An experimental study of the interaction of a fine water spray with liquid pool fires was performed. Spatially resolved droplet size, velocity distributions, and volume flux of the fine water spray have been obtained in two types of pressure-atomized fine spray, using LDAIAPV technology. A method to correct for the presence of droplets is presented and used to determine the heat release rate using a cone calorimeter system, the effects of water spray application on the heat release rate for liquid pool fires were studied. It was found that the volume flux of the water spray is an important factor to determine the liquid pool fire behavior. For the current experimental conditions, the flame was enlarged when lower volume flux of water is used, and suppressed significantly when larger volumes of water are used. Two opposing mechanisms compete when water sprays are applied, which is more complex than the halon agents, such as 1301. The combustion enhancement becomes insignificant when water sprays with the proper characteristics such as adequate volume flux are applied to the diffusion flame in a confined space. An experimental study of the interaction of a fine water spray with liquid pool fires was performed. Spatially resolved droplet size, velocity distributions, and volume flux of the fine water spray have been obtained in two types of pressure-atomized fine spray, using LDAIAPV technology . A method to correct for the presence of droplets is presented and used to determine the heat release rate using a cone calorimeter system, the effects of water spray application on the heat release rate for liquid pool fires were studied. It was found that the volume flux of the water spray is an important factor to determine the liquid pool fire behavior. of the current experimental conditions, the flame was enlarged when lower volume flux of water is used, and suppressed significantly when larger volumes of water are used. Two opposing mechanisms compete when water sprays are applied, which is more complex than the halon agents, such as 1301. The combustion enhancement becomes insignificant when water sprays with the proper characteristics such as adequate volume flux are applied to the diffusion flame in a confined space.