Brandfarliga vätskor i syrereducerade miljöer

Sammanfattning: Unmanned warehouses are increasing in number as workers are replaced by automated robotic systems. This type of facility, among others, is well suited for an oxygen reduction system for fire protection. By lowering the oxygen concentration, the risk of fire propagation is reduced and might be hindered altogether. In order to do so the limiting oxygen concentration (LOC) for the dimensioning material in the protected area needs to be known. The available literature on flammable liquids in these conditions is limited and more knowledge is needed. The goal of this work is to examine flammable liquids to hopefully provide usable information when designing an oxygen reduction system. In this report the limiting oxygen concentration (LOC) for five common flammable liquids is presented. The heat release rate (HRR), mass loss rate (MLR) and CO/C02-yield for all liquids is analysed for three oxygen concentrations (21%, 17% and 15%). This is done by experiments using a cone calorimeter with a chamber that allows the atmosphere to be controlled by a set flow of air and nitrogen. When analysing the results, it is established that the HRR and MLR do not indicate any general pattern when the oxygen concentration is lowered. For one of the liquids there is little or no impact on the HRR at lower concentrations. When establishing the LOC with external heat it is found that a higher radiation does not equal a lower LOC.