Assessment of extinguishing waters from intermediate-scale fire tests

Abstract

Water is, for several reasons, by far the most widely used agent for extinguishing fires. Large quantities will turn to steam, but much will drain away with more or less ecotoxic effects on the ground and aquatic environments. Although this fire water run-off does not usually present a serious risk to the environment, it is reasonable to take precautions and to have quick in situ measures for predicting the likely consequences for, for example, a nearby mechanobiological, wastewater treatment plant. The enormous environmental damage caused by extinguishing waters in the past has focused attention on this environmental problem. From the detailed assessments of relevant parameters, it is demonstrated that product-related potency values may be capable of distinguishing between products. Some products tend to have toxic potencies that can be as much as almost four times higher than others. Risk assessments will not only reveal the routes by which major environmental damage might occur but also areas where fire precautions are inadequate. Special tasks must be allocated to the fire brigade: the earlier a fire can be tackled, the greater the chance of successfully extinguishing it and minimising the quantity of contaminated water. In this context, other active precautions such as fire detectors and sprinklers also help to minimise the ecotoxic effect of extinguishing waters. The primary fire-safety objective is to prevent any fires, rather than to deal with their consequences.