Abstract: In the treatment of articles with a sterilant gas such as an alkylene oxide, and the circulation of the gas throughout a treatment chamber containing the articles to be treated, a gas circulating system completely devoid of electrical contacts, switches, electrical motors and other potentially dangerous electrical components which could cause explosive ignition of the sterilant gas. The circulation system includes a fluid-driven turbine-like impeller completely isolated from the sterilant gas, and drivingly coupled to a fan blade which serves to force the gas through conduits and to circulate and recycle the sterilant gas throughout the treatment chamber. In a second embodiment of the invention a magnetically coupled drive is used to actuate the sterilant-circulating fan.
Type:
Grant
Filed:
September 5, 1980
Date of Patent:
November 17, 1981
Assignee:
Griffith Laboratories U.S.A., Inc.
Inventors:
Donald E. Alguire, Robert Bennett, Norbert Kotulla, Anthony C. Yeung
Abstract: Biocidal gas sterilization methods and apparatus are disclosed in which goods are heated and moisturized prior to addition of the sterilizing gas utilizing repressurization after initial evacuation to provide drive power for the conditioning vapor and improve conditioning efficiency. After initial evacuation to a selected subatmospheric pressure level, the chamber is repressurized with a conditioning vapor comprising steam to a subatmospheric pressure level corresponding approximately to desired sterilizing temperature, then the chamber is held with evacuating and vapor injecting interrupted for a predetermined interval; this sequence of steps is repeated a selected number of times; and, conditioning to various sterilizing temperatures is available. Initial evacuation can be accompanied by intermittent injection of conditioning vapor. No chamber measurement of temperature or relative humidity is required for conditioning control and conditioning vapor injection is free of flow rate control requirements.
Abstract: A system for producing a stream of humidified sterilizing gas for sterilizing objects such as the water systems of space vehicles and the like. The system includes a source of sterilant gas which is fed to a mixing chamber having inlet and outlet ports. Water is carried in the mixing chamber with the level of the water only partially filling said mixing chamber so as to provide an empty space adjacent the top of the chamber. A heater is provided for heating the water in said chamber producing a humidified atmosphere. The sterilant gas is fed through an arcuate shaped tubular member connected to the inlet port of the mixing chamber for producing a vortex type of flow of sterilant gas into the chamber for being humidified. A tubular member extends from the mixing chamber for supplying the humidified sterilant gas to the object for being sterilized. Scrubbers are provided for removing the sterilant gas after use.
Type:
Grant
Filed:
June 8, 1979
Date of Patent:
February 10, 1981
Assignee:
The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
Inventors:
Coleman J. Bryan, Edward E. Wright, Jr., Clyde V. Moyers
Abstract: Biocidal gas sterilization methods and apparatus are disclosed in which goods are heated and moisturized prior to addition of the sterilizing gas utilizing repressurization after initial evacuation to provide drive power for the conditioning vapor and improve conditioning efficiency. After initial evacuation to a selected subatmospheric pressure level, the chamber is repressurized with a conditioning vapor comprising steam to a subatmospheric pressure level corresponding approximately to desired sterilizing temperature, then the chamber is held with evacuating and vapor injecting interrupted for a predetermined interval; this sequence of steps is repeated a selected number of times; and, conditioning to various sterilizing temperatures is available. Initial evacuation can be accompanied by intermittent injection of conditioning vapor. No chamber measurement of temperature or relative humidity is required for conditioning control and conditioning vapor injection is free of flow rate control requirements.
Abstract: Conditioning of goods for subsequent sterilization with a biocidal agent in a sealable chamber includes removal of air, and moistening and heating the goods to the desired temperature levels. Controlled evacuation of the chamber and coordinated admission of conditioning vapor into the chamber provides cyclic variations in chamber pressure between preselected subatmospheric pressures to subject goods in the chamber to a plurality of cyclic subatmospheric pressure pulses. The time required for the cyclic pressure variations is responsive to load characteristics, including heat and moisture absorption characteristics of the goods being conditioned, and is independent of prescribed times or direct measurement of load temperature. The subatmospheric pressure levels are selected based on the temperature-pressure relationship of the conditioning vapor so that chamber temperature during cyclic pulsing does not exceed the desired sterilization temperature.
Abstract: Conditioning of goods for subsequent sterilization with a biocidal agent in a sealable chamber includes removal of air, and moistening and heating the goods to the desired temperature levels. Controlled evacuation of the chamber and coordinated admission of conditioning vapor into the chamber provides cyclic variations in chamber pressure between preselected subatmospheric pressures to subject goods in the chamber to a plurality of cyclic subatmospheric pressure pulses. The time required for the cyclic pressure variations is responsive to load characteristics, including heat and moisture absorption characteristics of the goods being conditioned, and is independent of prescribed times or direct measurement of load temperature. The subatmospheric pressure levels are selected based on the temperature-pressure relationship of the conditioning vapor so that chamber temperature during cyclic pulsing does not exceed the desired sterilization temperature.
Abstract: A reference electrode having a first tubular member, an elongate electrode element disposed within the tubular member, and a second tubular member disposed within the first tubular member to protrude out one end thereof is sterilized by aspirating through the first tubular member into the second tubular member a solution of HEMA and a salt dissolved in a solvent, evaporating the solvent, exposing the interior and exterior surfaces of the electrode to ethylene oxide gas, aerating the electrode, and immersing the electrode in a solution of said salt until the osmolality of the solution within the electrode and of the solution without the electrode is substantially the same.
Abstract: A method of sterilizing with a mixture of ethylene oxide gas and an inert gas which makes possible reuse of the ethylene oxide for an indefinite number of successive sterilization cycles. The gas mixture is refortified with ethylene oxide when necessary. A portion of it is periodically vented when the increasing proportion of air produces a mixture which approaches the region of flammability of the mixture and is replaced with the inert gas to reduce the proportion of air in the mixture.