An Experimental Study on the Disintegration of Extinguisher Stream

Abstract

To determine the safe distances in operating hand extinguishers against electrical equipments or live lines, the disintegration characteristics of solid stream from extinguisher nozzles were investigated by high speed flash photography and also by measuring electric current passing through the streams directed on a metal plate at 1,500 V D.C..
The conclusion is as follows : (1) The higher the discharge pressure (or discharge velocity) the longer the range beyond which the solid stream breaks up into droplets.
(2) The pressure being equal, the stream from large nozzle with smooth convergence will preserve continuity for greater distance.
(3) When pump tank extinguisher, equipped with 4mm good nozzle is operated strongly, the discharge stream momentarily preserved continuity and carry current for as far as 1.3m.