Smoke tests of natural esters and mineral oils under trasformer fire conditions

In the framework of the activities of the Italian Institutional Working Group on Natural Esters, smoke production under controlled fire conditions of such innovative insulating liquids has been studied in comparison with that released by traditional mineral oil, normally used in electrical power transformers. This comparison has been made in terms of solid particulates, carbon monoxide (CO), Total Organic Carbon (TOC), Polycyclic Aromatic Hydrocarbons (PAH), Volatile Organic Compounds (VOC) and Aldehydes in different conditions of greater or lower presence of atmospheric oxygen. The main results are reported in this contribution.