Abstract
The fluctuation of the time required to extinguish a flame by means of sprays of several salt solutions was investigated.
The spray was projected vertically downwards to the fires of hexane burning in a cup 8cm in diameter.
The spray nozzle was mounted 70cm above the cup and when the discharge pressure was 3.5kg/cm2, the amount of water reached the cup was 0.027ml/sec cm2.
The measured extinction times showed relatively wide range of scattering and when many measurements were repeated under the nominally identical conditions, it was found that the frequency distribution had positively skewed shape. Considering the experimental results it was concluded that average value of several measurements of extinction times was not sufficient to express the extinguishing effectiveness of salt solutions.
The consideration of the statistical feature of the frequency distribution was necessary to understand the effect of addition of salt.
