Abstract
The control of microbial load on surfaces of research and animal labs as well as of hospital and production rooms is an everyday challenge. Surface sanitization or disinfection of production equipments and rooms by wiping with chemicals is a time-consuming procedure. Its validation is very intricate. Alternatively, fumigation allows overcoming many critical aspects of wiping in both procedure and validation. Moreover, the use of nebulized hydrogen peroxide (H(2)O(2)) of moderate concentration resolves remaining reservations as to toxicity, corrosion, and persistence. This paper presents major criteria for the effective use of fumigation with emphasis on a new H(2)O(2) procedure. Focus is set to the proper and simplified validation of the process using standardized biological indicators with defined concentrations of the test organism Geobacillus stearothermophilus. Extensive test results from design of experiment studies support the knowledge of the sanitization process and allows for choosing critical process parameters within well known boundaries. Target values of total kill of 10(4) to 10(6) cfu per carrier are reproducibly reached. The new concept has then been applied to the decontamination of small rooms as well as to large multi-rooms up to 750 m(3). These case studies are described and illustrate the wide field of application of the technique proposed. The concept presented for validation of the sanitization procedure overcomes the problems associated with conventional surface disinfection validation. It allows for considerable more safety at greatly reduced cost and work.Lay abstract
Microbial load on surfaces of research and animal labs as well as of hospital and production rooms has to be maintained low to support aseptic conditions. Surface sanitization or disinfection by wiping with chemicals is time-consuming and its validation intricate. Fumigation as alternative overcomes many critical aspects of wiping in both procedure and validation. Nebulized hydrogen peroxide (H(2)O(2)) of moderate concentration has particular advantages in respect to toxicity, corrosion, and persistence. This paper presents major criteria for the effective use of fumigation with emphasis on a new H(2)O(2) procedure. Focus is set to the proper and simplified validation of the process using standardized biological indicators. Test results from design of experiment studies support the knowledge of the sanitization process and allow choosing optimal process parameters. A total kill of 10(4) to 10(6) cfu per carrier is reproducibly reached. The new concept has then been applied to decontamination of rooms up to 750 m(3). These case studies and benefits are described and illustrate the wide field of application of the technique proposed. The concept presented simplifies validation of the sanitization procedure and allows for considerable more safety at greatly reduced cost and work.