Tritium Exposure and Decontamination: The TED Facility

Ozone was used at the Tritium Laboratory Karlsruhe (TLK) for the first time for the decontamination of parts of the KATRIN experiment. The observed high decontamination efficiency led to the question of how to use ozone as an efficient cleaning tool for other facilities operated at TLK for years with tritium. To answer this question, we built the Tritium Exposure and Decontamination (TED) facility, where standard decontamination measures (purging, bake-out) can be quantitatively compared to the ozone method. To quantify the amount of ozone, and hence, the decontamination efficiency, we developed tritiumcompatible in-line ozone sensors, which are presented alongside the TED facility and first results. A first series of tritium exposure at substantial tritium amounts (≈28 bar·h) and decontamination campaigns was performed using industrial-grade stainless steel, copper, and aluminum as sample materials, and applying ozone and conventional decontamination strategies. The first results have indicated that ozone as a cleaning agent alone is not sufficient for tritium removal, and if possible, a bake-out is the most effective and least waste gas intense method. The ultimate goal of the TED facility is the development of a “plug-in” ozone generator suited for deployment in various facilities to achieve, e.g. the reduction of residual tritium in analytical systems or as a fast-acting cleaning tool prior to opening contaminated vacuum systems for modification and/or dismantling.