Non-Destructive Testing (NDT) is a crucial technique used in various industries, particularly in the commercial diving sector, to assess the integrity of materials and structures without causing damage. NDT methods are essential for ensuring the safety and reliability of underwater infrastructure, such as oil rigs, pipelines, and ship hulls. This article looks at the definition and significance of NDT, its application in commercial diving, and an overview of the professional NDT equipment supplied by iSubC.

Definition and Importance of NDT Equipment

Non-Destructive Testing (NDT) refers to a range of analysis techniques used to evaluate the properties of a material, component, or system without causing damage. NDT methods are essential for detecting and characterising defects, measuring material properties, and ensuring the structural integrity of critical components. Common NDT techniques include ultrasonic testing, magnetic particle inspection, radiography, and eddy current testing.

The importance of NDT lies in its ability to provide crucial information about the condition of structures and materials, enabling preventive maintenance and avoiding catastrophic failures. In industries such as aerospace, construction, and maritime, NDT plays a vital role in maintaining safety standards and prolonging the lifespan of assets.

Application of NDT Equipment in Commercial Diving

In the commercial diving industry, NDT equipment is indispensable for inspecting underwater structures and ensuring their continued safe operation. Divers equipped with specialised NDT tools conduct surveys and inspections on offshore platforms, subsea pipelines, ship hulls, and other underwater installations. The harsh marine environment presents unique challenges, making reliability and durability of NDT equipment essential.

Commercial divers utilise various NDT techniques to perform tasks such as:

  1. Corrosion Monitoring: Assessing the extent of corrosion on metal structures and evaluating the effectiveness of cathodic protection systems.
  2. Thickness Measurement: Measuring the remaining thickness of metal components to determine their structural integrity and remaining service life.
  3. Crack Detection: Identifying cracks and other surface or subsurface defects that could compromise the structural integrity of underwater assets.
  4. Weld Inspection: Evaluating the quality of welds on underwater structures to ensure they meet safety and performance standards.

iSubC: Suppliers of Professional NDT Equipment

At iSubC commercial diving equipment, we specialise in supplying high-quality NDT equipment tailored for the rigorous demands of commercial diving. Our product offerings are designed to provide accurate and reliable measurements in challenging underwater environments. Below is a summary of our key NDT products:

BathyCorrometer Pro Mk7 Basic Kit

Ordering Code: 6004-0128

The BathyCorrometer® Pro MK7 Basic Kit is the latest iteration of the industry-standard BathyCorrometer®, renowned for its robust construction and reliability since 1971. This device is designed to simplify the measurement of cathodic protection potentials on offshore structures. Key features include:

  • Rugged and dependable construction.
  • Enhanced reliability and accuracy.
  • Negative display of structure-to-electrolyte potential.

BathyCorrometer Pro Mk7

Complete with Calibration Kit

Ordering Code: 6004-0130

The BathyCorrometer® Pro Mk7 continues the legacy of the BathyCorrometer® series, offering advancements that make the measurement process more straightforward and reliable. This kit includes a calibration kit, ensuring that divers can maintain the accuracy of their measurements. Notable attributes include:

  • Simplified measurement process.
  • Rugged construction for harsh environments.
  • Enhanced reliability for subsea corrosion surveys.

BathyCorrometer Pro Mk7 Standard Kit

Ordering Code: 6004-0129

The BathyCorrometer® Pro V6 Standard Kit is another version of the BathyCorrometer® series, providing reliable service for subsea corrosion surveys. This kit is designed to measure cathodic protection potentials on offshore structures effectively. Key features include:

  • Industry-standard reliability.
  • Robust and dependable construction.
  • Simplified measurement process.

CYGNUS DIVE Mk2 Ultrasonic Thickness Gauge

Ordering Code: 001-7200/2

The CYGNUS DIVE Mk2 is a wrist-mountable ultrasonic thickness gauge designed for divers. It offers a hands-free operation, allowing divers to focus on their tasks while obtaining accurate thickness measurements. Key features include:

  • Robust and wrist-mountable design.
  • Large, easy-to-read display.
  • Simple operation with only two buttons.

Cygnus Underwater Mk4 Ultrasonic Thickness Gauge

Ordering Code: 001-9933/4

The Cygnus Underwater Mk4 is the original diver-held ultrasonic thickness gauge, designed for use in subsea maintenance and surveys. It remains the industry standard, offering depth ratings up to 300 meters and accurate measurements through coatings up to 20 mm thick. Key features include:

  • Depth rated to 300 meters.
  • Accurate thickness measurement through thick coatings.
  • Bright LED display for easy viewing.

Subsea MPI Equipment

Divers Subsea MPI Unit – System 12

Ordering Code: SYSTEM12

The System 12 MPI unit is a compact, battery-powered system ideal for shallow water or splash zone applications. Based on the proven System 3 unit, it offers powerful performance in a small package. Features include:

  • Portable and compact design.
  • Battery-powered operation with no umbilical connection required.
  • Diver control for UV Lamp and Magnetic Yoke.

Divers Subsea MPI Unit – System 3

Ordering Code: SYSTEM3

The System 3 is a field-proven subsea MPI unit with an impressive track record. It offers three modes of magnetization and complete control from a stainless-steel housed topside unit. Key features include:

  • Flexibility with AC or HWDC magnetization.
  • In-built safety features for operator protection.
  • Proven performance in arduous conditions.


Non-Destructive Testing (NDT) is a vital aspect of maintaining the integrity and safety of underwater structures. At iSubC, we are committed to providing high quality NDT equipment that meets the rigorous demands of commercial diving. Our products, including the BathyCorrometer series, Cygnus thickness gauges, and Subsea MPI units, are designed to deliver reliable and accurate results in challenging underwater environments. By equipping divers with the best tools available, we help ensure the continued safety and efficiency of underwater operations.

Contact iSubC today to discuss your requirements.