Non-Destructive Testing (NDT): Qualified Personnel for Inspections of Materials, Structures and Industrial Plants

Istituto Giordano provides Non-Destructive Testing (NDT) services for industrial, civil engineering, marine and naval applications.

Inspections are carried out on steel, cast iron, aluminium, brass, plexiglass and composite materials such as fiberglass and carbon fibre, allowing the integrity and technical characteristics of components to be verified without affecting their performance or compromising their usability.

Non-destructive testing is applied throughout the entire life cycle of a structure or component: during manufacturing for quality control, during pre-commissioning inspections, throughout scheduled maintenance and periodic inspections, and following failures, accidents or exceptional events. The objective is to detect defects, deterioration or anomalies at an early stage, reducing the risk of plant downtime, improving safety and optimising maintenance costs.

CND and NDT refer to exactly the same concept. CND is the Italian acronym for Controlli Non Distruttivi (or Prove Non Distruttive – PND), while NDT stands for Non-Destructive Testing, the internationally recognised term.
 

Main Non-Destructive Testing methods

Each non-destructive testing method has specific characteristics and is selected according to the material being inspected, the type of defect to be detected and the operating conditions. In many cases, several complementary techniques are combined to obtain a more comprehensive assessment of the component's integrity.

• Visual Testing (VT)

Visual Testing (VT) is the first level of inspection and is often carried out before any other testing method. It allows inspectors to identify surface defects, deformation, corrosion, wear, visible cracks, welding imperfections and geometric irregularities. Inspections may be performed with the naked eye or by using optical instruments, endoscopes, videoscopes and digital imaging systems.

• Magnetic Particle Testing (MT)

Magnetic Particle Testing (MT) is used exclusively on ferromagnetic materials. After the component has been magnetised, magnetic particles are applied to its surface, where they accumulate around surface or near-surface discontinuities, making cracks, inclusions and welding defects immediately visible. This is a fast, reliable and widely adopted technique for inspecting steel structures, pipelines and pressure vessels.

• Penetrant Testing (PT)

Penetrant Testing (PT) is used to detect surface-breaking defects, even those of very small dimensions. After the penetrant is applied and the excess product removed, a developer draws the penetrant out of any discontinuities through capillary action, making them clearly visible. This method is suitable for metallic materials as well as many non-porous materials, making it particularly effective for inspecting welds, castings, machined components and aerospace and marine parts.

• Ultrasonic Testing (UT)

Ultrasonic Testing (UT) uses high-frequency sound waves that propagate through the material. By analysing the echoes reflected by internal discontinuities, inspectors can detect internal defects, measure remaining wall thickness and assess the structural integrity of the component. This technique is particularly effective for steels, metal alloys and composite materials, providing accurate inspections even when access is available from only one side of the component.

• Radiographic Testing (RT)

Radiographic Testing (RT) uses X-rays or gamma rays to produce an image of the internal structure of a component. It is particularly suitable for detecting porosity, inclusions, lack of fusion and other volumetric defects in welds and castings. One of its main advantages is the ability to permanently document inspection results through radiographic images for future reference and comparison.

• Thermographic Testing (TT)

Thermographic Testing (TT) uses infrared cameras to detect temperature variations on the surface of materials. Thermal anomalies can reveal hidden defects such as delamination, debonding, moisture ingress, voids, bonding defects and energy losses. It is particularly effective for inspecting composite materials, buildings, electrical installations and industrial systems.
 

Non-Destructive Testing for industrial applications

Non-destructive testing is an essential tool for companies and operators who need to verify the quality of industrial plants, equipment, structures and products, both during manufacturing and throughout their service life.

Istituto Giordano provides Level II and Level III NDT inspectors as well as specialists for the preparation of inspection procedures and the execution of testing activities in accordance with ISO 9712, ASNT SNT-TC-1A and the Pressure Equipment Directive (PED) 2014/68/EU.

Personnel qualification is essential to ensure reliable inspection results. Level II operators are qualified to perform inspections, interpret test results and prepare inspection reports, while Level III personnel have advanced expertise in developing procedures, supervising inspection activities, providing technical support and managing non-destructive testing programmes.

Our technicians perform non-destructive testing of welds, verifying the presence of discontinuities or defects that could compromise safety and performance.
 

Non-Destructive Testing for civil engineering and construction

Non-destructive testing of concrete and structural elements is now widely used in civil engineering, building rehabilitation and the conservation of historic structures.

Inspections can be carried out on existing buildings, bridges, viaducts, infrastructure, reinforced concrete structures, steel structures and masonry. The results provide valuable information on the condition of the structure, identify signs of deterioration and support engineers and project managers in planning maintenance, strengthening or seismic retrofitting interventions.

Italian Technical Standards for Construction increasingly require inspections of existing structures and construction materials. For this reason, Istituto Giordano employs personnel certified in accordance with UNI EN ISO 9712 for the following methods:

• MP – Flat Jack Testing

Used to determine the stress state and certain mechanical properties of existing masonry without compromising the stability of the structure.

• PC – Load Testing

Verifies the actual behaviour of a structure under controlled loading conditions by comparing measured results with design values or structural assessment calculations.

• UT – Ultrasonic Testing

Ultrasonic inspections use high-frequency sound waves to detect internal discontinuities, welding defects and corrosion that are not visible from the surface. The technique also enables accurate thickness measurements and is widely used for inspecting steel structures, pipelines, pressure vessels and composite materials.

• MG – Magnetometric Surveys

Used to locate reinforcing bars within concrete, determine concrete cover thickness and provide essential information before coring, demolition or structural repair works.

• SC – Rebound Hammer Testing

Using a rebound hammer, this method provides an indirect estimate of the surface strength of concrete. It is frequently combined with ultrasonic testing to improve the reliability of the assessment.

• TT – Thermographic Testing

Thermographic inspections use infrared cameras to detect temperature differences across material surfaces, allowing hidden anomalies to be identified without physical contact. The technique is particularly effective for detecting delamination, debonding, moisture ingress, insulation defects and thermal bridges in buildings, industrial plants and composite materials.

• MO – Structural Health Monitoring

This method involves installing monitoring instruments capable of continuously measuring deformation, displacement, vibration and other significant parameters, providing ongoing assessment of the structural behaviour over time.
 

Non-Destructive Testing for the marine and naval industry

Non-destructive testing for the marine sector enables the detection of both surface and internal defects, assessment of structural condition and measurement of material thickness without causing damage.

NDT also plays an important role in preventive maintenance for pleasure craft, commercial vessels and ships. By assessing the actual condition of structures, inspections help optimise maintenance planning, reduce unnecessary downtime and preserve the safety, reliability and value of the vessel over time.

Inspections may be carried out for expert assessments, post-accident investigations, maintenance of classification requirements or routine condition surveys.

Istituto Giordano relies on qualified NDT operators, specialised technicians and Level III NDT personnel certified in accordance with UNI ISO 9712 and ASNT SNT-TC-1A.

Ultrasonic Testing (UT) is used to measure the thickness of hulls, decks and bulkheads and to identify internal defects and anomalies in metallic structures.

Weld inspections are among the most common NDT applications, enabling the detection of discontinuities in the structural joints of hulls and metallic components.

Penetrant Testing (PT) is used to reveal surface-breaking defects, while Thermographic Testing (TT) allows inspectors to detect delamination, moisture ingress and previous repair work on fiberglass hulls and other composite materials.