Tso3 Inc.

Ts03 Inc.

Sylvie Dufresne

Helene Leblond

Cynthia Martel

Karine Martel

Nancy Dassie

Bruno Tremblay

Jean-Martin Vallieres

Jonathan Laflamme

Simon Robitaille

David Sohier

Francis Therrien

Claudia Bedard

Cécile Chevalier

Richard Turcot

Hélène Leblond

Marie-Christine Gagne

Cecile Chevalier

Disclosed is a method of sterilizing an article by sequentially exposing the article under vacuum first to a gaseous conditioning agent for forming radicals and then to a sterilant. The preferred conditioning agent is hydrogen peroxide and the preferred sterilant is ozone. The chamber is initially evacuated to a first vacuum pressure and then sealed for the remainder of the sterilization process and during all sterilant injection cycles, without removal of any component of the sterilization atmosphere, which means without any measures to reduce the water vapor content. Keeping the chamber sealed and maintaining the conditioning agent and the radicals generated thereby in the chamber for the sterilization with sterilant results in a synergistic increase in the sterilization efficiency and allows for the use of much lower sterilant amounts and sterilization cycle times than would be expected from using the conditioning agent and the sterilant in combination.

Sterilization method and apparatus

A method is provided for establishing resistance characteristics of a biological indicator in a sterilization process using a sterilant vapor. The method includes the step of creating a biological indicator inactivation profile by obtaining differential sterilant vapor pressure values in a sterilization chamber during sterilant vapor injection and determining D-values as a function of the differential sterilant vapor pressure values obtained. The biological indicator inactivation profile, when represented as a function of differential sterilant vapor pressure, may be linear over the full range of inactivation. The biological indicator inactivation profile may be created by injecting the sterilant vapor into the sterilization chamber and measuring biological indicator survival at different differential sterilant vapor pressure values. The method may include providing biological indicator inactivation data during sterilization at a given sterilization chamber temperature and initial sterilant concentration for use in creating the biological indicator inactivation profile at another temperature and sterilant concentration.

Method for establishing resistance characteristics of a biological indicator

An apparatus for sterilizing a load in a sterilization chamber according to specific characteristics of the load without direct measurement of the load conditions. The apparatus preferably admits sterilant gas into the sterilization chamber under vacuum; during admission of the sterilant gas, the apparatus monitors a sterilant condensation related parameter or data in the sterilization chamber. The apparatus detects the occurrence of condensation and determining a value of the condensation related parameter while detecting condensation and, selects a sterilization cycle among a plurality of predetermined sterilization cycles according to the condensation related data. The apparatus then performs the selected sterilization cycle for sterilizing the load. The condensation related data may be the sterilant dew point, a degree of condensation, or an amount of condensation which may be determined in monitoring the chamber pressure during sterilant gas admission. The sterilization process may be controlled dynamically according to the determined condensation related data.

Sterilization apparatus and adaptive control thereof

A method for control of a process for sterilizing a load in a sterilization chamber according to specific characteristics of the load without direct measurement of the load conditions. The method preferably includes admitting sterilant gas into the sterilization chamber under vacuum; during admission of the sterilant gas, monitoring a sterilant condensation related parameter or data in the sterilization chamber; detecting the occurrence of condensation and determining a value of the condensation related parameter while detecting condensation; selecting a sterilization cycle among a plurality of predetermined sterilization cycles according to the condensation related data; and performing the selected sterilization cycle for sterilizing the load. The condensation related data may be the sterilant dew point, a degree of condensation, or an amount of condensation which may be determined in monitoring the chamber pressure during sterilant gas admission. The sterilization process may be controlled dynamically according to the determined condensation related data.

Sterilization methods and apparatus and adaptive control thereof

A method for controlling condensation of hydrogen peroxide at a preselected temperature within a sealed sterilization chamber including an article to be sterilized includes the steps of applying to the sealed chamber a vacuum of a first pressure sufficient to evaporate, at the preselected temperature, an aqueous solution of hydrogen peroxide of a first concentration. The hydrogen peroxide solution is then evaporated into a water vapor component and a hydrogen peroxide vapor component. The evaporated solution is injected into the sealed chamber in repeated pulses. The injecting is terminated once a preselected second pressure, higher than the first pressure, is reached in the chamber. The pulse volume is selected to allow selective control of the condensation of the hydrogen peroxide vapor component to achieve a layer of micro-condensation of hydrogen peroxide on the article, which layer has a second hydrogen peroxide concentration higher than the first hydrogen peroxide concentration.

A method of controlling unwanted condensation of hydrogen peroxide in a sterilization chamber at a preselected temperature is disclosed. The method includes the steps of maintaining the sterilization chamber at a vacuum pressure below the pressure at which hydrogen peroxide will boil at the preselected temperature, evaporating successive pulses of hydrogen peroxide, and injecting the evaporated hydrogen peroxide into the chamber, whereby the volume of each pulse of hydrogen peroxide is less than 75 &#x3bc;L, preferably less than 35 &#x3bc;L, most preferably less than 20 &#x3bc;L. Sterilization results are improved by controlling unwanted condensation of hydrogen peroxide.

Hydrogen peroxide sterilization method

A method of sterilizing an article by sequentially exposing the article to hydrogen peroxide and ozone is disclosed. The article is exposed under vacuum first to an evaporated aqueous solution of hydrogen peroxide and subsequently to an ozone containing gas. The exposure is carried out without reducing the water vapor content of the sterilization atmosphere, the water vapor content being derived from the aqueous solvent of the hydrogen peroxide solution and from the decomposition of the hydrogen peroxide into water and oxygen. The complete sterilization process is carried out while the chamber remains sealed and without removal of any component of the sterilization atmosphere. For this purpose, the chamber is initially evacuated to a first vacuum pressure sufficient to cause evaporation of the aqueous hydrogen peroxide at the temperature of the chamber atmosphere. The chamber is then sealed for the remainder of the sterilization process and during all sterilant injection cycles. Keeping the chamber sealed and maintaining the hydrogen peroxide and its decomposition products in the chamber for the subsequent ozone sterilization step results in a synergistic increase in the sterilization efficiency and allows for the use of much lower sterilant amounts and sterilization cycle times than would be expected from using hydrogen peroxide and ozone in combination.

The present invention provides a method and apparatus for sterilizing articles using an ozone-containing gas, where condensation of water from the sterilization atmosphere during the sterilization process is substantially prevented. The inventive sterilization method includes providing a sterilization chamber and placing an article into the sterilization chamber. The sterilization chamber is sealed prior to equalizing the temperature of the article and the atmosphere in the sterilization chamber. A vacuum is applied to achieve a preselected vacuum pressure in the sterilization chamber. Once the vacuum pressure is set, water vapour is supplied to the sterilization chamber. Ozone-containing gas is then supplied to the sterilization chamber and the sterilization chamber remains sealed for a preselected treatment period, where the sterilization chamber remains sealed throughout the whole process. Finally, vacuum in the sterilization chamber is released.

Method and apparatus for ozone sterilization

The invention relates to an improvement in a method for sterilizing an article in a sterilizing chamber by exposing the article to humidified ozone in at least two consecutive sterilizing cycles, the improvement comprising, after the first of said consecutive sterilizing cycles and before the second of said consecutive sterilizing cycles, removing from the sterilizing chamber any condensed water present.

Growing community of inventors

CA

Sylvie Dufresne