JP2013141506A - Sterilization device and sterilization method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sterilization device and a sterilization method that facilitate management.SOLUTION: The sterilization device includes: a gas supply device 12 which supplies hydrogen peroxide gas into a sealed space 100; a detector 13 which can detect concentration of the hydrogen peroxide gas in the sealed space 100 and humidity in the sealed space 100; storage means 41 of storing a threshold with which prescribed sterilization effects in the sealed space 100 are obtained; and control means 14 of calculating a first integrated value of variation in concentration of the hydrogen peroxide gas supplied into the sealed space 100 with an elapsed time and a second integrated value of variation in humidity in the sealed space 100 with the elapsed time, comparing the product of the calculated first integrated value and the second integrated value with the threshold, and determining that the prescribed sterilization effects are obtained in the sealed space 100 when the product of the first integrated value and the second integrated value is equal to or larger than the threshold.

Description

  The present invention relates to a sterilization apparatus and a sterilization method for sterilizing a sealed space using hydrogen peroxide gas.

  Conventionally, as a method for sterilizing an object such as a product or a device disposed in a sealed space or a sealed space, a technique for fumigating using formaldehyde has been known. However, the sterilization method using formaldehyde has problems such as an influence on the human body. Therefore, a sterilization method using hydrogen peroxide gas (Vapor Hydrogen Peroxide) with high safety and high productivity is known.

  As such a sterilization apparatus using hydrogen peroxide gas, the hydrogen peroxide gas is filled in the sealed space, and the sterilization is performed by destroying the DNA, cell wall or enzyme of microorganisms by the radicals of the hydrogen peroxide gas. Techniques are known (see, for example, Patent Document 1 and Patent Document 2).

  In addition, in order to sterilize the surface of the prefilled syringe enclosed in a packaging container made of a porous packaging material, the surface temperature of the prefilled syringe is controlled, and then another temperature and humidity are controlled to perform sterilization. Is also known (see, for example, Patent Document 3). Another known sterilization method is to rapidly increase the concentration of hydrogen peroxide vapor in the enclosed space and then remove the hydrogen peroxide vapor in the enclosed space when the concentration falls below a predetermined concentration. (For example, see Patent Document 4). In order to obtain higher bactericidal properties, a method of directly spraying a hydrogen peroxide solution on an object is also known.

JP 2006-320486 A JP 2005-143727 A JP 2010-57597 A JP 2005-31799 A

  The sterilization apparatus and sterilization method described above have the following problems. That is, in the sterilization method described above, management is performed by increasing the concentration of hydrogen peroxide gas in order to obtain high sterilization performance. However, since hydrogen peroxide has a strong oxidizing power, it has high corrosivity. For this reason, when the concentration of the hydrogen peroxide gas is increased in order to obtain high sterilization performance, there is a possibility that the device arranged in the sealed space may be corroded and the sterilization efficiency is poor. In addition, high sterilization performance can be obtained by using a method of sterilization under conditions of high humidity or a method of directly spraying hydrogen peroxide water, but it can also be used because it is highly corrosive. There are also problems that are difficult to manage and difficult to manage.

  Then, an object of this invention is to provide the sterilization apparatus and sterilization method which are easy to manage.

  In order to solve the problems and achieve the object, the sterilization apparatus and sterilization method of the present invention are configured as follows.

  As one aspect of the present invention, the sterilizer can detect a gas supply device that supplies hydrogen peroxide gas to the sealed space, the concentration of the hydrogen peroxide gas in the sealed space, and the humidity in the sealed space. Detector, storage means for storing a threshold value for obtaining a predetermined sterilizing effect in the sealed space, and a first integrated value based on an elapsed time of a change in the concentration of the hydrogen peroxide gas supplied in the sealed space And calculating a product of a second integral value according to an elapsed time of a change in humidity in the enclosed space, comparing the calculated product of the first integral value and the second integral value with the threshold value, Control means for determining that the inside of the sealed space has the predetermined sterilizing effect when the product of the first integral value and the second integral value is greater than or equal to the threshold value.

  As one aspect of the present invention, the sterilization method supplies hydrogen peroxide gas to a sealed space, detects the concentration of the hydrogen peroxide gas supplied to the sealed space, and the humidity in the sealed space, Calculating a product of a first integral value according to an elapsed time of a change in concentration of the hydrogen peroxide gas supplied into the sealed space, and a second integral value according to an elapsed time of a change in humidity within the sealed space; The calculated product of the first integral value and the second integral value is compared with the threshold value, and when the product of the first integral value and the second integral value is equal to or greater than the threshold value, the inside of the sealed space has a predetermined sterilization. Judged to have an effect.

  According to the present invention, it is possible to provide a sterilization apparatus and a sterilization method that are easy to manage.

Explanatory drawing which shows typically the structure of the sterilizer which concerns on one embodiment of this invention. Explanatory drawing which shows an example of the relationship between the density | concentration and humidity for calculating the DHv value used for the sterilization method using the same sterilizer, and time. Explanatory drawing which shows an example of the relationship between the DHv value used for the same sterilization method, and the sterilization effect D. FIG. The flowchart which shows an example of the same sterilization method. Explanatory drawing which shows an example of the effect of sterilization of the sealed space using the sterilization method.

  Hereinafter, the structure of the sterilization apparatus 1 and the sterilization method according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5.

  FIG. 1 is an explanatory view schematically showing a configuration of a sterilization apparatus 1 according to an embodiment of the present invention, and FIG. 2 is a concentration and humidity for calculating a DHv value used in a sterilization method using the sterilization apparatus 1. FIG. 3 is an explanatory diagram showing an example of the relationship between time, FIG. 3 is an explanatory diagram showing an example of the relationship between the DHv value used in the sterilization method and the sterilization effect D, and an example of a threshold value for obtaining a predetermined sterilization effect D. FIG. 5 is an explanatory diagram showing an example of the effect of sterilization of the sealed space using the sterilization method.

  As shown in FIG. 1, the sterilizer 1 is connected to a sealed space 100 such as a sealed room. The sterilization apparatus 1 is formed so that a sterilization target such as a sealed space 100 or a device or container disposed in the sealed space 100 can be sterilized with hydrogen peroxide gas (VHP: Vapor Hydrogen Peroxide).

  Note that the sealed space 100 is preferably a space in which the room is sealed. However, even if hydrogen peroxide gas in the sealed space 100 leaks to the outside, the concentration of the hydrogen peroxide gas is small and the airtightness is small. The room is also included. The sterilizer 1 is used for sterilization when the concentration of hydrogen peroxide gas in the sealed space 100 is in a low concentration range. Here, the low concentration zone is, for example, a range in which the concentration of hydrogen peroxide gas in the sealed space 100 is 20 ppm to 150 ppm.

The sterilization in this embodiment is sterilization, and adopts a sterility assurance level (SAL). Further, the sterilization in the present embodiment indicates a level satisfying the sterility assurance level SAL ≦ 10 ⁻⁶ . In addition, the said level is demonstrated below as the sterilization effect D and the display> 6D. Here, “6” of 6D indicates the number of logs (logarithm), and as the bactericidal effect D, for example, SAL ≦ 10 ⁻⁵ is 5D, and SAL ≦ 10 ⁻⁴ is 4D. Similarly, the number of SAL values will be described below using the bactericidal effect D.

  The sterilizer 1 includes a generator 11 that generates hydrogen peroxide gas, a gas supply device 12 that supplies the hydrogen peroxide gas to the sealed space 100, a detector 13 that is disposed in the sealed space 100, and the generator 11. And a control means 14 connected to the gas supply device 12 and the detector 13 via a signal line S and the like.

  The generating device 11 includes an outer member 21, a tank 22, a supply unit 23, and a plate heater 24. The outer member 21 communicates with the sealed space 100 via a pipe 31 described later of the gas supply device 12. The generator 11 is configured to be able to generate hydrogen peroxide gas so that the concentration of the hydrogen peroxide gas in the sealed space 100 is in a low concentration zone.

  The tank 22 is formed so as to be able to store hydrogen peroxide water. In the present embodiment, hydrogen peroxide solution having a concentration of 35 w / w% is used as the hydrogen peroxide solution.

  The supply means 23 is configured to be able to supply a predetermined amount of the hydrogen peroxide solution in the tank 22 onto the plate heater 24. For example, the supply means 23 is a spray capable of spraying hydrogen peroxide solution in a mist form or a nozzle for dropping hydrogen peroxide solution. The plate heater 24 is formed to be capable of generating hydrogen peroxide gas by being heated to 150 ° C. or more and evaporating the supplied hydrogen peroxide solution.

  The gas supply device 12 connects the outer member 21 and the sealed space 100 so that the generated hydrogen peroxide gas can be supplied, and the hydrogen peroxide gas generated in the outer member 21 via the pipe 31 in the sealed space. And a pressure feeding means 32 such as a blower to be supplied to 100. Further, the gas supply device 12 may have an open / close valve for opening and closing the pipe 31. The pressure feeding means 32 is connected to the control means 14 via the signal line S. The pressure feeding means 32 is disposed in the outer member 21, for example.

  The detector 13 is formed so as to be able to detect the concentration of hydrogen peroxide gas in the sealed space 100 and the humidity in the sealed space 100. The detector 13 is configured to be able to transmit the detected concentration and humidity information to the control means 14. A plurality of detectors 13 may be provided. In the present embodiment, humidity indicates relative humidity.

  The control means 14 is formed so as to be able to control the generator 11 and the gas supply device 12. The control means 14 is configured to be able to control the supply and stop of the hydrogen peroxide solution of the supply means 23. The control means 14 is configured to be able to control the operation and stop of the pressure feeding means 32.

  In addition, the control unit 14 includes a storage unit 41. The storage unit 41 stores a DHv0 value that is a threshold value that satisfies a predetermined sterilization effect D (> 6D) in the sealed space 100.

  Further, the control means 14 has the following functions (1) to (4).

  (1) A function of generating hydrogen peroxide gas and supplying it to the sealed space 100.

  (2) A function of calculating a DHv value indicating the state of the sterilization effect D of the sealed space 100 from the detected concentration and humidity.

  (3) A function for comparing the calculated DHv value with the DHv0 value stored in the storage means 41.

  (4) A function of stopping the supply of hydrogen peroxide gas when the DHv value is larger than the DHv0 value.

Next, these functions (1) to (4) will be described.
In function (1), the control means 14 controls the supply means 23, the hydrogen peroxide gas is generated by the generator 11, and the hydrogen peroxide gas generated by driving the pressure feeding means 32 is supplied via the pipe 31. This is a function of supplying the sealed space 100 from the generator 11.

In function (2), the control means 14 receives information on the concentration and humidity detected by the detector 13, and calculates a DHv value based on the information on the concentration and humidity. The DHv value is obtained by the following formula (1).

  Specifically, the DHv value is a first integrated value obtained by integrating a function f (x) obtained from a change in concentration in the enclosed space 100 shown in FIG. It is obtained by integrating the second integrated value obtained by integrating the function f ′ (X) obtained from the change in humidity with time x. This DHv value is a value for estimating the bactericidal effect D by comparing it with a DHv0 value that is a threshold value serving as a reference for the bactericidal effect D.

  In function (3), the control means 14 compares the DHv value calculated in function (2) with the DHv0 value in which the bactericidal effect D stored in the storage means 41 satisfies> 6D.

  In the function (4), when the DHv value is larger than the DHv0 value (DHv> DHv0) as a result of the comparison in the function (3), it is determined that the predetermined sterilization of the sealed space 100 is finished, and the generator 11 It is a function to stop.

Next, the DHv0 value stored in the storage unit 41 and serving as a reference for sterilization termination will be described with reference to FIG.
The DHv0 value is obtained by sterilizing the sealed space 100 a plurality of times under a predetermined condition to obtain a DHv value from the above formula (1), and among these obtained DHv values, the sterilization effect D is> 6D. Is set as a threshold value.

Specifically, first, a plurality of biological indicators (hereinafter referred to as “BI”) are arranged in the sealed space 100. In the present embodiment, BI of Geobacillus stearothermophilus ATCC1298 (10 ⁶ cfu / disc) manufactured by Apex Laboratory, Inc. was used as one of the resistance indicators for hydrogen peroxide gas.

  The sealed space 100 is a space having a different volume or shape. As shown in FIG. 3, different spaces A and B are used as the sealed space 100 in this embodiment.

  Next, the concentration of the hydrogen peroxide gas, the humidity in the sealed space 100, and the sterilization time are set to a plurality of different conditions to sterilize the sealed space 100 respectively. At a predetermined elapsed time from the start of sterilization, evaluation is performed by measuring the number of surviving bacteria of BI in the sealed space 100 to evaluate whether or not the sterilization effect D is> 6D.

  Next, as shown in FIG. 3, the relationship between the sterilization effect D and the DHv value under a plurality of sterilization conditions is obtained. As shown in FIG. 3, from the relationship between the sterilization effect D and the DHv value, the lower limit value of the DHv value that can sterilize the sealed space 100 with the sterilization effect D of> 6D is obtained almost certainly. The lower limit of this DHv value is defined as a DHv0 value that is a threshold value at which the sterilization effect D is> 6D.

  FIG. 3 shows the relationship between the sterilization effect D and the DHv value obtained by performing the above-described sterilization a plurality of times. The solid line in FIG. 3 shows the average value (ave.) Of the sterilization effect D, and the broken line shows Standard deviations (+ σ, −σ) are shown.

  In the present embodiment, as shown in FIG. 3, as a threshold that can surely sterilize the sealed space 100 with a sterilization effect D of 6D, a DHv value that satisfies both the average value and the standard deviation of the sterilization effect D is 6D. (DHv0 value), and this DHv0 value was determined to be 55,000 or more as shown in FIG.

Next, the sterilization method using the sterilization apparatus 1 configured as described above will be described below with reference to the flowchart shown in FIG.
First, the generator 11 is connected to the sealed space 100 via the pipe 31. Next, the control device 14 drives the generator 11 to generate hydrogen peroxide gas, and the gas supply device 12 supplies the hydrogen peroxide gas into the sealed space 100 (step ST1). Thereby, sterilization in the sealed space 100 is started. Next, the concentration of hydrogen peroxide gas in the sealed space 100 and the humidity in the sealed space 100 are continuously detected by the detector 13 from the start of sterilization (step ST2), and transmitted to the control means 14. Note that the concentration and humidity may be detected by the detector 13 every predetermined time.

  When receiving the information on the concentration and humidity detected by the detector 13, the control means 14 calculates a DHv value from the information and the sterilization time using Equation (1) (step ST3).

  Next, the control means 14 compares the calculated DHv value with the DHv0 value (step ST4). When the DHv value is smaller than the DHv0 value (DHv <DHv0) (NO in step ST4), the supply of hydrogen peroxide gas is continued in the sealed space 100 (step ST1).

  When the DHv value is larger than the DHv0 value (DHv> DHv0) (YES in step ST4), the control unit 14 determines that the sterilization effect D in the sealed space 100 satisfies> 6D, and sterilization is finished. To do. Thereby, the control means 14 stops the supply means 23 and the gas supply apparatus 12, and stops supply of hydrogen peroxide gas (step ST5). By these steps, the sterilization apparatus 1 is used to sterilize the sealed space 100 where the sterilization effect D satisfies> 6D.

  Next, examples of sterilization using the sterilization apparatus 1 and the sterilization method will be described below. In this example, the sealed space 100 is sterilized using the above-described sterilization method under the conditions of the following Examples 1 to 12, and the sterilization effects D and DHv under the conditions of Examples 1 to 12 are used. Find the value.

  In this example, the DHv value and the bactericidal effect D are evaluated by comparison with the DHv value and the DHv0 value. In order to evaluate the relationship between the DHv value when the sterilization effect D is> 6D and the above-described DHv0 value, the DHv0 value is set to DHv0 = 55,000, which is the lower limit value. Further, the corrosivity in Examples 1 to 12 is also evaluated.

Example 1
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 6 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 20%. In addition, in this embodiment, humidity shows relative humidity.

(Example 2)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 6 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 30%.

(Example 3)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 6 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 40%.

Example 4
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 6 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 50%.

(Example 5)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 6 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 60%.

(Example 6)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 6 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 70%.

(Example 7)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 12 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 20%.

(Example 8)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 12 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 30%.

Example 9
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 12 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 40%.

(Example 10)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 12 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 50%.

(Example 11)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 12 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 60%.

(Example 12)
The supply means 23 supplies hydrogen peroxide water (35 wt%) to the plate heater 24 at a rate of 12 g / min to generate hydrogen peroxide gas. The humidity in the sealed space 100 at the start of sterilization is 70%.

  The detailed conditions and evaluation method of the sterilization method using Examples 1 to 12 will be described below.

The sealed space 100 is a 450 m ³ space, the hydrogen peroxide gas concentration in the sealed space 100 is set to a low concentration zone, and a plurality of BIs and metal pieces for confirming corrosion are arranged in the sealed space 100.

  The culture container is collected from the sealed space at the elapse of 2 hours, 4 hours, and 6 hours from the start of sterilization, the number of living bacteria is measured, and the sterilization effect D is evaluated.

  The metal piece uses an iron material such as plain steel. The metal pieces are collected from the sealed space when 2 hours, 4 hours, and 6 hours have passed since the start of sterilization, and after standing for 24 hours outside the gas exposure environment, in this embodiment in the indoor environment, the presence or absence of corrosion is evaluated visually. .

  Further, the control unit 14 calculates the DHv values of the first to twelfth embodiments.

Next, the results of Examples 1 to 12 under these conditions are shown. In addition, the result of Example 1 thru | or Example 12 is shown in FIG.
Example 1
In 2 hours from the start of sterilization, the sterilization effect D was 0.6 D, the DHv value was 4,312 and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  In 4 hours from the start of sterilization, the sterilization effect D was 1.8D, the DHv value was 23,496, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  In 6 hours from the start of sterilization, the sterilization effect D = 3.5D, DHv = 64,304, and no corrosion was observed on the metal pieces.

  Although the required bactericidal effect (D> 6D) was not satisfied, DHv> 55,000.

(Example 2)
In 2 hours from the start of sterilization, the sterilization effect D was 1.0 D, the DHv value was 7,437, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  In 4 hours from the start of sterilization, the sterilization effect D was 4.1D, the DHv value was 49,011, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 77,858, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

(Example 3)
In 2 hours from the start of sterilization, the sterilization effect D was 2.7D, the DHv value was 49,243, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  In 4 hours from the start of sterilization, the sterilization effect D was 5.5D, the DHv value was 49,243, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv values were 91, 222, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

Example 4
In 2 hours from the start of sterilization, the sterilization effect D was 4.4D, the DHv value was 10,291, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  At 4 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 56,569, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 81,791, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

(Example 5)
In 2 hours from the start of sterilization, the sterilization effect D was 5.2D, the DHv value was 9,599, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  At 4 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 69,796, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 97,652. In addition, some dullness was seen in the metal piece.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

(Example 6)
At 2 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 12,182, and no corrosion was observed on the metal pieces.

  Although satisfying the required bactericidal effect (D> 6D), DHv <55,000.

  At 4 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 57,105. Some dullness was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 110,586. Some dullness was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

(Example 7)
In 2 hours from the start of sterilization, the sterilization effect D was 3.4D, the DHv value was 9,881, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  In 4 hours from the start of sterilization, the sterilization effect D was 5.6D, the DHv value was 43,504, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 83,297, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

(Example 8)
In 2 hours from the start of sterilization, the sterilization effect D was 4.8D, the DHv value was 14,273, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was not satisfied and DHv <55,000.

  At 4 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 57,545, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv values were 101,218, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

Example 9
At 2 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 19,656, and no corrosion was observed on the metal pieces.

  Although satisfying the required bactericidal effect (D> 6D), DHv <55,000.

  At 4 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 77,547, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 156,463. Some dullness was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

(Example 10)
At 2 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 23,056, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 4 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 97,000. Some dullness was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 188,000. Some dullness was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

(Example 11)
At 2 hours from the start of sterilization, the sterilization effect D was> 6D, the DHv value was 42,083, and no corrosion was observed on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 4 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 135,902. Some dullness was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv values were 254,288. Clear rust was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

(Example 12)
At 2 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 59,204. Some dullness was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 4 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv values were 164,442. Some dullness was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  At 6 hours from the start of sterilization, the sterilization effect D was> 6D and the DHv value was 266,266. Clear rust was seen on the metal pieces.

  The required bactericidal effect (D> 6D) was satisfied, and DHv> 55,000 was satisfied.

  In Example 1, although sterilization was performed for 6 hours and the DHv value was larger than the DHv0 value (DHv = 64,304), the sterilization effect D did not satisfy> 6D. In Example 7, when sterilized for 6 hours and obtained a DHv value larger than the DHv0 value (DHv = 83,297), the sterilization effect D satisfied> 6D.

  According to these examples, under the environment where the humidity in the sealed space 100 at the start of sterilization is 20% as in the case of Example 1 and Example 7, the hydrogen peroxide gas A predetermined sterilization effect D can be obtained by increasing the concentration and ensuring a long sterilization time. However, the predetermined sterilization effect D may not be obtained under the condition where the concentration of hydrogen peroxide gas is low.

  For example, in Example 1 and Example 7, it is possible to obtain a predetermined sterilization effect D by increasing the supply amount of hydrogen peroxide water or the sterilization time. However, in the sealed space 100 at the start of sterilization, The humidity is desired to be higher than 20%.

  Like Example 2 and Example 8, in the environment where the humidity in the sealed space 100 at the start of sterilization is 30%, the sterilization effect D can ensure> 6D under the condition of DHv> DHv0. It was.

  As in Example 3 and Example 9, in an environment where the humidity in the sealed space 100 at the start of sterilization is 40%, the sterilization effect D can ensure> 6D under the condition of DHv> DHv0. It was. When sterilization was performed for 6 hours in Example 9, a slight dullness was confirmed on the metal piece, but also when sterilization was performed for 4 hours, the sterilization effect D was 6D and DHv> DHv0 is satisfied. For this reason, the sterilization method of this embodiment sets the DHv0 value to 55,000, and the control unit 14 stops the generator 11 after determining DHv> DHv0, thereby preventing corrosion.

  Like Example 4 and Example 10, in the environment where the humidity in the sealed space 100 at the start of sterilization is 50%, the sterilization effect D can ensure> 6D under the condition of DHv> DHv0. It was. In Example 10, when sterilization was performed for 4 hours and 6 hours, a slight dullness was confirmed on the metal piece, but when sterilization was performed for 4 hours, DHv = 97,000. For this reason, the sterilization method of this embodiment sets the DHv0 value to 55,000, and the control unit 14 stops the generator 11 after determining DHv> DHv0, thereby preventing corrosion.

  Like Example 5 and Example 11, in the environment where the humidity in the sealed space 100 at the start of sterilization is 60%, the sterilization effect D can ensure> 6D under the condition of DHv> DHv0. It was. In addition, when the sterilization was performed for 6 hours in Example 5 and for 4 hours and 6 hours in Example 11, a slight dullness was confirmed in the metal pieces. However, when sterilization was performed for 4 hours in Example 5, no corrosion was observed. In Example 11, when sterilized for 2 hours, DHv = 42,083, and when sterilized for 4 hours, DHv = 135,902. For this reason, by the sterilization method of this embodiment, the DHv0 value is set to 55,000, and the control unit 14 stops the generator 11 after determining that DHv> DHv0, thereby preventing corrosion.

  As in Example 6 and Example 12, in an environment where the humidity in the sealed space 100 at the start of sterilization is 70%, the sterilization effect D can ensure> 6D under the condition of DHv> DHv0. It was. In addition, when sterilization was performed for 4 hours in Example 6 and for 2 hours and 4 hours in Example 12, some dullness could be confirmed in the metal pieces. Moreover, when sterilization was performed for 6 hours in Example 12, the metal piece was clearly corroded. In an environment where the humidity in the sealed space 100 at the start of sterilization is 70%, if DHv> DHv0, a sterilization effect D of> 6D can be obtained, but there is a high risk of corrosion of metal pieces. For this reason, in an environment where it is necessary to prevent corrosion of metal or the like, it is desirable that the humidity in the sealed space 100 at the start of sterilization is lower than 70%. Further, it can be considered that corrosion occurs more at a humidity of 70% or more.

  As described above, in the sterilization method using the sterilization apparatus 1 according to the present embodiment, as described in the results of Examples 1 to 12, the range is DHv> DHv0 and sterilization is started. The humidity of the sealed space 100 at the time is preferably higher than 20% and not higher than 70%. Furthermore, in order to prevent corrosion of the metal, the humidity is preferably in the range of 30% to 60% when the DHv0 value is 55,000 as described above, for example. Further, in order to prevent corrosion reliably, the humidity in the sealed space 100 at the start of sterilization should be in the range of 30% to 50%, and the humidity should be 30% to 50%. For example, even if the DHv0 value is set higher than 55,000, the sterilization effect D can reliably satisfy> 6D, and corrosion can be prevented.

  According to the sterilization apparatus 1 configured as described above, the sterilization effect D is such that the relative humidity of the sealed space 100 is 30% or more and the DHv0 value is 55,000 or more. It is possible to satisfy> 6D without increasing the density more than necessary.

  Further, as a sterilization method using the sterilization apparatus 1, based on the concentration of hydrogen peroxide gas in the indoor space 100, the humidity in the sealed space 100, and the sterilization time, which are the sterilization conditions of the sealed space 100, When the obtained DHv value is larger than the threshold DHv0 value, the generator 11 is stopped. Thus, the sterilization method can easily obtain the sterilization effect D by managing based on the DHv value and the DHv0 value based on the conditions for sterilization.

  As described above, according to the sterilization apparatus 1 and the sterilization method according to an embodiment of the present invention, the generator 11 is stopped based on the relationship between the preset DHv0 value and the DHv value obtained from the sterilization conditions. Thus, the sterilizing effect can be easily managed.

  The present invention is not limited to the above embodiment. In the above-described example, in the sterilization method using the sterilizer 1, the DHv0 value stored in the storage unit 41 is 55,000, and this DHv0 value is compared with the DHv value obtained under the sterilization conditions. Although the structure which determines the continuation and stop of sterilization was demonstrated, it is not limited to this. For example, the DHv0 value may be a value greater than 55,000. For example, if it exceeds 55,000, it can be set appropriately. However, considering corrosivity, it is desirable that the threshold value at which the humidity at the start of sterilization is 30% to 50% is DHv0 = 55,000.

  In the example described above, the sterilization effect D is 55,000 or more as the DHv0 value satisfying> 6D, but the present invention is not limited to this. For example, when the sterilization effect D is 5D, a DHv0 value that satisfies 5D is obtained, and when the DHv value exceeds the obtained DHv0 value, it may be determined that sterilization is completed. Similarly, the standard of the sterilization effect may be a standard other than the sterility assurance level (SAL). That is, if the sealed space 100 is sterilized using hydrogen peroxide gas, as in this embodiment, the concentration of the hydrogen peroxide gas and the humidity of the sealed space are managed, the threshold value is obtained, and the threshold value is actually The DHv value at the time of sterilization is compared, and if the DHv value exceeds the threshold value, it may be estimated that the sterilization is completed.

  Further, in the above-described example, the configuration has been described in which the generator 11 generates the hydrogen peroxide gas by evaporating the hydrogen peroxide solution supplied by the supply unit 23 by the plate heater 24. However, the generator 11 can generate the hydrogen peroxide gas. If it is, it will not be limited to these structures.

  Moreover, although the gas supply apparatus 12 demonstrated the structure which arrange | positions the pumping means 32 in the outer shell member 21 of the generator 11 in the example mentioned above, it is not limited to this. For example, the structure arrange | positioned in the piping 31 may be sufficient, and the structure provided with two or more may be sufficient. Further, the gas supply device 12 may be configured to have a device for efficiently circulating the hydrogen peroxide gas in the sealed space 100 or a device for uniformly distributing the hydrogen peroxide gas. In addition, various modifications can be made without departing from the scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Sterilizer, 11 ... Generator, 12 ... Gas supply device, 13 ... Detector, 14 ... Control means, 21 ... Outer member, 22 ... Tank, 23 ... Supply means, 24 ... Plate heater, 31 ... Piping, 32 ... pressure feeding means, 41 ... storage means, 100 ... sealed space, S ... signal line.

Claims (10)

A gas supply device for supplying hydrogen peroxide gas to the sealed space;
A detector capable of detecting the concentration of the hydrogen peroxide gas in the sealed space and the humidity in the sealed space;
Storage means for storing a threshold value for obtaining a predetermined sterilizing effect in the sealed space;
Calculating a product of a first integral value according to an elapsed time of a change in concentration of the hydrogen peroxide gas supplied into the sealed space, and a second integral value according to an elapsed time of a change in humidity within the sealed space; The calculated product of the first integral value and the second integral value is compared with the threshold value, and when the product of the first integral value and the second integral value is equal to or greater than the threshold value, the inside of the enclosed space is the A control means for determining that it has a predetermined sterilizing effect;
A sterilizing apparatus comprising:   The sterilizer according to claim 1, wherein the humidity at the start of the supply of the hydrogen peroxide gas in the sealed space is 30% or more and 70% or less in terms of relative humidity.   The threshold value is a product of the first integral value and the second integral value that provides a predetermined sterilizing effect of the sealed space, and is the product of the calculated first integral value and the second integral value. The sterilizing apparatus according to claim 1, wherein the sterilizing apparatus is provided.   2. The sterilizing apparatus according to claim 1, wherein the control unit stops the supply device after determining that the inside of the sealed space has the predetermined sterilizing effect.   The sterilizer according to any one of claims 1 to 4, wherein the concentration of the hydrogen peroxide gas in the sealed space is in a low concentration zone. Supply hydrogen peroxide gas to the sealed space,
Detecting the concentration of the hydrogen peroxide gas supplied to the sealed space and the humidity in the sealed space;
Calculating a product of a first integral value according to an elapsed time of a change in concentration of the hydrogen peroxide gas supplied into the sealed space, and a second integral value according to an elapsed time of a change in humidity within the sealed space;
Comparing the calculated product of the first integral value and the second integral value with the threshold;
The sterilization method, wherein when the product of the first integral value and the second integral value is greater than or equal to a threshold value, it is determined that the sealed space has a predetermined sterilization effect.   The sterilization method according to claim 6, wherein the humidity at the start of the supply of the hydrogen peroxide gas in the sealed space is 30% or more and 70% or less in terms of relative humidity.   The threshold value is a product of the first integral value and the second integral value that provides a predetermined sterilizing effect of the sealed space, and is the product of the calculated first integral value and the second integral value. The sterilization method according to claim 6, wherein the sterilization method is provided.   The sterilization method according to claim 6, wherein the supply device is stopped after determining that the sealed space has the predetermined sterilization effect.   The sterilization method according to any one of claims 6 to 9, wherein the concentration of the hydrogen peroxide gas in the sealed space is in a low concentration zone.

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