A flow suppression device adapted to be connected to a high pressure fluid system includes an outer flow containment member of a porous and flexible construction. The outer flow containment member has an upstream end and a downstream end opposite the upstream end. The upstream end includes an inlet opening adapted to receive a flow stream of pressurized fluid from the high pressure fluid system and the downstream end being substantially closed. The flow suppression device also includes a primary inner flow containment member of a porous and flexible construction contained within the outer flow containment member. The primary inner flow containment member has an upstream end with an inlet opening adjacent the inlet opening of the outer flow containment member and a downstream end opposite the upstream end of the primary inner flow containment member.

The present invention provides a depth filter which contains fine particles and coarse particles, and which exhibits excellent filtration precision with respect to a high concentration fluid and/or a high viscosity fluid. This depth filter enables filtration for a long period of time, while maintaining a low filtration pressure.

The present invention is a depth filter which is obtained by winding a fiber sheet into a cylinder, and which comprises a pre-filtration layer and a microfiltration layer; the pre-filtration layer and the microfiltration layer are formed of a fiber sheet; the fiber sheet is composed of a nonwoven fabric or a web; the average fiber diameter of the fiber sheet continuously decreases from the pre-filtration layer toward the microfiltration layer; and the average weight per square meter of the fiber sheet continuously decreases from the pre-filtration layer toward the microfiltration layer.