Post Indicator Valve (PIV) 2 : A post-type valve that provides a visual means of indicating "open" or "shut" position. It is found on the supply main of installed fire protection systems
Tatyana Davletshina, Industrial Fire Safety Guidebook, Noyes Publications, New Jersey 07675, USA 1998. http://www.aura-o.aura-astronomy.org/aura/sites/de fault/files/files/Referencia_Bibliografica/industr ial%20fire%20protection%20handbook.pdf, (IndFrS - Amer) {470}