Decontamination assays of a laboratory with IBL Specifik's technology, ran out by Thales
The tests Thales ran out in 2007 were about the study of a lab zone decontamination and about the evaluation of the decontamination procedure in a high contaminated environment.
The tests were ran out through the "CYCLONE" decontamination system with the use of 18% of hydrogen peroxyde, 0.7% of acetic acid and 1.5% of peracetic acid. This former prototype machine, designed by IBL, is now patented and sprays high pressured (7 bars) dry steam. The disinfecting agent is injected at the boiler output, so that it can be sprayed through steam.
Tests have confirmed that the disinfectant was homogeneously spread and that the disinfection procedure through steam was very efficient : 6 log reduction after the decontamination cycle was optimized (tests ran out on Bacillus stearothermophilus).
Those tests have contributed to the improvement of the prototype thanks to relevant observations during the assays conclusions, which pointed out that the "CYCLONE" system was a promising solution because of its measured effectiveness in decontamination procedures and its compacted size.
IBL Specifik took into consideration Thales's comments and improved its prototype. Today, it has obtained reliable machines (such as VAPBIO and STAMBIO) which can spray a disinfecting solution based on hydrogen peroxyde, with much lower concentrations than the tested ones, and which have shown the same level of satisfying results (complying with the NF T 72-281 standard).
Conclusions and prospects of the assays
Conclusion on the lab decontamination
We have proved an optimum efficiency of the "CYCLONE" system with 18% of H2O2 and 1.5% of paracetic acid in the following conditions: 4min of gassing followed by 20min of contact time. The "CYCLONE" system enables an homogeneous spread of the hydrogen peroxyde steam in the whole tested zone. Nevertheless, it requires the intervention of an operator in the lab zone before the decontamination is launched, in order to protect delicate elements, in particular opticals.
Conclusion on the «CYCLONE» system
The use of the tested decontamination machine has clearly proven the efficiency of spraying hydrogen peroxyde, with at least a 6 log reduction on bacteria (spored forms) in optimized conditions. Neither spraying or contact times exceed 15 min. The longest time is the ventilation one which lowers the H2O2 concentration under 1ppm before the room is re-opened and which determines the total decontamination duration.
Thales's assays brought to light a large number of improvements which could fully develop the machine, particularly concerning the spraying nozzles and the disinfectant concentrations control. Besides those easy modifications, some deeper tests on disinfectants'concentrations were still necessary.
Thus, the conclusions of those assays were that the "CYCLON" system which sprays hydrogen peroxyde was an encouraging solution according to the measured decontamination efficiency and the compact size of the machine.
Relying on these conclusions, IBL Specifik has managed to use Thales's observations to its best advantage and improved its (now patented) prototype in order to obtain nowadays reliable machines (such as STAMBIO), which can spray a lower concentrated disinfecting solution (<8% of H2O2 and <0,2% of peracetic acid) but have shown the same level of satisfying results.