Final Report on the Clean Fog Test for HVAC Insulators

The results of a program of tests carried out in a number of laboratories on artificially contaminated insulators using the clean fog method are reported and analyzed. The effects of fog generation characteristics, insulator coating variability, and calculation method are considered. The analysis shows that a high level of reproducibility can be achieved. Requirements are given for ensuring that the reproducibility and repeatability of the method are adequate for its acceptance as a standard testing procedure.