The invention relates to apparatus for measuring medical data in pressurised chamber comprising: a computing device, the computing device comprising at least one medical data gathering module； and, a battery module for powering the computing device, the battery module comprising: at least two battery packs in parallel； each battery pack comprising at least one individual cell rated for use in a pressurised chamber, such as a hyperbaric chamber and/or saturation chamber； each battery pack further comprising at least one first resettable fuse in series with the at least one individual cell； whereby charging of one battery pack by another is substantially prevented within the battery module. The invention further relates to apparatus for computing in a pressurised chamber comprising a computing device and a battery module for powering the computing device. The apparatus further relates to a battery module for use in such apparatus and a method of measuring medical data in a pressurised chamber.
