Hydrogen peroxide indicators for validation of isolator sterilization with peracetic acid

Due to the lack of chemical indicators available on the market for peracetic acid, it is not possible to guarantee the exposure to the gas when sterilizing an isolator. Whereas some defects (i.e errors of connexion with isolators / errors of sterilizing product) are not detectable with the parameters recorded by the sterilizators (i.e. duration, T°, gas volume consumption). Our objective was to check if chemical indicators marketed for hydrogen peroxide sterilization may be used for peracetic acid sterilization based on the fact that peracetic solutions contains also an amount of hydrogen peroxide. 3 types of chemical indicators were evaluated (2 strips from Steris (VHP® indicator and Steraffirm® and one from Bioquell (HPV-CI®), 5 Isolators units were evaluated (1 isolator 3 gloves and 1 emergency container from Getinge coupled to a MAN ®230 sterilisator delivering 70 ml/h peracetic acid , 1 working isolator 4 gloves, 1 standard pass-through and 1 emergency pass through from JCE coupled to a STELEC sterilisator delivering 60 ml/h peracetic acid). Sterilizing agent was Perform® select soproper (schülke) for all the units investigated. Result are given in the following table

Steraffirm® strips and HPV-CI® can be used as chemical indicator of exposure for peracetic acid sterilisation in our investigated conditions. The use of this chemical indicators in other sterilization conditions (i.e. different sterilizing agent), should be validated. The possible use of these indicators in daily practice can be easily validated during the initial qualification steps of the sterilization process.