Ostomy appliance

An ostomy appliance comprising:

• at least one appliance wall of flexible sheet material forming a cavity for containing a stomal output comprising stomal gas and stomal liquid and/or solids, the at least one appliance wall comprising a stomal inlet for receiving the stomal output and a gas vent for allowing the stomal gas to migrate out of the cavity;
• and
• a filter arrangement mounted to the at least one appliance wall and comprising:
• at least one filter channel extending from at least one filter channel inlet to a filter channel outlet, wherein the at least one filter channel inlet is located in the cavity for receiving the stomal output from the cavity and the filter channel outlet is mounted in communication with the gas vent for allowing stomal gas to migrate out of the at least one filter channel to the gas vent;
• and
• at least one separation element extending at least partially along the at least one filter channel for maintaining the at least one filter channel in an open configuration along at least part of the at least one filter channel for allowing stomal gas to pass therethough;
• wherein the filter arrangement comprises filter walls overlying one another to form the at least one filter channel, channel sections being formed between the filter walls, wherein the channel sections are fluidly connected by at least one aperture through the filter walls;
• wherein the filter arrangement comprises a first channel section formed between a first filter wall and a second filter wall and extending from the at least one filter channel inlet to a first aperture in the second filter wall, and a second channel section formed between the second filter wall and a third filter wall and extending from the first aperture to a second aperture in the third filter wall.