SU1681860A1 - Method for surface decontamination - Google Patents

Abstract

The invention relates to the disinfection of the surfaces of the process equipment and can be used in the microbiological, medical and food industries. The purpose of the invention is the inactivation of spore forms of microorganisms and the acceleration of decontamination. The method involves treating equipment surfaces with hydrogen peroxide vapors, and peroxohydrate ammonium fluoride is used as a source of hydrogen peroxide vapor when heated to, and decontamination of surfaces is carried out at a pressure of the resulting gaseous medium from 0.8 to 1 atm for 120 minutes. 6 tab.

Description

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The invention relates to the disinfection of the surfaces of the process equipment and can be used in the microbiological, medical and food industries.

The purpose of the invention is the inactivation of spore forms of microorganisms and the acceleration of decontamination. .

The method involves treating equipment surfaces with hydrogen peroxide vapor, and ammonium fluoride peroxohydrate is used as a source of hydrogen peroxide vapor when heated to 70-86 ° C. and the decontamination of surfaces is carried out at a pressure of the resulting gaseous medium from 0.8 to 1 atm for 120 minutes.

Ammonium fluoride peroxohydrate (MSRP HzO2) is a white crystalline substance containing 47.89% hydrogen peroxide and 22.53% active oxygen. The substance has the ability to release hydrogen peroxide into the gas phase. At 40 ° C for 2 hours, 30% H202 is released into the gas phase, the remaining hydrogen peroxide is retained associated with the solid. At 60 ° С in 2 hours up to 90% of Н202 is transferred to the gas phase. contained in ammonium fluoride peroxohydrate.

The processing in this method is subjected to the surfaces of the devices and equipment, which are used under conditions of microbial contamination, the processing of which by the disinfectant in the form of an aerosol is difficult,

As a test object, a stable form of microorganisms — a suspension of anthracoid spores (strain 250) is used with a concentration of suspension n 107sp / ml.

Example. The test surfaces, contaminated with B. anthracoldes spores in multiple repetition of the samples, are placed in sealed chambers into which the vapor – gas phase containing peroxide BOO 00 is fed.

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The hydrogen produced by thermal conversion of ammonium fluoride peroxyhydrate in a reactor connected by chambers with a system of hoses. A pump mounted at the entrance to the reactor is used to circulate the vapor phase decontaminant in the system.

The incubation time of the treated test objects is 1-7 days at 28-37 ° C.

The results of processing the test surfaces contaminated with anthracoid spores (suspension concentration of 10 5 lb / ml) are presented in Table. 1-3.

When the decomposition temperature of the solid carrier is 60 ± 5 ° C, the complete transfer of hydrogen peroxide from the solid carrier to the vapor – gas phase does not occur; therefore, the complete decontamination of the test surfaces is not achieved.

When the decomposition temperature of the solid carrier is 95 ± 5 ° C, individual growth of microorganisms is observed on individual test surfaces, since with increasing decomposition temperature of the solid carrier above 86 ° C, the content of hydrogen peroxide in the vapor-gas phase decreases.

Table 4 presents the results of the decontamination of surfaces contaminated with the spore form B.anthracoides of piece 250, which are comparative with the known method.

From Table 4 it follows that if the exposure time of the contaminated test surfaces in the chambers with the vapor-gas phase of hydrogen peroxide obtained in accordance with the method is less than 2 hours, the growth of microorganisms is observed on separate test surfaces. When exposed to 2 hours, all test surfaces are completely decontaminated. A holding time of more than 2 hours is impractical, since with an exposure of 2 hours a reliable decontaminating effect is achieved.

A comparison of the effect of the vapor-gas phase obtained by heating a solid carrier of hydrogen peroxide and by heating hydrogen peroxide solutions shows that during exposure (from 60 to 150 minutes by a known method), it is not possible to decontaminate the test surfaces, and in the proposed method, the complete decontamination is achieved with a 120-minute surface finish.

When the temperature in the reactor is 60 ± 5 ° С with the same amount of solid carrier of hydrogen peroxide is minimal

The excess pressure in the system does not exceed 0.8 atm. When decomposing the same amount of solid support at a temperature of 78 ± 8 ° C, the excess pressure is 1 atm. The decrease in overpressure in the system to a value less than 0.8 atm leads to a sharp decrease in the degree of decontamination of surfaces as compared with that

observed at an overpressure of 0.8 - 1 these, an increase in pressure above 1 atm requires measures to strengthen the sealing system,

Reactor temperature rise

above these limits, promotes rapid decomposition of the solid carrier of hydrogen peroxide in the reactor, a sharp increase in overpressure to 2 of these, and the need to release it through the drain valve to avoid a leak. This leads to a loss of decontamination from the system and, consequently, to a decrease in the efficiency of decontamination.

Ammonium fluoride peroxohydrate has a higher kinetic constant for the inactivation of spores of B. anthracoides (a test object of a stable form of microorganisms) compared to peroxide

hydrogen, which additionally increases the reliability of the decontamination of surfaces seeded with both vegetative and spore forms of microorganisms (see tab, 5). Studies on the corrosion activity of ammonium fluoride peroxohydrate show the resistance of representatives of the main groups of technical materials to its effects (see table 6).

Solid carrier of hydrogen peroxide

makes it convenient to store, transport and use it for decontamination of hard-to-reach surfaces of instruments and equipment with hydrogen peroxide.

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Claims (1)

Invention Formula A method of decontaminating surfaces, including their treatment with hydrogen peroxide vapor, characterized in that. what with In order to inactivate spore forms of microorganisms and accelerate decontamination, ammonium fluoride peroxohydrate is used as a source of hydrogen peroxide vapor when heated to 70-8b ° C, and the surface is decontaminated at a pressure of 0.8 to 1 atm. Processing the test surfaces at the decomposition temperature of the solid peroxide carrier hydrogen 78 ± 8 ° C. temporary processing 2 h Note. (+) - the growth of microorganisms (-) - no growth of microorganisms. Processing the test surfaces at the decomposition temperature of the solid peroxide carrier hydrogen 60 ± 5 ° C, processing time 2 h Table 3 Processing the test surfaces at the decomposition temperature of the solid peroxide carrier hydrogen 95 ± 5 ° C processing time 2 h Surface Decontamination Results Table 1 Table 2 Table 4 Table 5 Constants of the kinetics of inactivation of spores of B. Anthracoldes, pieces 250, p 107 C / ml Table 6 Corrosion resistance of surfaces of various materials to the action of ammonium fluoride peroxohydrate solution (immersion method)