EFFECTIVENESS OF WATER-RETAINING POLYMER AS FIRE RETARDANT IN INDIRECT USE

ABSTRACT The use of fire retardants increases efficiency in fighting forest fires, however, it still presents uncertainties regarding environmental contamination, recommendations for preparation, and it lack of regulation in Brazil. In this scenario, alternative products such as water-retaining polymers, that can reduce the rapid evaporation of water, can also have positive effects in terms of reducing fire behavior. Efficiency and ways of using the water-retaining polymer as a short-duration fire retardant (indirect combat) in controlled burns in eucalyptus plantations were evaluated. Five concentrations (dilution in water), three volumes of spray solution, and two post-application times on the combustible material available in the area were evaluated. Controlled burns were conducted downwind, between 10 am and 2 pm, during dry season in the region, with micrometeorological and fire behavior assessments (fire propagation speed and length of flames). Increased spray volume and concentration of water-retaining polymer led to reductions in the spread of fire. In eucalyptus combustible material, the water-retaining polymer can be used as a fire retardant of short duration (effective up to two hours after application), considering a spray volume of 2.0 L m-2 and concentration of 0.0060% (diluted in water).