Zone Indicator 1 : A part of fire alarm indicating equipment which visually indicates the zone of origin of a fire alarm or fault warning signal. (BS 4422 (4))
H. J. Porter (Chairman - Technical Committee), Dictionary of Fire Technology, The Institution of Fire Engineers, The Victory Press (Leicester) Ltd. 1979 UK. (Fr Tech - Brit) {81}
Solutions Fire Safety Ltd, Fire Safety Glossary: An A - Z of definitions regarding fire safety terms and vocabulary, Solutions Fire Safety Ltd, UK 2012. http://solutionsfire.co.uk/Fire-literatures-PDF/Fi re-Safety-Glossary.pdf, (Fr Sfty - Brit) {465}