A method may include receiving session control protocol messages to establish a session between a workstation and a user device. Also disclosed is a suspended surge prevention element that is suspended within the valve body at an adjustable distance from the venting orifice and configured to seal the initial vent orifice in response to a velocity of the flow of air through the valve body. Optionally, the abrasive aggregate can contain a secondary cross-linking agent, or a functional filler, such as a grinding aid. The first copolymer can include one or more unsaturated carboxylic acids, one or more unsaturated carboxylic anhydrides, or a combination thereof, and one or more vinyl aromatic derived units.