sterile processing
sterile processing
By Susan Klacik , BS , CRCST , CIS , CHL , ACE , FCS
Sterile Processing Leaders , Do You Know How ST108 Affects Device Processing ?
ST108 addresses various levels of water quality and steam purity suitable for medical device processing and describes water treatment processes that can be used to produce water that meets quality requirements for medical device processing .”
It is essential that sterile processing ( SP ) professionals have ready access to the latest standards and guidelines and work to ensure that recommended best practices are understood and consistently followed . One of the most anticipated standards to be released was ANSI / AAMI ST108:2023 Water for the processing of medical devices , an upgrade from the water quality technical information report TIR 34 .
Water is a primary resource used for medical device processing , relied upon heavily in the cleaning process and to generate steam for sterilization . The risks associated with poor-quality water being used on a medical device during processing can result in ineffective cleaning and disinfection , device malfunction during use , toxic residues remaining on a device , patient infection , and pyrogenic reactions . ST108 addresses various levels of water quality and steam purity suitable for medical device processing and describes water treatment processes that can be used to produce water that meets quality requirements for medical device processing . It is an especially valuable resource because it addresses water quality at the point-of-use and for cleaning , rinsing , disinfecting and sterilizing medical devices .
Water-type differences
ST108 defines three types of water quality and provides the specific performance qualification levels of water quality for each . All levels are required to meet the water quality measurement values as defined in this standard . The three levels include :
Utility water — Water that comes from the tap and is the type recommended for cleaning medical devices . It can also be used for the initial rinse to remove soil loosened by the cleaning process and for removing cleaning agent residues . This water may require further treatment at the facility to achieve the specified water quality . This water is mainly used for flushing , washing and intermediate rinsing ( rinsing between cleaning and disinfection ). Note : Tap water may not meet the requirements of utility water as defined in ST108 . For that reason , tap water used in SP areas should be analyzed to determine its characteristics and whether treatment is needed to meet the requirements for utility water . The water treatment system manufacturer should be consulted to validate that the treatment process will be adequate for the specific characteristics of the incoming tap water .
Critical water — Water that meets the water quality measurement values as described in AAMI standards . To achieve these values , water generally requires a level of purification that can only be achieved by removing ionic contaminants from the water ( this process is referred to as reverse osmosis or deionization ). There are instances where both technologies may be used together to meet the water characteristics needed to be classified as critical water . There will also be other forms of treatment that can be found with systems that produce critical water . Softening , carbon filtration , coarse filtration , ultrafiltration , UV lighting are some of the technologies that could be found with these systems . This water is mainly used for the final rinse after high-level disinfection and / or for the final rinse for critical devices prior to sterilization . For automated endoscope reprocessors ( AERs ), it is important to understand the equipment IFU to ensure equipment compatibility with critical water . Note : Much of today ’ s equipment is not designed to handle the corrosive nature of critical water ; therefore , utility water is specified for the final rinse .
Steam — Vaporized water produced by a centralized boiler or a generator / heat exchanger near the sterilizer . Most steam used in a Sterile Processing department ( SPD ) is piped from a centralized system for many other purposes ( known as plant or house steam ). The steam is generated in this centralized system and transferred through piping to the sterilizer . Other types of steam are located close to the sterilizer ; based on the design of the equipment and the respective IFU , utility or critical water may be used in a pure steam generator .
Water quality for SP equipment , core functions
ST108 provides water quality factors for washer-disinfectors . Washer-disinfectors are often equipped with at least one control valve for hot water and another for cold water . A separate control valve is for the final rinse .
Ultrasonic ( sonic ) cleaners are also useful for removing soil from joints , crevices , lumens and other areas that are difficult to clean by other methods . Utility water can be used unless otherwise indicated by the ultrasonic or medical device manufacturer ’ s written instructions for use ( IFU ). The key water-quality factors to consider for ultrasonic cleaning include water hardness and physical appearance ( color , clarity and absence of particulates / sediment ). If the ultrasonic www . healthcarehygienemagazine . com • october 2023
21