Non Destructive Testing (NDT) is a descriptive term used for the examination of materials and components in such a way that allows materials to be examined without changing or destroying their usefulness. NDT can be used to locate and size surface and subsurface flaws and defects. NDT plays a crucial role in everyday life and is necessary to assure safety and reliability. Typical examples are found in aircraft, ships, motor vehicles, pipelines, bridges, trains, power stations, refineries, buildings and oil platforms which are all inspected using NDT methods. NDT is a Quality Assurance management tool which can give impressive results when used correctly. It requires an understanding of the various methods available, their capabilities and limitations, knowledge of the relevant standards and specifications for performing the tests. Materials, products and equipment which fail to achieve their design requirements or projected life due to undetected defects may require expensive repair or early replacement. Such defects may also be the cause of unsafe conditions or catastrophic failure, as well as loss of revenue due to unplanned plant shutdown. Non Destructive Testing can be applied to each stage of an item's construction. The materials and welds can be examined using NDT and either accepted, rejected or repaired. NDT techniques can then be used to monitor the integrity of the item or structure throughout it's design life.

NDT is typically used for the following reasons

In accordance with AS1171 inspections can be performed on all magnetic metals for surface breaking and near surface discontinuities, these can be in the form of weld defects in fabrications, production faults in castings and forgings or in-service fatigue cracks in all three. For inspection, components must be in bare metal condition and cleaned of heavy surface corrosion, dirt and other contaminants. Inspections can be performed under daylight conditions (black on white contrast) or for greater sensitivity, using fluorescent particles, in low light conditions under high intensity Ultra Violet lighting.

Common items requiring Magnetic Particle Testing (MT) include:

In accordance with AS2062 inspections can be performed on all non-porous materials for surface breaking flaws, these can be in the form of weld defects in fabrications, production faults in castings and forgings or in-service fatigue cracks in all three. PT inspection is primarily used on non-magnetic steels (300 series Stainless steels, Aluminium, Bronze, etc.) and non-metals. For inspections, components must be in bare metal condition and cleaned of heavy surface corrosion, dirt and other contaminants. Inspections can be performed under daylight conditions (red on white contrast) or for greater sensitivity, using fluorescent particles, in low light conditions under high intensity Ultra Violet lighting.

Common items requiring Dye Penetrant Testing (PT) include: