a gas monitoring apparatus with a heatable hose assembly having a central polymer tube of polyether ether ketone wrapped with a layer of polymer tape is described which is used to provide hot gases to a gas monitoring device . heating elements for heating the central polymer tube can be arranged on the layer of polymer tape as can be an element for monitoring and controlling the element for heating the central polymer tube . surrounding the arrangement can be a layer of thermal insulation and a protective jacket . the assembly is of utility for use in systems for the monitoring of acid gases from emission stacks .