A test device for determining the particle load of pressurized hydrogen includes a housing (2), with an inlet (4) and an outlet (8) for the inflow or outflow of hydrogen, respectively. A sampling chamber (52) has a filter holder (44) for a test filter (58). A sample amount of hydrogen can flow through the test filter during a test procedure. After the test procedure has been completed, the test filter can be removed from the sampling chamber (52) for evaluating the deposition of particles. A venting device (64, 70) for reducing the pressure in the sampling chamber (52) is arranged inside the housing (2) and discharges any remaining hydrogen, at least partially, in the direction of the inlet (4) of the test device after the hydrogen has stopped flowing from the testing device.