Inspection of timber is carried out by experienced staff using visual and hammer testing Ultrasonic testing with PURL (Portable Ultrasonic Rot Locator) and confirmation drill testing are subsequently carried out. Radio graphic testing of splices can be carried out provided safety of public is ensured.
The PURL testing is carried out at points where fungal attack is most likely. Drill testing has been traditionally used to test members. However, this is both time consuming and destructive in critical areas. Drilling is carried out only where the presence of fungal decay or termite attack has been identified.
The one area where Ultrasonic and hammer testing is unsatisfactory is the zone between cover/splice plates and joints. These are particularly critical areas because of the property for fungl to enter the timber through the end grain, the notching effect on the timber and further damage to timber caused by corrosion of plates. Ultrasonic testing is unsuitable for identifying decay at places where the steel plates, bolts, etc. are present, while continued drill testing will weaken the timber.
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