Abstract
A quantitative physical model has been expressed in terms of features generic to electrical ageing. This has been used to simulate the evolution of damage structures during the electrical ageing of insulating polymers. During the main part of the ageing process isolated regions of damage were produced at a few extremely susceptible sites. However, failure occurred via an accelerating filamentary damage path initiated in a region where a high energy concentration caused a number of adjoining sites to fail around the same time rather than through the connection of pre-existing damage regions.