JPH078544A - Sterilizing tank for medical supplies - Google Patents

Abstract

PURPOSE:To provide a sterilizing tank for medical supplies capable of preventing a sterilization failure and extremely efficiently and effectively sterilizing a material to be sterilized in formaldehyde gas sterilization using, as gas supplying source, a granular powder of plaster of Paris impregnated with formalin. CONSTITUTION:In a sterilizing tank for medical supplies, a gas generating source of a granular powder 14 of plaster of Paris impregnated with formalin is replaceably arranged in a transparent box 12 surrounded in four sides and having a door 20 for opening and closing a part, and a heater 2, a temperature sensor 3, and an internal circulating blower 1 are similarly installed in the transparent box 12. A temperature regulator 11 having the detection input of the temperature sensor 3 is connected to the heater 2, and the transparent box 12 is kept at a specific temperature by the control of the temperature regulator 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sterilization tank for medical products which uses formaldehyde gas used in medical facilities.

[0002]

2. Description of the Related Art In the medical field, one of the methods for sterilizing medical items such as surgical clothes, clothes and surgical instruments is a gas sterilization method using a sterilization tank. The gas sterilization method using a sterilization tank is
The object to be sterilized is put in a container that can be closed, and gas having sterilizing ability is generated in the container for sterilization. This sterilization method has an advantage of having a sterilizing effect at a relatively low temperature close to room temperature, and formaldehyde gas is often used as a gas having sterilizing ability.

In formaldehyde gas sterilization treatment, a method of heating formalin for fumigation, a method of heating solid paraformaldehyde, a method of using granular powder obtained by impregnating calcined gypsum with formalin, etc. are used as a gas generating source. It is used. Among them, in medical facilities, a method of using granular powder in which calcined gypsum is impregnated with formalin is prevalent.

In a sterilization tank for medical products using a granular powder obtained by impregnating calcined gypsum with formalin, the substance to be sterilized is stored on a shelf of a desiccator made of plastic, and the granular powder is put in a petri dish. Install it at the bottom of the desiccator and close the door. After that, in the indoor environment from 12 hours to 48
The method of leaving it naturally for a time is generally used.

[0005]

Since the temperature inside the desiccator is not regulated in the above-mentioned sterilization tank for medical products, formalin is added to calcined gypsum in an environment where the indoor temperature is 15 ° C or lower, such as in winter. Sufficient formaldehyde gas may not be generated from the impregnated granular powder, which causes sterilization failure. In addition, it takes a long time to obtain a sterilized state because it takes time to generate sufficient formaldehyde gas even in an environment of 15 ° C. or higher.

The present invention has been made to solve the above-mentioned problems, and in a sterilization tank for medical products which uses a granular powder obtained by impregnating formalin in calcined gypsum, which is routinely used in medical facilities, as a gas supply source, An object of the present invention is to provide a sterilization tank for medical products that prevents sterilization defects and enhances the sterilization effect.

[0007]

A sterilization tank for medical products according to the present invention, which has been made to achieve the above object, has four sides surrounded by a door 20 for opening and closing a part thereof as shown in FIG. A gas generating source of the granular powder 14 in which formalin is impregnated in calcined gypsum is replaceably arranged in the transparent housing 12, and a heater 2 for heating and a temperature sensor 3 are also provided in the transparent housing 12. Further, a temperature controller 11 having an internal circulation blower 1 and having the temperature sensor 3 as a detection input is connected to the heating heater 2. Under the control of the temperature controller 11, the temperature inside the transparent housing 12 is kept constant. Kept in.

[0008]

As shown in FIG. 1, the heater 2 for heating supplements the heat radiated from the surface of the desiccator 12 to sterilize the object to be sterilized in the sterilizing tank for medical products of the present invention, thereby keeping the temperature inside the tank. Raise to room temperature or above. The circulation blower 1 makes the temperature in the desiccator 12 uniform and disperses the formaldehyde gas to eliminate the unevenness of concentration and make the sterilizing effect uniform. The temperature controller 11 measures the temperature inside the desiccator 12 with the temperature sensor 3, and compares the measured temperature with the preset temperature by the control circuit 30 (see FIG. 2). When the driving of the heating heater 2 is controlled based on the comparison result, the temperature inside the tank and the preset temperature become the same.

[0009]

EXAMPLES Examples of the present invention will be described below. FIG. 1 is a sketch of a sterilization tank for medical products of the present invention.

The sterilization tank for medical products shown in FIG. 1 is a 40-liter acrylic box 12, which is an acrylic box 1.
Three shelves 17, 18 and 19 for accommodating items to be sterilized such as surgical clothes, clothes, instruments and the like are attached to the upper part of the inside of 2. A heater 2 for heating 600 W is provided below the shelves 17, 18 and 19 and in the center of the bottom of the acrylic box 12. 4 cm above the heater 2 for heating (2 to
A temperature sensor 3 (platinum resistance thermometer 100Ω) inserted from the side of the box 12 is provided at a position (5 cm is suitable). Further, the acrylic box 12 is provided with an internal circulation blower 1 behind the heating heater 2, and a gas generating source of the granular powder 14 in which formalin is impregnated in calcined gypsum is placed next to the heating heater 2 in a petri dish. It is put in 15.

Below the heating heater 2, 3 mm is used to prevent the acrylic box 12 from being affected by heat.
The heating heater 2 is surrounded by the net-like cover 13 to prevent danger from directly coming into contact with the contents or the like.

The material of the box 12 is hard vinyl chloride, polycarbonate, ABS resin, polypropylene,
It may be polyamide, phenol resin, AS resin or the like. In particular, acrylic and polycarbonate are good in terms of strength and heat resistance, and are transparent, so that they can check the condition of the contents and the discoloration of the indicator bacterium, and thus are most suitable. In addition, the size of the box 12 may be any size, but an appropriate size is 30 liters to 200 liters.
It is a liter.

A control unit 4 is attached to the outer side of the acrylic box 12, and the front of the control unit 4 is
The timer power indicator lamp 5, the temperature controller power indicator lamp 8 and the excessive temperature rise prevention device operation indicator lamp 10 are displayed so as to be visible, and a timer power switch 6 and a temperature controller power switch 9 are provided. . Further, the controller 4 has a temperature controller 11 and a timer 7 built therein.

FIG. 2 is a control block diagram of the temperature controller 11 in the sterilization tank for medical products to which the present invention is applied. As shown in the figure, the heater 2 is connected to the heater drive circuit 31, and the heater drive circuit 31 and the temperature sensor 3 are connected to the control circuit 30.

The normal operation of the sterilization tank for medical products in a medical facility will be described below. First, as shown in FIG. 1, a surgical gown is placed on the shelves 17, 18, and 19 and the door 20 is closed. Set the time with timer 7 and box 1
The temperature controller 11 is set to the desired temperature in 2, and the timer power switch 6 and the temperature controller power switch 9 are turned on. Then, the circulation blower 1 is operated, the temperature sensor 3 measures the temperature in the box 12, and the measured temperature is compared with the set temperature in the control circuit 30 (see FIG. 2). When the measured temperature is lower than the set temperature, the heater driving circuit 31 turns on the heater 2. After the measured temperature in the box 12 becomes the same as the set temperature, the current of the heater 2 is adjusted so that the box 12 is kept at the set temperature.

Using the above sterilization tank for medical products, performance tests 1 to 5 were carried out to measure the formaldehyde gas concentration in the tank and the killed state of bacteria when the sterilization treatment was carried out at five kinds of set temperatures. Further, using an acrylic box without a heating device, as Comparative Tests 1 to 3, the concentration of formaldehyde gas in the tank and the killed state of the bacteria were measured when three kinds of sterilization treatments were performed at room temperature.

Efgen (manufactured by Tateyama Chemical Co., Ltd.) was used for the granular powder obtained by impregnating formalin in calcined gypsum, and a commercially available biological indicator (ATTEST: used for ethylene oxide gas sterilization) was used as the indicator bacterium. 3M) was used. The formaldehyde gas concentration was measured by gas chromatography (GC-380: manufactured by GL Science). After use, the Efgen and biological indicators can be replaced.

Performance test 1 The temperature inside the box 12 was adjusted to 15 ° C., and the three shelves 17
・ Place a biological indicator on 18 ・ 19.
After 11.5 parts by weight of Efgen is placed in a Petri dish 15 and placed on the bottom of the box 12 so that the formaldehyde concentration in the box 12 is about 3 vol%, the door 20 is closed. Heating heater 2
Power on and set the temperature inside the box 12 to 40 ° C.

In this state, the maximum gas concentration when sterilized, the time to reach the maximum gas concentration, and the bactericidal time of the biological indicator were measured. As a result, the maximum gas concentration was 3500 ppm, the maximum gas concentration was reached in 3 hours, and the biological indicator died in 2 hours.
The results are shown in Table 1.

Performance Test 2 The same operation as in Performance Test 1 was performed, and the temperature inside the box 12 was adjusted to 3
The temperature was set to 5 ° C., and the maximum gas concentration when sterilized in this state, the time to reach the maximum gas concentration, and the bacterial killing time of the biological indicator were measured. As a result, the maximum gas concentration was 3300 ppm, the maximum gas concentration was reached in 4 hours, and the biological indicator died in 3 hours.
The results are shown in Table 1.

Performance Test 3 The same operation as in Performance Test 1 was performed, and the temperature inside the box 12 was adjusted to 3
The temperature was set to 0 ° C., and the maximum gas concentration when sterilized in this state, the time to reach the maximum gas concentration, and the bacterial killing time of the biological indicator were measured. As a result, the maximum gas concentration was 2900 ppm, the maximum gas concentration was reached in 5 hours, and the biological indicator died in 4 hours.
The results are shown in Table 1.

Performance Test 4 The same operation as in Performance Test 1 was performed, and the temperature inside the box 12 was adjusted to 2
The temperature was set to 5 ° C., and the maximum gas concentration when sterilized in this state, the time to reach the maximum gas concentration, and the bacterial killing time of the biological indicator were measured. As a result, the maximum gas concentration was 2500 ppm, the maximum gas concentration was reached in 6 hours, and the biological indicator died in 7 hours.
The results are shown in Table 1.

Performance Test 5 The same operation as in Performance Test 1 was performed, and the temperature inside the box 12 was adjusted to 2
The temperature was set to 0 ° C., and the maximum gas concentration when sterilized in this state, the time to reach the maximum gas concentration, and the bacterial killing time of the biological indicator were measured. As a result, the maximum gas concentration was 1800 ppm, the maximum gas concentration was reached in 9 hours, and the biological indicator died in 12 hours. The results are shown in Table 1.

Comparative Test 1 An acrylic box 12 is installed in a room controlled at 20 ° C. A biological indicator is placed on the three shelves 17, 18 and 19 inside the box 12. Efgen 11. so that the formaldehyde concentration in the box 12 is about 3 vol%.
After placing 5 parts by weight on the bottom of the container 12 in the Petri dish 15,
Close the door 20.

In this state, the maximum gas concentration when sterilized, the time to reach the maximum gas concentration, and the bactericidal time of the biological indicator were measured. As a result, the maximum gas concentration was 1500 ppm, the maximum gas concentration was reached in 15 hours, and the biological indicator died in 15 hours. The results are shown in Table 1.

Comparative Test 2 At room temperature of 15 ° C., the maximum gas concentration when sterilized by the same operation as in Comparative Test 1, the time to reach the maximum gas concentration, and the bacterial killing time of the biological indicator were measured. As a result, the maximum gas concentration was 1300ppm,
The maximum gas concentration was reached in 8 hours and the biological indicator died in 20 hours. The results are shown in Table 1.

Comparative Test 3 At room temperature of 10 ° C., the maximum gas concentration when sterilized by the same operation as in Comparative Test 1, the time required to reach the maximum gas concentration, and the bactericidal time of the biological indicator were measured. As a result, the maximum gas concentration was 600ppm,
Efficient generation of formaldehyde gas was not observed even after the lapse of time. Further, the biological indicator survived even after the sterilization treatment for 48 hours. The results are shown in Table 1.

[0028]

[Table 1]

[0029]

As described in detail above, the sterilization tank for medical products of the present invention uses formaldehyde gas, which is a granular powder obtained by impregnating formalin in calcined gypsum, which is commonly used in medical facilities. In sterilization, it is possible to prevent sterilization failure and sterilize the object to be sterilized extremely efficiently and effectively.

[Brief description of drawings]

FIG. 1 is a sketch of a sterilization tank for medical products to which the present invention is applied.

FIG. 2 is a control block diagram of a sterilization tank for medical products to which the present invention is applied.

[Explanation of symbols]

1 is a circulation blower, 2 is a heater for heating, 3 is a temperature sensor, 4 is a control unit, 5 is a timer power indicator light, 6
Is a timer power switch, 7 is a timer, 8 is a temperature controller power indicator light, 9 is a temperature controller power switch, 10 is an overheat prevention device operation indicator light, 11 is a temperature controller, 12 is a box, 13 is a mesh A cover, 14 is granular powder, 15 is a petri dish, 16 is a heat insulating material, 17/18/19 is a shelf, 20 is a door, 30 is a control circuit, and 31 is a heater drive circuit.

Claims (1)

[Claims] 1. A gas source of granular powder in which calcined gypsum is impregnated with formalin is exchangeably arranged in a transparent housing which is surrounded by four sides and a door for opening and closing a part of which is transparent. A heater for heating, a temperature sensor, and a blower for internal circulation are provided in a housing, and a temperature controller having the temperature sensor as a detection input is connected to the heater for heating, and is transparent under the control of the temperature controller. A sterilization tank for medical products, characterized in that the inside of the housing is kept at a constant temperature.