Can sterilization of disposable face masks be an alternative for imported face masks? A nationwide field study including 19 sterilization departments and 471 imported brand types during COVID-19 shortages.

BACKGROUND: Face masks, also referred to as half masks, are essential to protect healthcare professionals working in close contact with patients with COVID-19-related symptoms. Because of the Corona material shortages, healthcare institutions sought an approach to reuse face masks or to purchase new, imported masks. The filter quality of these masks remained unclear. Therefore, the aim of this study was to assess the quality of sterilized and imported FFP2/KN95 face masks. METHODS: A 48-minute steam sterilization process of single-use FFP2/KN95 face masks with a 15 minute holding time at 121°C was developed, validated and implemented in the Central Sterilization Departments (CSSD) of 19 different hospitals. Masks sterilized by steam and H2O2 plasma as well as new, imported masks were tested for particle filtration efficiency (PFE) and pressure drop in a custom-made test setup. RESULTS: The results of 84 masks tested on the PFE dry particle test setup showed differences of 2.3±2% (mean±SD). Test data showed that the mean PFE values of 444 sterilized FFP2 face masks from the 19 CSSDs were 90±11% (mean±SD), and those of 474 new, imported KN95/FFP2 face masks were 83±16% (mean±SD). Differences in PFE of masks received from different sterilization departments were found. CONCLUSION: Face masks can be reprocessed with 121 °C steam or H2O2 plasma sterilization with a minimal reduction in PFE. PFE comparison between filter material of sterilized masks and new, imported masks indicates that the filter material of most reprocessed masks of high quality brands can outperform new, imported face masks of unknown brands. Although the PFE of tested face masks from different sterilization departments remained efficient, using different types of sterilization equipment, can result in different PFE outcomes.

A survey to quantify wet loads after steam sterilization processes in healthcare facilities.

Wet loads after steam sterilization of medical devices in healthcare facilities are unacceptable. However, little is known about their frequency in daily practice. An online survey was distributed via four national sterilization associations, in Australia (Sterilising Research Advisory Council of Australia (Vic), Inc. (VIC SRACA)), Belgium (Vereniging sterilisatie in het ziekenhuis (VSZ)), Italy (Associazione Italiana Operatori Sanitari addetti alla Sterilizzazione - Società Scientifica (AIOS)), and The Netherlands (Vereniging van Deskundigen Steriele Medische Hulpmiddelen (VDSMH)). Seventy-eight percent of 125 hospital sterilization facilities recognized wet loads, occurring at frequencies ranging from monthly to every load. Usually, wet loads were identified by the presence of water droplets; these loads were repacked and resterilized. Given the pervasiveness of wet loads, and their impact on reprocessing times and costs, strategies to reduce their frequency are needed.