By Justin Sheard, Fluke Acoustic Imaging Expert
Leak and tightness testing in the maritime industry is a mission-critical process with far-reaching implications. From cargo protection to seaworthiness and environmental safety, the ability to identify and resolve leaks across containers, compartments, and vessel systems is essential. Compliance with international maritime standards requires routine, accurate, and verifiable testing to maintain safe operations and ensure goods arrive at their destination intact.
Leak detection in the maritime industry is essential to safety, cargo integrity, and regulatory compliance.
Traditional leak testing methods such as water spray, pressure differentials, or manual inspections have limitations, especially in large-scale or remote port operations. The use of ultrasound-based acoustic imaging, specifically employing the Fluke SB140 Sound Beacon and the Fluke ii905 or ii915 Acoustic Imager, offers a transformative solution. This method delivers fast, accurate, and non-invasive detection of air or water leakage—ideal for maritime environments where time, accuracy, and safety are paramount.
Leak Testing Requirements in Maritime Applications
The shipping and maritime transport sector is governed by several international conventions and regulatory bodies, including:
- International Maritime Organization (IMO)
- Safety of Life at Sea (SOLAS)
- International Convention for Safe Containers (CSC)
- IACS Unified Requirements (e.g., UR S31 for hatch cover integrity)
- ISO 1496-1: Series of standards that include leak testing protocols for containers
Testing ensures that:
- Cargo containers are free from breaches that may allow water ingress
- Reefer (refrigerated) units maintain temperature and moisture barriers
- Bulkheads, hatch covers, and fuel/oil tanks are watertight and structurally sound
- Shipboard compartments meet stability and safety requirements in accordance with SOLAS
Fluke ii905 Acoustic Imager and Fluke SB140 Sound Beacon
Ultrasound Leak Detection in Cargo Containers
Cargo containers are subject to wear from repeated loading cycles, sea spray, and environmental stressors. Even minor leaks can result in cargo damage, particularly in sensitive shipments such as electronics, pharmaceuticals, or textiles.
Testing Methods:
- Light Leak Testing: Subjective, only effective in dark conditions
- Water Spray Testing (ISO 1496-1): Simulates rain conditions but requires time and space
- Ultrasound Testing (ISO 1496-1 Annex C): Uses ultrasonic transmitters to detect seal breaches quickly and accurately
The Fluke SB140 Sound Beacon, emitting a 40 kHz signal, is placed inside a container. An operator uses the Fluke ii905 or ii915 Acoustic Imager to scan door seals, panel edges, and vents. The imager, in Beacon Mode, visually displays ultrasound escaping through any leak points, allowing for immediate corrective action.
This method is particularly effective for:
- Standard dry containers (TEU, FEU)
- Insulated or refrigerated containers
- Tank containers for liquids and hazardous materials
Leak Detection in Vessel Compartments and Systems
In addition to container inspections, ships require routine leak testing across various critical structures:
Key Areas:
- Hatch Covers: Must be watertight to protect cargo from spray and rainfall
- Ballast and Void Tanks: Leaks can compromise vessel trim and stability
- Fuel and Oil Compartments: Leakage poses fire and environmental risks
- Bulkheads and Engine Room Barriers: Integrity required to isolate critical zones
Ultrasound is used to test these areas without flooding or pressurizing the system. Instead, the SB140 Sound Beacon is placed inside a sealed compartment or tank, and the imager detects escaping ultrasonic signals from the outside.
Advantages of Ultrasound Acoustic Imaging in Maritime Operations
| Feature | Benefit |
|---|---|
| No pressurization required | Enables safe testing in operational or static environments |
| Visual leak localization | Pinpoints exact breach location with high precision |
| Fast testing cycle | Supports quick turnaround at ports or onboard during inspections |
| Non-destructive | No water, gases, or pressure applied to systems |
| Portable and durable | Suited for dockside, onboard, or field conditions |
| Documentation ready | Acoustic imager provides photo records for audits and compliance |
Use Case: Reefer Container Testing at Portside Inspection Station
A global shipping company managing thousands of refrigerated containers needed a faster method to inspect door seal integrity before vessel loading. Water testing proved messy and slow, while light leak testing was ineffective during daylight.
By placing the Fluke SB140 Sound Beacon inside the reefer unit and scanning from outside with a Fluke ii915 Acoustic Imager, inspectors identified seal gaps, insulation panel defects, and hinge misalignments in under two minutes per unit. The results were visually documented, and defective containers were flagged for repair or rerouting.
The system proved highly reliable, easy to train on, and robust enough to withstand the rigors of portside deployment in variable weather conditions.
Regulatory Alignment and Industry Standards
- ISO 1496-1 (Annex C): Specifies use of ultrasonic leak detection in container testing
- IACS UR S31: Hatch cover tightness test protocols including ultrasound methods
- IMO SOLAS: Safety and watertightness requirements for bulkhead and compartment integrity
- CSC Convention: Mandates container inspection and certification prior to transport
- ISPS Code: Supports structural security inspections for port and vessel access
Ultrasound inspection not only meets these standards but often surpasses legacy methods in both precision and efficiency.
Conclusion
Leak detection in the maritime industry is essential to safety, cargo integrity, and regulatory compliance. As global trade volumes and container throughput increase, so too does the need for fast, scalable, and accurate testing methods.
Ultrasound acoustic imaging with the Fluke SB140 Sound Beacon and Fluke ii905/ii915 imagers offers a portable, efficient, and standards-compliant solution for leak and tightness testing in containers and onboard vessel systems. By enabling real-time visual detection without the need for pressurization or water, this method supports better decision-making, faster repairs, and more reliable shipping operations.
For fleet managers, inspectors, and marine engineers, ultrasound technology delivers not only enhanced testing capabilities but also a smarter path to maintaining maritime safety and performance in an increasingly regulated industry.
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.