Abstract: The invention relates to an electrochemical gas sensing apparatus for sensing one or more analytes, such as NO2 and/or O3, in a sample gas and a method of using same. The apparatus uses Mn2O3 as a filter for ozone. The Mn2O3 may take the form of a powder which may be unmixed, mixed with various PTFE particles sizes, formed into a solid layer deposited onto a membrane and/or pretreated with NO2.

Abstract: The invention relates to an electrochemical gas sensing apparatus for sensing one or more analytes, such as NO2 and/or O3, in a sample gas and a method of using same. The apparatus uses Mn2O3 as a filter for ozone. The Mn2O3 may take the form of a powder which may be unmixed, mixed with various PTFE particles sizes, formed into a solid layer deposited onto a membrane and/or pretreated with NO2.

Abstract: The invention relates to an amperometric electrochemical gas sensing apparatus for sensing NO2 and O3 in a sample gas and a method of using same. The apparatus comprises: a first working electrode which is a carbon electrode and at which both NO2 and O3 are reducible to thereby generate a current; a second working electrode which is a carbon electrode and at which NO2 is reducible to thereby generate a current; and an O3 filter material comprising 1-20% MnO2 by weight mixed with binder and adjacent the second working electrode, and said apparatus is configured such that, in operation, the first working electrode and the O3 filter are exposed to the sample gas in parallel.