Non-destructive testing (NDT) has evolved into a cornerstone of quality assurance, maintenance, and compliance across virtually every high-value industry—from aerospace and automotive to energy, construction, and process manufacturing. The ability to detect flaws, leaks, or signs of degradation without compromising the material or component being tested is not only cost-effective but often critical to safety and regulatory compliance.
Printed circuit board (PCB) inside sensitive medical equipment – image taken with a Fluke DS703 Diagnostic Video Borescope.
Modern NDT combines traditional principles with advanced technologies that bring new levels of precision, speed, and documentation to the process. Among the most versatile of these tools are ultrasound-based acoustic imagers, thermal imaging cameras, and video borescopes. This application note explores how devices such as the Fluke SB140 Sound Beacon, ii905 and ii915 Acoustic Imagers, TiS75+ Thermal Imager, and DS703 FC Video Borescope form a powerful ecosystem of NDT solutions that meet global standards and operational needs.
The Role of Non-Destructive Testing in Critical Industries
NDT is essential for detecting flaws and performance issues before failure occurs. It is widely used to identify:
- Air or fluid leaks
- Structural cracks or deformations
- Weld seam weaknesses
- Electrical hot spots
- Insulation breaches
- Corrosion or contamination inside enclosed systems
The rise in performance-based standards, digital documentation requirements, and remote inspections has accelerated demand for portable, intelligent, and multi-modal NDT tools that can deliver fast and defensible results across geographies.
Key Global NDT Standards and Compliance Frameworks
The equipment and methodologies described in this note align with international standards such as:
| Standard / Organization | Application Area |
|---|---|
| ISO 9712 / ISO 17640 | Qualification for ultrasonic testing personnel |
| ASTM E1002 / E1135 / E1316 | Acoustic and ultrasonic NDT |
| ISO 10878 | Thermography in industrial inspection |
| EN ISO 3452 | General requirements for visual inspection |
| ASME Section V (BPVC) | NDT methods in boiler and pressure vessel code |
| API 579 / 653 / 510 | Pressure vessel and tank integrity |
| IEC 60079 / ATEX | Equipment for explosive environments |
All tools covered in this note are designed for compatibility with one or more of these compliance categories, supporting their use in regulated and high-stakes environments.
Ultrasound-Based Leak Detection with the Fluke SB140 and ii905/ii915
The Fluke SB140 Sound Beacon is a compact, rugged ultrasonic emitter that generates a steady 40 kHz signal designed for use in leak and tightness testing. The frequency is suitable for airborne transmission with relatively low attenuation, making it ideal for detecting:
- Air leaks around seals, gaskets, and welds
- Compartment integrity in vehicles and enclosures
- Pressure boundary leaks without requiring actual pressurization
Used in tandem with either the Fluke ii905 or ii915 Acoustic Imager, this combination enables real-time visual detection of escaping ultrasound. The imager highlights leak sources as a dynamic sound map overlay, providing both location and relative intensity.
NDT Use Cases:
- Inspecting sealed battery enclosures, tanks, and compartments
- Localizing weld bead leaks in HVAC systems or structural panels
- Verifying cleanroom or isolation chamber integrity (ISO 14644 compliance)
- Leak testing cargo containers and watertight hatches (per ISO 1496-1 / IACS UR S31)
The ii915 offers advanced resolution and sensitivity for precision work or low-signal environments, while the ii905 is ideal for routine maintenance and production-line testing.
Thermal Imaging for Surface and Subsurface Diagnostics
Fluke's line of thermal imagers is a cornerstone of modern NDT practices. The Fluke TiS75+ Thermal Imager is particularly well-suited for industrial and field environments, offering:
- 320x240 resolution
- -20°C to 550°C (-4°F to 1022°F) temperature range
- Manual focus
- Fluke Connect compatibility for real-time data sharing and logging
NDT Applications:
- Locating overheating electrical components, loose connections, or phase imbalance
- Identifying insulation faults, thermal bridging, or heat loss
- Spotting delaminations in composites or moisture ingress
- Validating weld cooling or process uniformity in manufacturing
The TiS75+ meets inspection requirements outlined in ISO 10878, ASTM E1934, and supports compliance with energy efficiency certifications like ASHRAE 90.1 and EN ISO 12667.
For applications requiring broader temperature ranges, higher resolution and application specific features s, the Fluke Ti480 PRO may be used in place of the TiS75+.
Internal Visual Inspection with the Fluke DS703 FC Video Borescope
The Fluke DS703 FC is a rugged, high-resolution, diagnostic, video borescope designed for industrial-grade inspection of internal or hard-to-access spaces.
Features:
- 7" color touchscreen
- 720p video capture
- Dual-view scope (0° and 90°) for flexible navigation
- Fluke Connect integration for remote viewing and documentation
NDT Use Cases:
- Inspecting the internal condition of piping systems, engine chambers, or turbines
- Validating weld seams inside tanks or vessels (API 653 / ASME V)
- Checking for corrosion, cracks, or blockage in confined spaces
- Supporting preventive maintenance in oil & gas, aviation, and process manufacturing
The DS703 FC supports EN ISO 3452 for visual inspection
Combined Testing Scenarios: Multi-Tool Workflow in Practice
In the field, these tools are frequently used in combination to create a comprehensive diagnostic profile of the component or system under test:
Example: Aircraft Fuel Tank Compartment Inspection
- Use the SB140 + ii915 to locate any ultrasonic leaks in the sealed compartment.
- Apply the TiS75+ to identify hot spots or insulation weaknesses in surrounding structures.
- Deploy the DS703 FC borescope inside inspection ports to confirm visual condition and locate hidden corrosion or internal damage.
This layered methodology improves fault detection rates, speeds up decision-making, and provides a complete record trail for audits and future analysis.
Summary of Tools and Their NDT Benefits
| Tool | NDT Role | Key Advantages |
|---|---|---|
| Fluke SB140 | Ultrasound source | Portable, simple, non-pressurized tests |
| Fluke ii905 / ii915 | Acoustic imaging (leak & mech.) | Fast, visual, field-ready diagnostics |
| Fluke TiS75+ | Thermography | Surface/subsurface fault detection |
| Fluke DS703 FC | Internal visual inspection | High-res imaging in confined spaces |
Conclusion
The evolving demands of non-destructive testing require technologies that are accurate, efficient, and verifiable across a variety of industries and compliance landscapes. The combination of Fluke’s SB140, ii905/ii915, TiS75+, and DS703 FC enables multi-modal inspections that address a broad spectrum of NDT requirements while meeting key international standards.
From leak detection in sealed systems to identifying thermal anomalies and inspecting internal structures, these tools empower NDT professionals to ensure asset integrity, reduce downtime, and provide clear, documented results for audits and clients.
As NDT practices continue to modernize and diversify, investing in scalable, field-capable tools like these supports not only operational excellence but long-term regulatory and safety assurance across global operations.
About the Author
Justin Sheard is an accomplished product development leader specializing in thermal and acoustic imaging technology, particularly in preventive maintenance applications. With multiple patents and published works, Justin is a thought leader in the industry. He is dedicated to shaping the future of preventive maintenance through innovative imaging solutions that help maintenance professionals prevent unplanned downtime and improve operational efficiency. Connect with Justin on LinkedIn.