Rock salt works by lowering the freezing point of water, helping to melt snow and ice on driveways, roads, and pathways. When spread over icy surfaces, it dissolves into a brine solution that prevents further freezing, making surfaces safer and easier to walk or drive on.

Rock salt is most effective at temperatures down to around -6°C, though it may become less efficient in extreme cold. For best results, it should be applied before snowfall or frost begins, creating a barrier that stops ice bonding to the surface. Reapplying after clearing snow helps maintain safe, slip-free conditions throughout the winter.