These EO vacuum sterilisation chambers are designed for carrying out cycles with 90% or even 100% EO. These high concentrations allow to work at low pressures in the chamber. Since the construction of a vessel to work in these conditions is relatively simple (it is not rated as a pressure vessel), they offer the best capacity throughput. However these mixtures are flammable and explosive and therefore, the installation has to be ATEX compliant. STERISYS manufactures and supplies according to ATEX, DIN EN 1422, DIN EN 11135, FDA and GAMP guidelines and regulations.