Abstract: A diaphragm compressor having a compressor head with a hydraulic fluid plate having a fluid plate contact plane and a process fluid plate having a process plate contact plane, the plates forming a compression chamber when contact therebetween is established, the compression chamber being divided in an upper chamber and a lower chamber by a multi-layered diaphragm where a controller is configured for controlling an alternating movement of the multi-layered diaphragm towards the upper and the lower chambers respectively, a process fluid plate seal is positioned in a process fluid seal groove provided in the contact plane, the process fluid plate seal forms a process fluid seal between an upper side of the multi-layered diaphragm and the contact plane, and the process fluid plate includes a process fluid leak groove system fluidly connected to a process fluid plate leakage passage provided in the process fluid plate.