The traditional methods of fighting metal fires are not always safe for firefighters. The sand and salts that are thrown onto the fire to suffocate the flames can lead to splashes of molten metal, putting the firefighters and the surroundings at risk. A novel process is described where magnesium fires are brought under control using a simple two-step process. First, coated cellulose flakes, which contain approx. 30% inorganic salts, are blown onto the fire from a distance of several meters. Due to its low bulk density, the material settles smoothly on the fire and immediately covers the flames for several seconds. Before the hot metal can break through this cover, a fine water spray is applied to the fire. The water spray wets the top layer of the cellulose flakes, which will begin to char from the bottom. The water evaporates from within the cellulose flake layer and withdraws heat. It was observed that no hydrogen is formed and that this technique can safely control fires. It is judged that 90 kg of flakes could safely bring a pile of 75 kg of burning Mg flakes under control. By using a pneumatic conveying unit for the flakes, firefighters can effectively and efficiently cover the flames from a safe distance. This novel method could be recommended to firefighters in industrial magnesium processing plants, as well as local firefighters in the vicinity of such plants.

A novel technique was developed to fight magnesium fires of different sizes and vigour. In essence, cellulose flakes, as they are used as blow-in insulation material, are modified with inorganic salts. The salts constitute 30 wt% of the mix and are intimately mixed into the flakes. Sodium borate and magnesium sulfate were found to be particularly effective. These salt-laden flakes are transported to a burning magnesium spot by an optimized blow-in machine (dilute phase conveying). From a distance of between 3 and 10 m, the flakes are directed at the magnesium fire. What seems to be counterintuitive works effectively and efficiently: The flakes take a few seconds to completely cover the entire metal fire. Then, the fire ceases for a short period of time, due to oxygen deficiency under the "blanket". It is at that point in time that a water mist can be directed at the covered, burning metal heap. The water will soak the upper flakes and then, heated by the lower-lying metal, start evaporating, while the fire is deprived of oxygen and is made to cool down. The water mist attack can be carried out for an extended period of time. The mixture with 15% of sodium borate was found to work best, by yielding the most stable crust. The novel process allows to control a medium to large-scale magnesium fire within less than one minute, with substantially lower danger potential for fire fighters than in current practice.