Double membrane transducer protector

A device (10) of a protector for a transducer, comprising: a first tubular connector (20) is configured for connection to a first tube; a second tubular connector (30) which is configured for connection to a second tube; and a body (40) positioned between said first (20) and second (30) tubular connectors, wherein a first filter member (50) is positioned between said body (40) and said first tubular connector (20) , and wherein a second filter member (60) is positioned between said body (40) and said second tubular connector (30), wherein at least part of said body (40) is made of a transparent material, and wherein said body (40) further comprises a biological or chemical indicator (70).