A centrifugal pump (20) for use with a portable fluid collection apparatus for collecting fluid produced by a person the centrifugal pump comprising a substantially cylindrical pump chamber (26) having an inner diameter (D3) a fluid inlet (24) in fluid communication with said pump chamber and a fluid outlet (28) in fluid communication with said pump chamber. The pump further comprises an impeller (10) having an outer diameter (D2) and being rotatably mounted on a driveshaft (22) within said pump chamber intermediate said fluid inlet and said fluid outlet where said driveshaft is rotatable by driving means to rotate said impeller in use and accelerate fluid flowing into said pump chamber through said fluid inlet and out of said fluid outlet. The inner diameter of the pump chamber is substantially equal to or greater than 1.40 times the outer diameter of the impeller.
