Abstract: Air filter and silencers comprise an air filter element having an annular body with openings at opposed ends. A top is attached over one of ends, has an outer flange sealed to the element, and includes a central section extending across the air filter element end. The top central section has a convex-shaped geometry with a radius of curvature projecting outwardly and away from the air filter element. The top central section includes a sound deadening material directed towards the air filter element. The top central section has a radius of curvature greater than the radius of an inside diameter of the air filter element. The air filter and silencer is used with an air filter assembly that includes a housing removably attached to the air filter and silencer, and that has an internal chamber projecting axially into the air filter and silencer with a sound deadening material disposed therein.

Abstract: A fluid monitoring apparatus and method is disclosed for use in an underground utility vault. Specifically, a system utilizing multiple sensors to determine the total amount and type of fluid present in a utility vault is disclosed. A first sensor located above the fluid detects and determines the overall depth of fluid present. A second sensor, relying on specific properties of the fluid(s) present, is located in contact with the fluids present. The information regarding specific fluid level and type is conveyed to a central location for monitoring.

Abstract: In a resilient chamber sampling apparatus incorporating a resilient body having a dished cavity area which is squeezed to pressure fluid trapped in the dished area, an improved form preferably incorporates an alternate anvil. It has a facing plate member at the end of the probe over a solid anvil. The cap or plate has a small hole in the center and telescopes with a small peripheral skirt aligning the cap with the resilient plug. On closure, high pressure is formed to force fluid from the cavity in the resilient body. When the probe is pulled away from the resilient body, the vacuum breaker slides in telescoping movement, and opens an external passage to fill the chamber where the fluid was pumped from, and the chamber is restored to its full size without pulling a vacuum, to avoid damage which might occur otherwise.