This document specifies requirements and test methods for flue gas silencers made of metal that are used as accessories in order to reduce the noise level of combustion appliances.

The document covers silencers in the connecting flue pipes and on top of chimneys.

This document does not cover silencers installed as chimney sections. This document excludes active silencers.

Components tested together with the liner or system chimney are not covered by this document.