FI82381B - Control indicator for gas sterilization - Google Patents

Description

82381 1 Inspection indicator for gas sterilization Kontrollindikator för gassterilisering 5 The invention relates to an inspection indicator for inspecting gas sterilization with percarboxylic acid vapors, preferably peracetic acid vapors, which indicator is formed, e.g.

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It is an inspection indicator for controlling the handling of objects and instruments, especially heat-sensitive instruments, in a closed chamber or in an autoclave gas sterilization. It is used especially in medical institutions as well as in the far-15 machinery industry.

In addition to the already known and long-used gas sterilization methods using ethylene oxide and formaldehyde, gas sterilization with percarboxylic acid vapor has now been added. Biological control of gas sterilizers

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'7 prepared against bacilli Bacillus subtilus or Bacillus stearot- ·· ·.

'hermophilus spores, which must be carried out at regular intervals, eg semi-annually, in which case a large number of spore strips must be distributed throughout the sterilizer space and germinated for several days in order to establish the functionality of the sterilizer. However, this cannot make any statement as to whether the packaged items to be sterilized have already undergone a sterilization process. Verification indicators for gas sterilization with percarboxylic acid vapors, which also. referred to as processing indicators is not known.

The object of the invention is to provide an indicator for daily sterilization with peracetic acid vapors in a chamber or in an autofilf • clave, which indicates the treatment which has taken place and thus to avoid confusion with the sterile goods which have not yet been treated.

35 · · • · • · 2 82381 ^ Em. In order to achieve this, the invention is mainly characterized in that the dye solutions contain one or more dyes which are bleached so rapidly by oxidizing action that they can be used to demonstrate the sterilization treatment of objects under practical conditions.

It is an object of the invention to provide an indicator for inspecting the treatment of packaged sterile goods with peracetic acid vapors, which indicator shows the treatment carried out by an optically perceptible change, thus avoiding interference with the sterile goods still to be treated, and thus ensures rapid control. Since the rate of the color loss phenomenon varies depending on the oxidation resistance of the selected dye, it was necessary to find a dye whose color can be removed in a short time and which is thus suitable as a high-quality indicator.

According to the invention, this object is thus achieved by exploiting the strong oxidizing and bleaching effect of peracetic acid vapors on certain dyes suitable for it.

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According to the invention, a 0.5% aqueous solution of crystal: violet is preferably used. Further, aqueous solutions of, for example, the following dyes can be used: Victorian blue, Chinese blue, cotton blue, gentian blue, methyl violet, light green, malachite green, ti-25 pine fuchsin, alkaline fuchsin and acid fuchsin.

The indicators are attached to the surface of the sterile package and / or placed inside the package.

.. 30 The control indicator according to the invention is prepared by preparing II an aqueous solution of a certain dye.

: Ko. according to the invention, the dye is one which loses its color due to the oxidizing effect of the sterilant.

T. 35 3 82381 Ί For example, filter paper is immersed in an aqueous dye solution, which is dried and then attached to the surface of the sterile container or inside the package.

5 The object to be sterilized is then taken to a sterilizer, where it is sterilized by steam of peracetic acid at a temperature of about 45 ° C. Sterilization can be indicated by the inspection indicator according to the invention, because the color of the filter paper or the like treated with the dye solution disappears under the influence of peracetic acid vapors.

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Application examples

To prepare the indicator, the filter paper to be stained is immersed for about 5 minutes a.o. dye solution and then dried, e.g., by pendants in air.

Reference P.G. According to Simon, Hygiene + Hadizin 12 (1987) 416, the area of the ceramic indicators must be at least 1 cm2, but not more than 3.5 cm2. They are attached to the surface 20 of the sterile package and / or placed inside the package.

The manufactured colored chemoindicators are very well thief-- resistant to action unless exposed to direct sunlight for long periods of time-! light.

At a temperature of 45 ° C and an initial vacuum of 2.66 kPa (-20 mmHg), the peracetic acid vapors provide complete decolourisation of the filter paper absorbed in a glass desiccator with a 0,5% crystal violet solution in 5 to 10 minutes.

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Claims (3)

1. Control indicator to control a gas sterilization that occurs with percarbon acid Angels, most preferably with peracetic acid vapors, which indicator consists of e.g. a filter paper impregnated with dye solutions of some concentration and then dried, can be characterized in that the dye solutions contain one or more dyes which fade so quickly by oxidative effect that the indicator can be used to prove the sterilization of the articles in practice. 10 conditions. Control indicator according to claim 1, characterized in that the dye which quickly fades by oxidative action is, for example, crystal violet, methyl violet, light green, malachite green, diamond fuxin, basic fuxin or acid fuxin. Control indicator according to claim 1 or 2, characterized in that the dye solution is advantageously a 0.5% by weight crystal violet - aqueous solution. 20 25 30 35