A pressure regulator, said pressure regulator comprising a housing containing a channel arranged to communicate a fluid from a fluid inlet to a fluid outlet, said channel comprising a valve seat housing, a valve seat and closure member with said closure member operable with the valve seat and valve seat housing to control flow through the channel; wherein the housing comprises a resilient diaphragm in fluid communication with the fluid and in physical communication with the closure member such that the diaphragm is operable to deform in response to a change in pressure of the fluid and such that deformation of the diaphragm causes the closure member to change position, and; wherein the section of the diaphragm not in fluid communication with the channel, is in fluid communication with the exterior of the regulator via a vent aperture and; wherein the closure member comprises an upstream valve element and downstream valve element, wherein the downstream valve element is a ridge operable with an aperture in the valve seat housing to at least partially control fluid flow, wherein said ridge of the closure member is partially or fully inside said aperture in the valve seat housing when the upstream valve element of the closure member is at or between the fully open position and a predetermined partially open position with the valve seat, to provide a restriction to fluid flow but not to fully obstruct flow.