A Literature Review of the Effects of Fire Smoke on Electrical Equipment

A review is presented of the state of the art of smoke production measurement, prediction of smoke impact as part of computer-based fire modeling, and measurement and prediction of the impact of smoke through deposition of soot on and corrosion of electrical equipment. The literature review on smoke corrosivity testing and damage due to smoke deposition emphasizes (despite extensive research on smoke corrositity) the lack of validated and widely applicable prescriptive or performance based methods to assure electrical equipment survivability given exposure to fire smoke. Circuit bridging via current leakage through deposited smoke was identified as an important mechanism of electronic and electrical equipment failure during NPP fires. In the near term, assessment of potential damage can reasonably be based on the airborne smoke exposure concentration and, perhaps, the exposure duration. Hence, models that can predict the airborne smoke concentration would be sufficient to suit short-term analysis needs. In the longer term, it would be desirable to develop models that could estimate the deposition behavior of smoke, as well and specifically correlate the combination of deposited and airborne smoke to component damage.