The approach to hail suppression varies considerably depending on the conceptual model considered to be most closely related to the storms in the region of interest . The differences between conceptual storm models result from different environmental conditions and different perceptions of storm structure . Perceptions of storm structure , in turn , vary from scientist to scientist and depend on the stormobserving systems and numerical models available for research .

The hail control technique in Romania is based on the conceptual model according to which hailstones grow from embryos originating from frozen supercooled water droplets . In a region with a high level of liquid water originating from the accumulation of supercooled water droplets , a few droplets naturally freeze and grow rapidly to hailstone size in the water - rich environment . The Romanian hail control technique consists of the direct injection of silver iodide seeding material into the region with high radar reflectivity and, most likely , a large amount of supercooled water . For this , rockets are used that ensure the dispersion of the silver iodide seeding material up to more than 8 km altitude , after which they self - destruct . It is assumed that the dispersed silver iodide is then engulfed by the supercooled water droplets ( or initiates the freezing of small ice crystals that are engulfed by the supercooled water droplets ) and initiates freezing . The numerous frozen droplets then compete for their benefit for the supercooled liquid water , inhibiting the formation of crystals .