Apparatus And Method For Sterilizing Items

• US 20120230868A1
• Filed: 05/07/2012
• Published: 09/13/2012
• Est. Priority Date: 11/15/2006
• Status: Active Grant

• Current Assignee: Mhi Health Devices LLC
• Original Assignee: Micropyretics Heater International, Inc.
• Inventors: Reddy, Ganta S., Vissa, Ramgopal, Sekhar, Jaingesh A.
• Granted Patent: US 8,945,468 B2
• Time in Patent Office: Days
• US Class Current: 422/26
• CPC Class Codes: A61L 2/07 Steam
• CPC Class Codes: A61L 2/208 Hydrogen peroxide
• CPC Class Codes: A61L 2202/122 Chambers for sterilisation
• CPC Class Codes: A61L 2202/24 Medical instruments, e.g. endoscopes, catheters, sharps
• CPC Class Codes: A61L 2202/26 Textiles, e.g. towels, beds, cloths

Abstract

A sterilizing apparatus includes an enclosure defining an interior chamber and a door for accessing the interior chamber. A fluid source communicates with the chamber to supply a working fluid thereto. A heater heats the fluid in the chamber and a pump moves the fluid in the chamber by the heater. A valve communicates with the chamber and with the exterior of the chamber and is configured to vent the fluid in the chamber to the exterior at a pressure of approximately one atmosphere. Such provides superheating and concentrating of the working fluid in the chamber. A method of sterilization includes introducing a working fluid into an interior chamber and circulating the fluid through at least one recirculation loop having a heater for heating the fluid to an operational temperature suitable for killing microorganisms. The method further provides for killing of very high temperature resistant microorganisms.

Claims

1. A method of sterilizing at least one item, comprising:

introducing a first working fluid into an interior chamber holding the item to be sterilized;

circulating the first working fluid in the interior chamber through at least one fluid tight recirculation loop having a heater in thermal communication therewith for heating the first working fluid up to an operational temperature suitable for killing microorganisms;

venting fluid from the chamber so as to maintain a pressure therein of approximately one atmosphere;

varying the concentration of the first working fluid within the interior chamber; and

exposing the item to be sterilized to the heated first working fluid in the interior chamber in a first mode of sterilization.

2. The method of claim 1, further comprising:

introducing a second working fluid into the interior chamber holding the item to be sterilized;

circulating the second working fluid in the interior chamber through at least one fluid tight recirculation loop having a heater in thermal communication therewith for heating the second working fluid up to an operational temperature suitable for killing microorganisms;

venting fluid from the chamber so as to maintain a pressure therein of approximately one atmosphere varying the concentration of the second working fluid within the interior chamber; and

exposing the item to be sterilized to the heated second working fluid in the interior chamber in a second mode of sterilization.

3. The method of claim 1, wherein the first mode of sterilization includes one of wet heat sterilization, dry heat sterilization, or chemical sterilization, wherein the chemical sterilization includes at least one of a liquid chemical or gaseous chemical.

4. The method of claim 2, wherein the second mode of sterilization includes another of wet heat sterilization, dry heat sterilization, or chemical sterilization, wherein the chemical sterilization includes at least one of a liquid chemical or gaseous chemical.

5. The method of claim 1, further comprising varying the concentration of the first working fluid within the interior chamber to a pre-set value, wherein the interior chamber includes an initial fluid, comprising:

introducing the first working fluid to the interior chamber at a concentration greater than or equal to the pre-set value;

heating the mixture of the first working fluid and initial fluid;

venting a portion of the mixture of the first working fluid and the initial fluid from the interior chamber;

preventing substantially any fluid from the environment from entering the chamber; and

continuing the introducing, heating, venting, and preventing steps until the concentration of the working fluid in the chamber reaches the pre-set value.