A fluid filter is adapted for operatively mounting within a circuit of moving fluid in a machine. The fluid filter comprises a filter housing, and defines a fluid inlet, a fluid outlet, and a filtration medium disposed within the filter housing between the fluid inlet and the fluid outlet. A temporary closure is designed for attachment at the fluid outlet of the fluid filter after the fluid filter is used and removed from the machine. The temporary closure functions to substantially contain residual fluid within the filter housing prior to subsequent processing of the used fluid filter.