room air flows down from the air passage 6 of the partition wall 4 to the negative pressure chamber 3, and the amount of return air returned from the circulating air suction port 12 to the air circulation system 13 is represented by B. Assuming that the amount of air flowing down from 6 to the negative pressure chamber 3 is C, the total amount of air discharged from the positive pressure chamber 2 is “B + C”.
On the other hand, assuming that the amount of outside air introduced from outside air inlet 16 is D, the total amount of clean air supplied from clean unit 11 into positive pressure chamber 2 is “B + D”. If more air is supplied to the room than the amount of air discharged from the room,
Since the indoor air pressure can be maintained at a positive pressure, "B +
D> B + C (= “D> C”) ”, that is, if more outside air than air flowing down from the air flow path 6 to the negative pressure chamber 3 is introduced from the outside air intake 16, The air pressure in the positive pressure chamber 2 can be maintained at a positive pressure, so that bacteria, dust, and the like outside the room can be suitably prevented from entering the positive pressure chamber 2.

On the other hand, as described above, the negative pressure chamber 3 always discharges a constant amount (R) of air to the outside regardless of whether the safety cabinet 10 is operating. , "R>C", that is, if more air than the air supplied from the air flow path 6 into the negative pressure chamber 3 is discharged to the outside, the air pressure in the negative pressure chamber 3 is reduced. Negative pressure can be maintained, and a situation in which room air leaks to the outside from a gap in a room or the like can be avoided.

In this embodiment, the air passage 6
The opening area can be changed, so that the amount of air flowing from the positive pressure chamber 2 to the negative pressure chamber 3 can be adjusted. As a result, the air pressure in both chambers can be freely adjusted. It can be adjusted.

Further, in the present embodiment, of the four corners of the positive pressure chamber 2, three of the corners are
(12a to 12c) are arranged and the air flow path 6 is provided at the remaining one corner, so that the air is blown out from the clean unit 11 at the center of the ceiling of the positive pressure chamber 2 toward the center of the floor. The clean air is sucked by the circulating air suction port 12 and the air flow path 6, and radial air flows 18, 19 are formed toward the four corners of the room.

In a turbulent-type clean room, air currents may be stagnant at the corners of the room, which often causes deterioration in circulation efficiency and, in turn, purification efficiency. As described above, since the radial airflow 18 is formed from the center of the room to the four corners, the airflow does not stagnate in the positive pressure chamber 2 and an airflow close to a laminar flow is formed. can do.

Also, ducts 15a to 15c for returning air from the circulating air suction ports 12a to 12c to the air conditioner 14 are provided.
Each pressure damper is provided in each of the positive pressure chambers 2 (see FIG. 2) so that the opening area of the air flow path 6 can be adjusted and the pressure dampers can be operated to adjust the flow rate of air in each of them. Inside, a balanced ideal airflow can be formed.

[0047]

As described above, the clean room according to the present invention is provided with a negative pressure chamber adjacent to the positive pressure chamber so that the air in the positive pressure chamber flows down into the negative pressure chamber. By connecting the safety cabinet installed in the negative pressure chamber and the exhaust duct via a thimble flange, it is possible to efficiently supply clean air to both chambers with different applications and characteristics with only one air circulation system. A layout that can be realized can be realized.

This makes it possible to smoothly perform a series of dispensing operations to be performed over both the rooms where the desired cleanliness is maintained, and not only for the air circulation system but also for ancillary equipment such as an air shower device. Because it can be shared by both rooms and the exhaust system can be simplified, it is possible to expect the excellent effect of saving the cost required for equipment construction and maintenance, and the energy required for operation. It is.

Further, by changing the opening area of the air passage, the flow rate of the air flowing from the positive pressure chamber to the negative pressure chamber can be adjusted, and the air pressure in both chambers can be adjusted. By using the thimble flange, it is possible to expect an effect that the air pressure in the negative pressure chamber can always be kept constant regardless of whether the safety cabinet is in operation or not.

[Brief description of the drawings]

FIG. 1 is a plan view of a clean room 1 according to the present invention.

FIG. 2 is a system diagram of an air circulation system 13 used in the clean room 1 of FIG.

FIG. 3 is a sectional view of the safety cabinet 10 shown in FIG. 1 taken along the line AA.

FIG. 4 is a system diagram showing a configuration example of a conventional negative pressure clean room 103.

FIG. 5 is a cross-sectional view of a conventional safety cabinet 110.

[Explanation of symbols]

 1: clean room, 2: positive pressure chamber, 3: negative pressure chamber, 4: partition wall, 5: door, 6: air passage, 7: front room, 8: air shower device, 9: aseptic hand washing device, 10, 110: Safety cabinet, 11, 111: Clean unit, 12, 112: Circulating air inlet, 13, 113: Air circulation system, 14, 114: Air conditioner, 15, 115: Duct, 16, 116: Outside air intake, 18, 19: radial air flow, 20, 120: wall hole, 21, 121: internal fan, 22, 122: work room, 23, 123: shutter, 24, 124: exhaust port, 25, 125: upper filter, 26 , 126: Lower filter, 27, 127: Bottom plate, 28, 128: Back plate, 29, 129: Small hole, 30, 130: Exhaust fan, 31, 131: Air circulation path, 32, 1 2: upper chamber, 33, 133: front opening, 34, 134: exhaust duct, 35: thimble flange, 36: opening, 103: negative pressure clean room, 201: exhaust port, 202: exhaust fan, 203: exhaust duct 204: Exhaust system

Claims (1)

[Claims] An indoor air pressure is maintained at a positive pressure, and an indoor air temperature and humidity and a cleanliness level are maintained by an air circulation system having an air-conditioning means and an air cleaning means. A clean room provided with a negative pressure chamber in which air pressure is maintained at a negative pressure, provided between the positive pressure chamber and the negative pressure chamber, wherein air in the positive pressure chamber flows down to the negative pressure chamber. An air flow path that permits and changes the opening area thereof, a safety cabinet installed in the negative pressure chamber, and one end of which is introduced into the negative pressure chamber and forcibly removes air in the negative pressure chamber. An exhaust duct provided with an exhaust fan for discharging to the outside of the safety cabinet, the exhaust port of the safety cabinet and the exhaust duct,
A clean room, which is connected through a thimble flange having an opening.