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Aircrafts and runways de-icing operations with anti-icing fluids are still the most commonly used methods. In the specific case of aircrafts, they do contain glycols. Nevertheless, since two decades now, major environmental concerns are raised, along with important associated costs. Furthermore, once applied either on aircrafts or on runways, these fluids are diluted because of water brought from adverse weather conditions (rain, snow, icy conditions), conducting to increasing the freezing point from a subzero level to 0°C. The characterization of the freezing points of these fluids is indeed crucial for safety reasons. For years now, Raman spectroscopy is used for the characterization of these fluids, specifically the freezing point. But the presence of dyes did perturb the usual spectroscopic characterization.

Winter maintenance is based on the intervention of operating services, as well as the use of deicers. Each year, in France, thousands of tons of deicers are spread through runways and taxiways. On the airport sector, the main deicers are sodium or potassium acetates and formates. All these deicers aim to prevent ice formation (preventive strategy) and/or improve the ice melting of snow residual film (curative strategy) at temperatures below 0°C. The operating principle of these compounds is based on the lowering of the solution's freezing point once dissolved in water. The phase diagram's knowledge is predominant to determine the deicer's amount to be applied on the surface. It provides a way to optimize their amounts applied with respect to weather conditions, present or forecasted. The Center for Technical Studies of Equipment in East of France (CETE de l'Est) developed and implemented a method based on Raman spectroscopy to characterize aqueous solutions of airport de-icers.