According to ISO 15848-1, fugitive emissions are “chemical or mixture of chemicals, in any physical form, which represents an unanticipated or spurious leak from equipment on an industrial site”. In petrochemical plants, approximately 60-70% of fugitive emissions come from valves.
Valve’s sources of leakage are: Stem and Body to bonnet joint. To minimize the fugitive emissions; special considerations shall be taken when choosing the proper packing and soft sealing to minimize the fugitive emissions, in some cases the use of bellows shall be mandatory.
Fugitive emissions testing shall be done to make sure that valves are certified according to one of the well-known fugitive emissions standards according to the designer requirements.