Jacket 03 : A sleeve around a cylinder or vessel arranged so that steam, water, air, refrigerants or other fluids can be circulated between them to heat or cool the contents of the vessel
Ministry of Business, Innovation and Employment, Glossary of terms and acronyms, Wellington, New Zealand 2010. http://wwwsosh.govt.nz/resources/glossary-u.shtml, (Occupn Hlth and Sfty - Brit) {530}