Abstract:
The invention relates to a sterilizers and methods of sterilization of an instrument. The sterilizer includes an ozone generator, an air mover, an oxygen concentrator, and a controller. The ozone generator, which is housed by the sterilization chamber, generates at least one plasma field. The air mover circulates air through the sterilization chamber. The oxygen concentrator delivers oxygen-concentrated air to the sterilization chamber. The controller communicates with the ozone generator, the air mover, and the oxygen concentrator. The sterilizer may also include a battery to power the components of the sterilizer. A portable case may house the sterilizer.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This U.S. patent application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application 62/116,769, filed on Feb. 16, 2015, which is hereby incorporated by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    This disclosure relates to methods and apparatuses for sterilizing an object using ozone. 
       BACKGROUND 
       [0003]    Sterilization generally entails the elimination of microbiological organisms to achieve asepsis, a sterile microbial environment. Medical professionals generally need and use sterilized equipment for treating patients, so as to avoid preventable infections or complications that may occur when using non-sterilized equipment. The sterilization of medical equipment can be challenging in non-hospital environments (e.g., in the field) or in third world countries that have limited access to power and clean water. Sterilization can generally be achieved by applying heat, chemicals, irradiation, high pressure, and filtration or combinations thereof. 
         [0004]    In general, surgical instruments that enter an already aseptic part of the body (such as the bloodstream, or penetrating the skin) should be sterilized to a low sterility assurance level, or SAL. Examples of such instruments include scalpels, hypodermic needles, etc. A commonly used method for sterilization is heat sterilization, such as by an autoclave, sometimes called a converter. Autoclaves commonly use steam heated to 121-134° C. (250-273° F.). To ensure proper sterilization, most autoclaves have meters and charts that record or display pertinent information such as temperature and pressure as a function of time. Autoclaves, while effective, can be relatively slow and require routine cleaning. Further, autoclaves should not be overcrowded to allow even penetration of steam and are therefore limited as to the number of instruments that can be sterilized at any given time. 
       SUMMARY 
       [0005]    A sterilizing system may include a sterilization chamber, an ozone generator in pneumatic communication with the sterilization chamber, and a controller in communication with ozone generator. The ozone generator may utilize a cold plasma method to generate ozone for sterilizing an object received in the sterilization chamber. The controller may control operation of the ozone generator. The system may optionally include an oxygen concentrator in pneumatic communication with the sterilization chamber that feeds air rich in diatomic oxygen molecules into the sterilization chamber. The diatomic oxygen rich air aids ozone generation through the cold plasma method. The system may also optionally include an air mover arranged to circulate air through the sterilization chamber. The controller may control the oxygen concentrator and the air mover and coordinate operation of its controlled components to achieve a threshold ozone level within the sterilization chamber. The controller, ozone generator, oxygen concentrator, and air mover may receive power from an external power source or a power source integral within the sterilization system. A portable case may house all of the components of the sterilization system, allowing portability and use of the sterilization system in remote locations. 
         [0006]    One aspect of the disclosure provides a sterilizer that includes a sterilization chamber, an ozone generator, an air mover, an oxygen concentrator, and a controller. The sterilization chamber houses the ozone generator. The ozone generator generates at least one plasma field in the sterilization chamber. The air mover is in fluid communication with the sterilization chamber and circulates air through the sterilization chamber. The oxygen concentrator is in fluid communication with the sterilization chamber and delivers oxygen-concentrated air to the sterilization chamber. The controller is in communication with the ozone generator, the air mover, and the oxygen concentrator. 
         [0007]    Implementations of the disclosure may include one or more of the following optional features. In some implementations, the sterilizer may further include a power source. The power source is in electrical communication with the ozone generator, the air mover, the oxygen concentrator, and the controller. Additionally, the sterilizer may further include a timer used to activate and deactivate at least one of the ozone generator, the air mover, or the oxygen concentrator to maintain a threshold ozone level within the sterilization chamber. In some examples, the controller controls ozone generation to maintain a threshold ozone level of about 4,000 parts per million within the sterilization chamber. This control may be accomplish by pulsing power feed to the ozone generator, maintaining an air recirculation rate of the air mover between about four liters per minute and about six liters per minute, and maintaining an oxygen concentration of the oxygen concentrator of at least seventy-five percent. 
         [0008]    In some implementations, the controller includes a toggle switch that controls activation and deactivation of at least one of the ozone generator, the air mover, or the oxygen concentrator. A utensil tray may be removably housed by the sterilization chamber. In some examples, the sterilizer includes an ozone meter in communication with the controller that measures an ozone concentration in the sterilization chamber. Additionally, the sterilizer may further include one or more of an oxygen meter in communication with the controller that measures an oxygen concentration in the sterilization chamber, an oxygen meter in communication with the controller that measures an oxygen concentration of the oxygen-concentrated air delivered by the oxygen concentrator, and an air flow meter in communication with the controller that measures a flow rate of the air circulated by the air mover. Implementations of the disclosure may further include a display. The display is in communication with the controller. Additionally, the display displays information associated with the operation of the sterilizer. 
         [0009]    In some implementations, the sterilizer includes one or more spray nozzles, a pump, and a fluid reservoir. The one or more spray nozzles are located in the sterilization chamber. The pump is in fluid communication with one or more spray nozzles, and the fluid reservoir is in fluid communication with the pump. In some examples, the fluid reservoir is in fluid communication with the sterilization chamber and the pump circulates a rinse fluid between the fluid reservoir and the sterilization chamber. 
         [0010]    The sterilizer may further include a valve. The valve is in fluid communication with the air mover. Additionally, the valve moves between a closed state and an open state. When the valve is in an open state, the valve directs ozone generated by the ozone generator to the fluid reservoir. In some examples, the valve includes a valve body and a valve seat. The valve body defines a port. The valve seat is located in the valve body. Additionally, the valve seat moves between a closed position seated against the port and an open position spaced from the port when the port receives a connector stud. 
         [0011]    In some implementations, the sterilizer includes a rinsing chamber, one or more spray nozzles, a pump, and a fluid reservoir. The one or more spray nozzles are located in the rinsing chamber. The pump is in fluid communication with one or more spray nozzles. The fluid reservoir is in fluid communication with the pump. In some examples, the fluid reservoir is in fluid communication with the rinsing chamber and the pump circulates a rinse fluid between the fluid reservoir and the rinsing chamber. 
         [0012]    In some implementations, the sterilizer includes an exhaust meter. The exhaust meter is in fluid communication with the sterilizer chamber and in electrical communication with the controller. Additionally, the exhaust meter measures at least one of an exhaust flow of gas out of the sterilization chamber or an ozone concentration of the exhaust flow of gas. The controller triggers an alarm when the ozone concentration of the exhaust flow of gas is greater than a threshold ozone concentration. The sterilizer may further include a case that houses the sterilization chamber, the air mover, the oxygen concentrator, and the controller. 
         [0013]    Another aspect of the disclosure provides a method of sterilizing an instrument. The method includes receiving an instrument in a sterilization chamber and generating at least one plasma field in the sterilization chamber using an ozone generator. The ozone generator is located in the sterilization chamber. The at least one plasma field generates ozone by interacting with Oxygen in the sterilization chamber. The method also includes delivering oxygen-concentrated air to the sterilization chamber and circulating the ozone within the sterilization chamber. 
         [0014]    This aspect may include one or more of the following optional features. In some implementations, the method further includes ceasing sterilization after a threshold period of time by ceasing generation of the at least one plasma field, ceasing delivery of oxygen-concentrated air to the sterilization chamber, and/or ceasing circulation of the ozone within the sterilization chamber. In addition, the method may further include measuring an ozone level within the sterilization chamber and triggering an alarm when the ozone level drops below a threshold ozone level before ceasing sterilization. 
         [0015]    In some examples, the method includes delivering ozone from the sterilization chamber to a water reservoir. Additionally or alternatively, the method may further include spraying a rinse fluid on the received instrument within the sterilization chamber. The method may further include recirculating the rinse fluid between a fluid reservoir and the sterilization chamber. Moreover, the method may include delivering ozone from the sterilization chamber to the fluid reservoir to sterilize the rinse fluid. 
         [0016]    In some examples, the method includes receiving the instrument in a rinsing chamber and spraying a rinse fluid on the received instrument within the rinsing chamber. Additionally, the method may include recirculating the rinse fluid between the fluid reservoir and the rinsing chamber. The method may further include delivering ozone from the sterilization chamber to the fluid reservoir to sterilize the rinse fluid. 
         [0017]    In some implementations, the method includes generating at least 4,000 parts per million of ozone within the sterilization chamber. Additionally or alternatively, the method includes circulating the ozone within the sterilization chamber at a rate of about five liter per minute. The method may further include delivering oxygen-concentrated air to the sterilization chamber at a rate of about 1.5 liter per minute. The air delivered to the sterilization chamber has an oxygen concentration of at least seventy-five percent. In some implementations, the method includes exhausting air from the sterilization chamber at a rate of about 0.5 liters per minute. 
         [0018]    The details of one or more implementations of the disclosure are set forth in the accompanying drawings and the description below. Other aspects, features, and advantages will be apparent from the description and drawings, and from the claims. 
     
    
     
       DESCRIPTION OF DRAWINGS 
         [0019]      FIG. 1  is a schematic view of an example sterilization system. 
           [0020]      FIG. 2  is a perspective view of an example sterilization chamber housing an ozone generator. 
           [0021]      FIG. 3  is a perspective view of an example sterilization system housed within a portable case. 
           [0022]      FIG. 4  is a schematic view of an example sterilization system and communication connections therein. 
           [0023]      FIG. 5  is a schematic view of an example sterilization system having an exhaust system. 
           [0024]      FIGS. 6-9  are schematic views of example user interfaces. 
           [0025]      FIG. 10  is a schematic view of an example user interface having a single on/off switch. 
           [0026]      FIG. 11  is a schematic view of an example user interface having two on/off switches. 
           [0027]      FIG. 12  is a schematic view of an example sterilization system having a pre-wash system. 
           [0028]      FIG. 13  is a perspective view of an example sterilization system having a pre-wash system. 
           [0029]      FIG. 14  is a perspective view of an example rinsing chamber. 
           [0030]      FIG. 15  is a schematic view of an example user interface associated with a sterilization system that includes a pre-wash system. 
           [0031]      FIG. 16  is a schematic view of an example user interface having two on/off switches associated with a sterilization system that includes a prewash system. 
           [0032]      FIG. 17  is a schematic view of an exemplary arrangement of operations for a method of sterilizing an instrument. 
       
    
    
       [0033]    Like reference symbols in the various drawings indicate like elements. 
       DETAILED DESCRIPTION 
       [0034]    Referring to  FIG. 1 , a sterilization system  100  includes a sterilization chamber  110  housing an ozone generator  120 . The ozone generator  120  produces ozone within the sterilization chamber  110  utilizing a cold plasma process, ultra violet light, a corona discharge, or an electrolytic ozone generation process (i.e., a process that splits water molecules into hydrogen (H 2 ), oxygen (O 2 ), and ozone (O 3 )). While the ozone generator  120  is described as using one of the foregoing processes, the ozone generator  120  may employ any suitable process that generates ozone. 
         [0035]    The ozone generator  120  includes an ozone-producing card ( FIG. 2 ) that, when energized, maintains a dielectric barrier discharge for the creation of a plasma field when generating ozone via a cold plasma process. When oxygen-concentrated air is exposed to a plasma field, the plasma splits the diatomic oxygen molecules into oxygen atoms, which then recombine in triplets to form ozone. While the ozone generator  120  may employ any of the processes disclosed above, the cold plasma process has the advantage of quickly producing greater quantities of ozone when compared to the other ozone generation processes. 
         [0036]    The sterilization chamber  110  is in fluid communication with an oxygen concentrator  130 . The oxygen concentrator  130  produces oxygen-concentrated air, which travels to the sterilization chamber  110 . The ozone generator  120  utilizes the oxygen-concentrated air to generate ozone via the cold plasma process described above. 
         [0037]    The sterilization chamber  110  is also in fluid communication with an air mover  140 . The air mover  140  exhausts air from the sterilization chamber  110  and recirculates the exhausted air through the sterilization chamber  110 . 
         [0038]    The sterilization system  100  includes a controller  150  in communication with the ozone generator  120 , the oxygen concentrator  130 , and the air mover  140 . In some implementations, the controller  150  includes a timer  154  that automatically terminates operation of the sterilization system  100  after a threshold period of time by directing the ozone generator  120  to cease plasma field generation, directing the oxygen concentrator  130  to cease production of air concentrated with diatomic oxygen molecules, and directing the air mover  140  to cease recirculation of the air within the sterilization chamber  110 . The controller  150  may additionally or alternatively include a processor  156  that controls multiple aspects of the sterilization process, including process initiation and termination and memory  158  for storing operational characteristics such as software and/or threshold operating parameters of the sterilization system  100 . 
         [0039]    The controller  150  communicates with the ozone generator  120  through communication line  152   a  to control aspects of the plasma field generation and communicates with the oxygen concentrator  130  through a communication line  152   b  to control aspects of the oxygen-concentrated air production. The controller  150  additionally communicates with the air mover  140  through a communication line  152   c  to control aspects of the air recirculation process. While the controller  150  is shown as being connected to the various components  120 ,  130 ,  140  via communication lines  152   a ,  152   b ,  152   c , the controller  150  could additionally or alternatively be in communication with the components  120 ,  130 ,  140  via a wireless connection. 
         [0040]    The sterilization system  100  optionally includes a user interface  160  in communication with the controller  150  through a communication line  152   d . Again, while the controller  150  is described and shown as being in communication with the user interface  160  via a communication line, the controller  150  could alternatively be in communication with the user interface  160  via a wireless connection. The user interface  160  may allow the user to control some aspects of the sterilization process such as, for example, process initiation. When the controller  150  includes a timer  156 , the user interface  160  may allow a user to set a threshold process time. Alternatively, the controller  150  may prevent a user from adjusting a threshold period of time at the user interface  160  or otherwise to ensure that the system  100  is not operated for a period of time greater than a predetermined threshold period of time. 
         [0041]    A power source  170  supplies power to the components of the sterilization system  100  through power lines  174 . The ozone generator  120  receives power from the power source  170  through power line  174   a . When the sterilization system  100  utilizes the cold plasma process to generate ozone, a power amplifier  172  amplifies the power from the power source  170 , along a first power line  174   a , to a level suitable for use by the ozone generator  120 . 
         [0042]    The power source  170  also supplies power to the oxygen concentrator  130  through a second power line  174   b , to the air mover  140  through a third power line  174   c , and to the controller  150  through a fourth power line  174   d . If the system  100  includes a user interface  160 , the power source  170  may supplies power to the user interface  160  as well. 
         [0043]    The sterilization system  100  optionally includes an exhaust system  180  that is designed to exhaust air from the sterilization chamber  110  through an ozone exhaust port  184 . An exhaust valve  182  may control air flow to the ozone exhaust port  184 . 
         [0044]      FIG. 2  illustrates an exemplary sterilization chamber  110 , which includes a body  112  and a lid  114  received by the body  112 . While the lid  114  is illustrated in  FIG. 2  as being pivotally coupled to the body  112 , the lid  114  may utilize an alternative design; it may be slidably attached to the body  112 , uncoupled (e.g., freely attachable and removable from the body  112 ), or otherwise configured to move between a closed position and an open position. In the closed position, the sterilization chamber  110  may provide the sterilization chamber  110  with a hermetic seal to prevent escapement of ozone from the sterilization chamber  110 . The lid  114  may be locked in the closed position during operation of the ozone generator  120  (e.g., during a sterilization process) using a locking mechanism  114   a  to prevent inadvertent or premature opening of the sterilization chamber  110  by a user. Additionally, the locking mechanism  114   a  may serve to draw the lid  114  closer to the body  112 , thereby improving the seal between the body  112  and the lid  114  and reducing the likelihood that ozone will escape the chamber  110 . Alternatively, the lid  114  of the sterilization chamber  110  may be provided without a locking mechanism  114   a.    
         [0045]    The sterilization chamber  110  houses a utensil tray  116 . In operation, a user deposits an instrument or utensil to be sterilized (not shown) into the utensil tray  116  and closes the lid  114  of the sterilization chamber  110 . Once the sterilization process has begun, the ozone generated by the ozone generator  120  sterilizes the instrument or utensil in the utensil tray  116 . 
         [0046]    The sterilization chamber  110  houses the ozone generator  120 . The ozone producing card discussed above may include a first plate and a second plate (neither shown), which are energized by the power source  170  through the first power line  174   a . The first plate and the second plate are constructed of stainless steel or another suitable material for transferring electrons between the plates and producing a plasma field when the power source  170  provides the plates with a voltage. A dielectric layer is positioned between the first plate and the second plate that maintains an even distribution of the electron transfer and prevents arcing. 
         [0047]    The ozone producing card generates a plasma field when the power source  170  provides an input voltage through the first power line  174   a . The applied voltage causes a current to be applied across both the top plate and the bottom plate, thereby producing plasma fields. Any voltage sufficient to power the ozone generator  120  may be utilized. For example, an input of approximately +3,500 V DC across the first plate and approximately −3,500 V DC across the second plate may be used to power the ozone generator  120 . 
         [0048]    The controller  150  optionally times the ozone generation and may turn the ozone generator  120  on and off at preset time intervals to pulse the discharge of the plasma fields. The controller  150  accomplishes this by pulsing the power feed from the power source  170  to the ozone generator  120 . 
         [0049]    The air mover  140  circulates gas into the sterilization chamber  110  at the gas inlet  112   a , through the sterilization chamber  110 , and out of the sterilization chamber  110  at the gas outlet  112   b . The gas entering the sterilization chamber  110  at the gas inlet  112   a  comprises a combination of the gas exhausted from the gas outlet  112   b  of the sterilization chamber  110  and gas concentrated with diatomic oxygen molecules produced by the oxygen concentrator  130 . The continuous supply of this mixture maintains an elevated oxygen concentration within the sterilization chamber  110 . 
         [0050]    The concentrated oxygen within the sterilization chamber  110  contacts the plasma fields generated by the ozone generator  120 . Upon contact, the diatomic oxygen molecules are split into oxygen atoms. The split oxygen atoms combine in groups of three oxygen atoms to form ozone within the sterilization chamber  110 . Driven by the oxygen-concentrated air entering the sterilization chamber  110  through the gas inlet  112   a  from the oxygen concentrator  130 , the ozone generator  120  maintains elevated concentrations of ozone inside the sterilization chamber  110 . It is advantageous to maintain a minimum of approximately 4,000 ppm of ozone within the sterilization chamber  110  in order to obtain sufficient sterilization. 
         [0051]    Referring to  FIG. 3 , a portable case  102  houses the sterilization system  100 . The portable case  102  includes a body (not shown) and a lid (not shown) that can be pivotally coupled to the body of the case  102 , slidably attached to the body of the case, uncoupled (e.g., freely attachable and removable), or otherwise configured to move between a closed position and an open position. When the lid is in the closed position, a user can easily and securely convey the sterilization unit  100  from one location to another. During times of conveyance, it is advantageous that the portable case  102  maintains the positioning of each component of the sterilization system  100 . Accordingly, the various components of the system  100  may be fixed relative to the body of the case  102  such that relative movement between the components of the system  100  and the body of the case  102  is restricted. 
         [0052]    Within the portable case  102 , the components of the sterilization system  100  are arranged in any manner that permits the system to operate as designed.  FIG. 3  illustrates one such exemplary arrangement. This arrangement may be predetermined based on depressions or other location features of the case body that ensure each component of the system  100  is properly installed in a predetermined location within the case  102 . In the illustrated configuration, the oxygen concentrator  130  and the air mover  140  are disposed relative to the gas inlet  112   a  on the body  112  of the sterilization chamber  110 . 
         [0053]    The gas inlet piping/tubing  118   a  fluidly connects the oxygen concentrator  130  and the air mover  140  to the gas inlet  112   a  on the body  112  of the sterilization chamber  110 .  FIG. 3  illustrates an exemplary implementation in which a single gas inlet  112   a  receives the output from both the oxygen concentrator  130  and the air mover  140 . 
         [0054]    The oxygen concentrator  130  produces oxygen-concentrated air and injects the gas into the gas inlet piping/tubing  118   a . In the gas inlet piping/tubing  118   a , the oxygen-concentrated air combines with the recirculating ozone-concentrated air from the air mover  140 . In one configuration, the oxygen concentrator  130  supplies approximately 1.5 liters per minute of gas flow having an oxygen concentration of at least seventy-five percent in order to maintain the ozone concentration at approximately 4,000 ppm in the sterilization chamber  110 . 
         [0055]    The air mover  140  optionally includes a pneumatic pump or any other mechanical system or device capable of recirculating sufficient quantities of air through the sterilization chamber  110 . The air mover  140  is in fluid communication with the gas outlet  112   b  on the body  112  of the sterilization chamber  110  and extracts ozone-concentrated air from the sterilization chamber  110 , which travels through the gas outlet piping/tubing  118   b  and is either exhausted or is recirculated. 
         [0056]    The ozone exhaust port  184  releases from the sterilization system  100  a portion of the ozone-concentrated air, which the air mover  140  extracted from the sterilization chamber  110 . An exhaust valve  182  controls the flow rate of this ozone-concentrated air released at the ozone exhaust port  184 . 
         [0057]    The air mover  140  recirculates the remainder of the extracted ozone-concentrated air into the gas inlet  112   a  on the body  112  of the sterilization chamber  110 . It is advantageous to maintain a recirculation rate of the ozone-concentrated air at approximately five liters per minute in order to maintain the ozone concentration at approximately 4,000 ppm in the sterilization chamber  110 . 
         [0058]    The portable case  102  also houses the controller  150 . In the exemplary implementation of  FIG. 3 , the controller  150  receives continuous power from the power source  170  through the fourth power line  174   d.    
         [0059]    In the configuration illustrated in  FIG. 3 , the communication lines  152  (shown in  FIG. 1 ) extend within the portable case  102  from the controller  150  to various components of the sterilization system  100  allowing the controller  150  to oversee and/or control various aspects of the sterilization operation. The aspects of the operation overseen and/or controlled by the controller  150  include, but are not limited to, operation initiation and operation termination. For clarity purposes, the communication lines  152  are not shown in  FIG. 3 . 
         [0060]    On/off switches  168  optionally allow a user to selectively turn on and off components of the sterilization system  100 . For example,  FIG. 3  illustrates an exemplary implementation utilizing one switch  168   b  to turn on and off the ozone generator  120  and a second switch  168   c  to turn on and off the oxygen concentrator  130  and the air mover  140 . 
         [0061]    The power source  170  may include a battery that is disposed within the portable case  102  of the sterilization system  100 . In the alternative, the sterilization system  100  can utilize an external power source, which can either be portable or fixed. The first power line  174   a  from the power source  170  to the ozone generator  120  includes a power amplifier  172  and powers the ozone generator  120 . The second power line  174   b  from the power source  170  powers the oxygen concentrator  130 , while the third power line  174   c  from the power source  170  powers the air mover  140 . 
         [0062]    Referring to  FIG. 4 , the sterilization system  100  is shown as utilizing one or more measuring devices  122 ,  132 ,  134 ,  142 . Communication lines  152  send output signals from the one or more measuring devices  122 ,  132 ,  134 ,  142  to the controller  150 . The controller may utilize the signals from these one or more measuring devices  122 ,  132 ,  134 ,  142  to display information on the user interface  160  and/or to adjust the operation of other components of the sterilization system  100 . The power source  170  is in electrical communication with and powers the one or more measuring devices  122 ,  132 ,  134 ,  142 . 
         [0063]    The measuring device  122  may be an ozone meter  122  that measures ozone concentrations within the sterilization chamber  110 . The ozone meter  122  communicates the ozone concentration to the controller  150  through communication line  152   e . The user interface  160  optionally displays the ozone concentration to permit a user to readily ascertain the ozone concentration within the chamber  110 . The controller  150  may receive information from the ozone meter  122  regarding the concentration measurements to allow the controller  150  to adjust operation of the various components of the sterilization system  100  such as, for example, the ozone generator  120 , the oxygen concentrator  130 , and the air mover  140 . Such adjustments by the controller  150  aim to implement an increase or decrease to the ozone concentration in the sterilization chamber  110  to maintain the ozone concentration within the chamber  110  at a predetermined concentration (i.e., at or above approximately 4,000 ppm in one configuration). 
         [0064]    The measuring device  132  may be an oxygen meter  132  that measures at least one of an air flow rate from the oxygen concentrator  130  or a concentration of diatomic oxygen molecules within the air flowing from the oxygen concentrator  130 . The oxygen meter  132  communicates its measurements to the controller  150  through a communication line  152   f . As with the ozone concentration meter  122 , the user interface  160  may display the measurements received from the oxygen meter  132 . The controller  150  may receive the measurements from the oxygen meter  132  and may adjust operation of the oxygen concentrator  130  through the communication line  152   b . The communicated operational changes aim to implement an increase or a decrease of at least one of the air flow rate from the oxygen concentrator  130  or the concentration of diatomic oxygen molecules within the air flowing from the oxygen concentrator  130  to maintain the ozone concentration within the chamber  110  at a predetermined concentration. 
         [0065]    The measuring device  134  may be an oxygen concentration meter  134  that measures the concentration of diatomic oxygen molecules within the sterilization chamber  110 . The oxygen concentration meter  134  communicates the oxygen concentration to the controller  150  through a communication line  152   g . Once again, the user interface  160  may display the concentration received from the oxygen concentration meter  134 . The controller  150  may utilize the oxygen concentration measurements to adjust operation of the oxygen concentrator  130  through the communication line  152   b . The communicated operational changes aim to implement an increase or decrease in the concentration of diatomic oxygen molecules within the sterilization chamber  110  to once again maintain the ozone concentration within the chamber  110  at a predetermined concentration. 
         [0066]    The measuring device  142  may be an air flow meter  142 , which is disposed on the gas piping/tubing  118 . The air flow meter  142  measures the air recirculation flow rate through the air mover  140  and communicates the air recirculation flow rate to the controller  150  through communication a line  152   h . As with the measuring devices  122 ,  132 ,  134 , the user interface  160  may display the flow rate to communicate the flow rate to the user. The controller  150  may also utilize the flow rate measurements to adjust the speed of the air mover  140  to increase or decrease the flow rate. Specifically, the controller  150  may send a signal to the air mover  140  via the communication line  152   c  to adjust an output of the air mover  140  based on the current ozone concentration in the chamber  110 . 
         [0067]    As set forth above, the controller  150  receives information from the various measurement devices  122 ,  132 ,  134 ,  142  for use by the controller  150  in controlling the various components  120 ,  130 ,  140  of the sterilization system  100  all in an effort to maintain an ozone concentration in the chamber  110  at a predetermined level. The controller  150  may additionally receive various user-inputs to aid or direct the controller  150  in controlling the various components  120 ,  130 ,  140 . For example, a user may change the desired ozone concentration by adjusting the predetermined value above or below 4000 ppm. The controller  150  may receive this information along with information from the measurement devices  122 ,  132 ,  134 ,  142  and may control the various components  120 ,  130 ,  140  based on this information. 
         [0068]    An error warning is optionally displayed on the screen  162  of the user interface  160  when any one of the measurements reaches a preset high or low level. An additional or different warning may be displayed when the controller  150  is unable to direct the sterilization system  100  to bring the measurements within the preset levels. 
         [0069]    Referring to  FIG. 5 , in some implementations, an exhaust system  180  releases ozone-concentrated air from the sterilization chamber  110  and the sterilization system  100 . The air mover  140  extracts ozone-concentrated air from the gas outlet  112   b  on the body  112  of the sterilization chamber  110 . The air mover  140  recirculates a portion of this extracted air back into the sterilization chamber  110  through a gas inlet  112   a , and the exhaust system  180  exhausts the remainder of the extracted air. The exhausted ozone-concentrated air separates from the recirculated air prior to reaching the air mover  140  and exits the sterilization system  100  at the ozone exhaust port  184 . 
         [0070]    An exhaust valve  182  optionally controls the flow of the ozone-concentrated air exiting the sterilization system  100  at the ozone exhaust port  184 . In the configuration of the exhaust system  180  of  FIG. 5 , the exhaust valve  182  modulates between fully open and fully closed. An exhaust meter  186 , located downstream of the exhaust valve  182 , measures the flow of the ozone-concentrated air to the ozone exhaust port  184 . In other configurations, the exhaust meter  186  is located upstream of the exhaust valve  182 . 
         [0071]    The exhaust meter  186  communicates the flow measurement to the controller  150  through a communication line  152   m . The user interface  160  optionally displays the flow measurement. The controller  150  utilizes the flow measurement to communicate a change in position of the exhaust valve  182  through a communication line  152   n  in order to increase or decrease the flow rate of the ozone-concentrated air to the ozone exhaust port  184 . The power source  170  provides power through power line  174   h  for automatic modulation of the exhaust valve  182  and also powers the exhaust meter  186 . 
         [0072]    Other configurations of the exhaust system  180  do not include an exhaust meter  186 . For example, in one such system, the exhaust valve  182  remains open during operation of the sterilization system  100  unless a user manually closes the exhaust valve  182 . In another exemplary configuration of the exhaust system  180 , the exhaust valve  182  opens and closes as directed by a signal from the controller  150  through communication line  152   n , but the exhaust valve  182  does not modulate. In this implementation, the power source  170  provides power for automatic opening and closing of the exhaust valve  182 . 
         [0073]    Whether or not the exhaust system  180  includes an exhaust meter  186 , the controller  150  may maintain an exhaust flow rate of ozone-concentrated air at approximately 0.5 liters per minute. Maintaining a flow rate of approximately 0.5 liters per minute relieves excessive pressure that has accumulated within the sterilization chamber  110  and the gas piping/tubing  118 . 
         [0074]    As discussed above, the user interface  160  includes the screen  162  (e.g., liquid-crystal display (LCD), touch display screen, etc.) that displays one or more views  164 , each of which optionally includes one or more user interface buttons  166 .  FIG. 6  illustrates an example ready view  164   a . The ready view  164   a  includes a ‘GO’ button  166   a , which allows the user to initiate operation of the sterilization system  100 . 
         [0075]      FIG. 7  illustrates an example operation view  164   b  that includes one or more operation metrics. The operation metrics may include, but are not limited to, a cycle time (e.g., a time remaining in a sterilization cycle), an Ozone level in the sterilization chamber  110 , an Oxygen level (e.g., percentage of Oxygen) in the sterilization chamber  110 , an Oxygen delivery rate (e.g., in L/min.), and/or a gas recirculation rate (e.g., in L/min.) through the sterilization chamber  110 . 
         [0076]      FIG. 8  illustrates an example operation complete view  164   c . The operation complete view  164   c  may include one or more words and/or a glyph indicating to the user that the sterilization operation is complete. Moreover, the operation complete view  164   c  may include instructions indicating how the user may retrieve the sterilized instrument from the sterilization chamber  110  without compromising the sterilized nature of the instrument. 
         [0077]      FIG. 9  illustrates an example error view  164   d . The error view  164   d  may include one or more words and/or a glyph indicating to the user that the sterilization operation experienced an error and/or that the sterilization operation is not complete. In the example shown, the error view  164   d  indicates that the sterilization operation was stopped, that the sterilization operation is not complete, and the operation metrics at the time the operation stopped. Other information can be provided as well or in lieu of that shown in the example. 
         [0078]    Referring to  FIGS. 10-11 , in some implementations, the user interface  160  includes one or more on/off switches  168 .  FIG. 10  illustrates an example user interface  160  with a single on/off switch  168   a  to initiate full operation of the sterilization system  100 .  FIG. 11  illustrates an example user interface  160  with a first on/off switch  168   b  to initiate operation of the ozone generator  120  and a second on/off switch  168   c  to initiate operation of the oxygen concentrator  130  and the air mover  140 . 
         [0079]    Referring to  FIGS. 12-16 , in some implementations, the sterilization system  100  includes a rinsing system  190 . The rinsing system  190  enables the sterilization of a rinse fluid within a fluid reservoir  192  and the application of the sterilized rinse fluid to an instrument or utensil. The application of the sterilized rinse fluid to the instrument or utensil may serve to remove bio burden from the instrument or utensil, sterilize the instrument or utensil, or accomplish both removal of bio burden and sterilization. 
         [0080]    Referring specifically to  FIG. 12 , the user simply deposits the instrument or utensil into the utensil tray  116  and closes the lid  114  of the sterilization chamber  110 . A rinse fluid pump  194  initiates a flow of rinse fluid through the rinse fluid piping/tubing  196 . The rinse fluid enters the sterilization chamber  110 , and one or more nozzles  198  spray the rinse fluid at the utensil tray  116  to remove the bio burden from the instrument or utensil. This process may be referred to as a pre-wash cycle. After the rinsing system  190  concludes the pre-wash cycle, the ozone generator  120 , oxygen concentrator  130 , and air mover  140  commence operation to begin sterilization. 
         [0081]    Alternatively, the implementation of the rinsing system  190  illustrated in  FIG. 12  may be utilized to apply the rinse fluid after the sterilization process utilizing the ozone-concentrated air has occurred within the sterilization chamber  110 . In this case, the rinsing system  190  applies to sterilized fluid to effectuate additional sterilization of the instrument or utensil. This utilization of the rinsing system  190  may prove desirable because, under some conditions, ozone-concentrated fluid allows for more effective sterilization than ozone-concentrated air. 
         [0082]    Referring specifically to  FIGS. 13-14 , in some implementations of the sterilization system  100 , the rinsing system  190  may further include a rinsing chamber. Similar to the implementation shown in  FIG. 12 , the implementation of  FIGS. 13-14  may be utilized to effectuate a pre-wash cycle or can be utilized after the sterilization process within the sterilization chamber  110  to effectuate additional sterilization of the instrument or utensil. 
         [0083]    The user deposits the instrument or utensil into the utensil tray  216  and closes the lid  214  of the rinsing chamber  210 . A rinse fluid pump  194  initiates a flow of rinse fluid through the rinse fluid piping/tubing  196 . The rinse fluid enters the rinsing chamber  210 , and one or more nozzles  198  spray the rinse fluid at the utensil tray  216  to apply the rinse fluid to the instrument or utensil. 
         [0084]      FIG. 14  illustrates an exemplary rinsing chamber  210 , which includes a body  212  and a lid  214  received by the body  212 . While the lid  214  is illustrated in  FIG. 14  as being pivotally coupled to the body  212 , the lid  214  may utilize an alternative design; it may be slidably attached to the body  212 , uncoupled (e.g., freely attachable and removable from the body  212 ), or otherwise configured to move between a closed position and an open position. The lid  214  may be locked in the closed position during operation of rinsing system  190  using a locking mechanism  214   a  to prevent inadvertent or premature opening of the rinsing chamber  210  by a user. Alternatively, the lid  214  of the rinsing chamber  210  may be provided without a locking mechanism  214   a.    
         [0085]    The body  212  of the rinsing chamber  210  defines two openings  212   a ,  212   b  through which the rinse fluid piping/tubing  196  enters to the interior of the rinsing chamber  210 . Within the interior of the rinsing chamber  210 , the rinse fluid piping/tubing  196  terminates at two nozzles  198 , which apply the rinse fluid to the instrument or utensil as desired. The quantity of nozzles  198  within the interior of the rinsing chamber  210  may vary from one to more than two depending of the desired spray pattern. While  FIG. 14  illustrates a body  212  of the rinsing chamber  210  with two openings  212   a ,  212   b , the quantity of openings may vary to correspond to the quantity of nozzles  198 . 
         [0086]    Referring again to  FIGS. 12-16 , the fluid reservoir  192  provides the rinse fluid to the rinse fluid pump  194 . The rinse fluid piping/tubing  196  may include a filter screen, trough, or some other type of cleanout  197  to prevent suspended solids in the fluid reservoir  192  from reaching the rinse fluid pump  194 . The power source  170  powers the rinse fluid pump  194  through a power line  174   e.    
         [0087]    Ozone disinfects the fluid in the fluid reservoir  192 . Ozone-concentrated air from the sterilization chamber  110  travels to the fluid reservoir  192  through the ozone supply piping/tubing  202 .  FIGS. 12-13  illustrate a configuration in which the ozone-concentrated air comes from the exhaust system  180  piping/tubing. In other configurations, the ozone-concentrated air may be supplied to the fluid reservoir  192  by the air mover  140 . Alternatively, ozone-concentrated air may travel to the fluid reservoir  190  directly from the ozone exhaust port  184 , directly from the sterilization chamber  110 , from any point on the gas piping/tubing  118 , or from any other location with access to the ozone-concentrated air. 
         [0088]    Ozone-concentrated air enters the fluid reservoir  192  and impregnates the fluid, which, in turn, sterilizes the fluid. Upon completion of the fluid sterilization, the rinse fluid pump  194  commences the rinsing process by supplying sterilized fluid from the fluid reservoir  192  to the one or more nozzles  198 . 
         [0089]    In the implementation of  FIG. 12 , the ozone supply valve  200 , disposed on the ozone supply piping/tubing  202 , moves between an open and a closed state. Either the user manually opens and closes the ozone supply valve  200  or an open/close signal supplied by the controller  150  through the communication line  152   j  automatically initiates opening and closing of the ozone supply valve  200 . If the ozone supply valve  200  operates automatically upon receiving a signal from the controller  150 , a power line  174   g  provides the ozone supply valve  200  with power from the power source  170 . Accordingly, the ozone supply valve  200  remains open only during sterilization of the fluid in the fluid reservoir  192 . In the implementation of  FIG. 13 , the ozone supply valve  200  and the exhaust valve  182  are illustrated as combined within a single three-way valve. This permits the ozone-concentrated air exhausted from the gas outlet piping/tubing  118   b  to travel to either the ozone exhaust port  184  or the fluid reservoir  192 , depending upon the position of the three-way valve. In order to sterilize the fluid within the fluid reservoir  192 , the positioning of the three-way valve would direct the ozone-concentrated air to the fluid reservoir  192  through the ozone supply piping/tubing  202 . The three way valve can be manual, as shown in  FIG. 13 , or automatic, which would utilize control signals from the controller  150  through communication line  152   j  and power from the power source  170  through power line  174   g . Although the implementation of  FIG. 12  illustrates one configuration of the ozone supply valve  200  and  FIG. 13  illustrates another configuration, each different configuration of the ozone supply valve  200  can be utilized in each implementation of the rinsing system  190 , interchangeably. 
         [0090]    Turning back to the general aspects of the rinsing system  190 , the ozone generator  120  drives the sterilization of the fluid in the fluid reservoir  192  by generating the ozone-concentrated air utilized to impregnate and sterilize the fluid. To permit proper functioning of the ozone generator  120 , the oxygen concentrator  130  also generates a gas rich in diatomic oxygen molecules and the air mover  140  circulates air through the sterilization chamber  110 . During the sterilization process of the fluid in the fluid reservoir  192 , the exhaust valve  182  remains in a closed position to direct sufficient ozone-concentrated air to the fluid reservoir  192 . 
         [0091]    The rinsing system  190  may include a sterilized fluid outlet  204 . The user or the controller  150  directs the sterilized fluid outlet  204  to discharge sterilized fluid from the fluid reservoir  192  for external use by the user. Although the implementation of  FIG. 12  includes a sterilized fluid outlet  204  and the implementation of  FIG. 13  does not include a sterilized fluid outlet  204 , either implementation—depending upon the needs of the user—could include or not include a sterilized fluid outlet  204 . 
         [0092]    In some implementations, the fluid reservoir  192 , the rinse fluid pump  194 , the rinse fluid piping/tubing  196 , the ozone supply valve  200 , and the ozone supply piping/tubing  202  are disposed within the portable case  102  of the sterilization system  100 . If the rinsing system  190  includes a rinsing chamber  210 , the rinsing chamber  210  may also disposed within the portable case  102 . 
         [0093]    In some implementations, the rinsing system  190  includes a fluid reservoir  192  for the sterilization of fluid, but does not include a rinse fluid pump  194 , one or more nozzles  198 , or a rinsing chamber  210 . In these implementations, the user submerges the utensil or instrument in the fluid reservoir  192  to remove bio burden before inserting the utensil or instrument into the utensil tray  116  for sterilization. Such implementations optionally include a sterilized-fluid outlet  204 . 
         [0094]    As illustrated in  FIG. 12 , the sterilization chamber  110  optionally houses a debris scraper  116   a . During the pre-wash cycle, bio burden may accumulate on the utensil tray  116 . The debris scraper  116   a  removes bio burden from the utensil tray  116 .  FIG. 12  illustrates an automatic debris scraper  116   a  that receives power from power source  170  through a power line  174   f  and a signal to operate from the controller  150  through communication line  152   k . Alternatively, the design of the debris scraper  116   a  may allow for manual operation only. In these implementations including a manual debris scraper  116   a , the debris scraper  116   a  may be attached within the sterilization chamber  110  or may be stored elsewhere within the portable case  102 . 
         [0095]    In the implementation of  FIG. 14 , the rinsing chamber  210  is shown without a debris scraper  116   a . However, similar to the sterilization chamber  110  in the implementation of  FIG. 12 , the rinsing chamber  210  may be provided with a manual or an electric debris scraper  116   a  to clean bio burden from the utensil tray  216  within the rinsing chamber  210 . 
         [0096]      FIG. 15  illustrates an example ready view  164   e  shown on the screen  162  of the user interface  160  for a sterilization system  100  that includes a rinsing system  190 . To begin the pre-wash and sterilization processes, the user presses a ‘GO’ button  166   a . To receive sterilized fluid, which may consist of water or some other fluid, from the sterilized fluid outlet  204 , the user presses a ‘WATER’ button  166   b.    
         [0097]    In alternative implementations, the user interface  160  optionally provides the user with an option to initiate the sterilization process without the pre-wash process or to initiate the pre-wash process without the sterilization process. 
         [0098]    Referring to  FIG. 16 , in some implementations, the user interface  160  includes one or more on/off switches  168 .  FIG. 16  illustrates an example user interface  160  with a first on/off switch  168   d  to initiate the pre-wash process and a second on/off switch  168   a  to initiate the sterilization process. Other alternative implementations optionally include one or more switches allowing the user to control different processes or components of the sterilization system  100  or, in particular, of the rinsing system  190 . 
         [0099]      FIG. 17  illustrates an exemplary arrangement of operations for a method  1700  of sterilizing an instrument. At block  1702 , the method  1700  includes receiving an instrument in a sterilization chamber  110 . At block  1704 , the method  1700  includes generating at least one plasma field in the sterilization chamber  110  using an ozone generator  120  disposed in the sterilization chamber  110  to generate ozone. At block  1706 , the method  1700  includes delivering oxygen-concentrated air to the sterilization chamber  110  (e.g., via an oxygen concentrator  130 ). At block  1708 , the method  1700  includes circulating the ozone within the sterilization chamber  110  (e.g., via an air mover  140 ). 
         [0100]    A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other implementations are within the scope of the following claims.