Water mist systems are fire extinguishing devices installed in cargo areas, machinery areas, and passenger quarters of ships (mainly bulk carriers) according to the requirements of the International Maritime Organization. They consist of water pumps, pipes, valves, and water mist nozzles. They comply with standards such as the "General Technical Conditions for Marine Fine Water Mist Fire Extinguishing Systems" (GB/T2224/-2008). The system uses single-phase or two-phase flow media, and operating pressures are divided into low-pressure (≤1.21MPa), medium-pressure (1.21-3.45MPa), and high-pressure (≥3.5MPa) types. High-pressure fine water mist fire extinguishing systems consist of fine water mist nozzles, a water supply network, and a pressurization device.
This system achieves cooling, suffocation, and isolation fire extinguishing by spraying micron-sized water mist, and can extinguish Class A, B, and E fires. Impact nozzles are mostly used for the protection of flammable materials with a flash point below 66℃. Compared to traditional water spray systems, it reduces water consumption by more than 80% and has the ability to block heat radiation, reduce smoke toxicity, and extinguish fires involving electricity. It is not suitable for fires involving peroxides or water-reactive substances such as potassium and sodium metals.
