A urine handling system capsule (105) for releasing an oil mixture in the lumen of a urine handling system, the capsule (105) comprising a capsule wall defining a space filled with an oil mixture, wherein the oil mixture comprises 90-100% of an oil selected from the group consisting of silicone fluids and mineral oils or a mixture thereof, and having a viscosity of at most 600 cSt, and wherein the capsule wall is made of a water-soluble material. A urine measurement system (101) comprising an oil mixture arranged in the luminal space of the measurement system. A method for inhibiting impairment of functionality and measurement accuracy in a urine measurement system comprising applying an oil mixture to the inner surfaces of the urine measurement system. Use of an oil mixture in treatment of luminal surfaces of a urine handling system.
