deicer

A deicer is a substance or system used to remove ice and frozen precipitation from surfaces or to prevent its formation. Deicing aims to restore traction and safe operation by melting ice, displacing snow, or shedding frozen layers. Deicers can be chemical liquids or solids, or mechanical/thermal systems such as heated water or scrapers.

Common uses include road and airport operations, as well as maintenance for ships, aircraft, and buildings. On roads, chloride salts such as sodium chloride (rock salt), calcium chloride, and magnesium chloride are widely used, often in brine form or with anti-corrosion additives. Organic deicers such as calcium magnesium acetate and potassium acetate are used where environmental concerns or corrosion are priorities. Urea-based products are employed in certain applications. In aviation, glycol-based fluids are widely used to remove ice and pre-treat surfaces; ethylene glycol is effective but toxic, so propylene glycol is commonly preferred for environmental and safety reasons.

In aviation, deicing refers to removing ice from aircraft surfaces prior to takeoff. A related practice is anti-icing, which uses more viscous fluids to prevent further ice formation for a limited period known as holdover time. Deicing fluids are typically low-viscosity Type I; anti-icing fluids are higher-viscosity Types II, III, and IV designed for longer holdover times. Holdover time depends on temperature, rate of precipitation, and surface contamination, and must be observed to ensure clear, ice-free surfaces at departure.

Environmental and safety considerations include the potential for corrosion of metals and concrete, and the contamination of waterways from runoff. Salt-based deicers can contribute to soil and water salinity, while organic and less toxic formulations seek to mitigate such impacts. Proper handling, application, and disposal are important components of deicing programs.