Abstract: The experiments were carried out in a confined space of 6 m×6 m×4 m to investigate the effect of high pressure water mist containing surfactant additives on cooking oil pool fires by analysing the oil temperature, flame temperature and surfactant related properties. Through the experiment, it can be found that the water mist containing the surfactant has a good effect on cooling the cooking oil and suppressing the flame, mainly related to the surface tension and foaming properties of the additives. Containing surfactant water mist on oil temperature cooling effect from high to low: 1% CAB-35 water mist > 0.01% 1-heptanol water mist > 0.01% FS-51 water mist > pure water; flame inhibition effect in turn: 1% CAB-35 water mist >0.01% FS-51 water mist > 0.01% 1-heptanol water mist > pure water. Therefore, surfactants with moderate surface tension and high foaming properties should be considered as additives for the cooling of cooking oil temperatures, while surfactants with lower surface tension and higher foaming properties should be considered as additives for the suppression of flames.

Key words: water mist, cooking oil, surfactant additive, surface tension, foam, cooling effect, suppression effect