(70cv) Ignitability of Spraying Liquid due to Electrostatic Spark

In this paper, we report on experimental results dealing with the minimum ignition energy (MIE) of a spraying liquid due to an electrostatic spark in various conditions. The spray gun (hand-held type) using practical coating plants and Kerosene as the liquid material were used in this study. The liquid was pneumatically conveyed to the spray gun and automatically sprayed for 3 s for the ignitability measurements. The MIE of liquid was also investigated as a function of the position in spraying material clouds. An important result was found that the spraying liquid examined was so sensitive that even a spark with a very low energy, such as several mJ, could ignite them. This result was attributed to the particle sizes and densities of spraying liquid, and so on. Experimental details are described in this paper.