Suitability of a Resonant Sonic System for Decay Detection in Softwood Poles

A resonant sonic system has been established as satisfactory for the detection of serious internal decay for both treated and untreated hardwood (eucalyptus) poles used for electricity distribution purposes [1]. This paper summarizes the results of an investigation of the Resotest method conducted in New Zealand on a variety of softwood poles used for electricity distribution and communications purposes and concludes that the method is also valid for softwoods.