Abstract: A method and apparatus are disclosed for determining fluid flow in a flow path of a vortex amplifier. The method comprises the steps of preventing flow of control fluid in a direction substantially opposite to a primary direction of purge fluid flow in a purge flow path of a vortex amplifier.

Abstract: A containment, such as a glovebox (4), has an air extract system comprising suction means which extracts air from the containment through a vortex amplifier (1) mounted in a containment wall opening (2). The amplifier (1) serves to control the extent of suction extracted from the containment. Air exiting from the amplifier is drawn through a filter (32) removably arranged within a filter tube (31), which extends substantially parallel to the containment wall (3). A transfer passage (29), having a cross-sectional area less than that of the wall opening (2), provides a communication between an outlet side of the amplifier (1) and the filter tube (31). At least an initial portion of the transfer passage (29) extends perpendicularly to the wall. The filter tube (31) has open ends normally closed by covers (40, 41). Removal of the covers (40, 41) enables a clean filter to be installed in the filter tube while ejecting the used filter.

Abstract: A containment, such as a glovebox (3), includes an extract system comprising an extract suction means, a filter housing (4), and a vortex amplifier (1) controlling the extent of suction by the suction means from the containment, wherein the vortex amplifier is removably mounted in an opening in a wall (2) of the containment, and the filter housing is mounted relative to the containment in such a manner that a filter (22) within the housing can be posted through an opening into the containment.The vortex amplifier is removable for cleaning.The filter housing may be mounted on the exterior of the containment in-line with the opening in which the vortex amplifier is mounted whereby the filter can be posted through the opening in which the vortex amplifier is mounted upon removal of the vortex amplifier.

Abstract: A filter module (11) comprises a housing divided internally by a partition (14) into two compartments (15, 16). At least one hollow cylindrical filter element (12) is housed in one of the compartments, the or each filter element fitting about an opening (19) in the partition (14). A filter assembly (10) comprises a plurality of filter modules (11) mounted in a fluid flow line (13) such that incoming fluid enters one of the compartments, flows through the walls of the filter elements and filtered flow emerges from the other compartment.