For all devices (Astral, Stellar and Lumis), it is recommended that an antibacterial Heat Moisture Exchange Filter (HME) or antibacterial filter will be used to reduce the risk of contamination. While ResMed do supply these filters, other manufacturers can provide similar filters with the same antiviral/antibacterial properties. To prevent the risk of cross-contamination, it is essential that an antibacterial filter is placed on the inspiratory port if the device is to be used on multiple patients . Please note that the filters need to be changed frequently (for more precise information please refer to the filter user instruction) and also when the devices are used on multiple patients. In addition, patients should follow ResMed’s user guide.