Sentry IMS – Integrity Monitoring Sonar
Sentry IMS – Capable of monitoring over one billion cubic feet of seawater.
Our Sentry integrity monitoring sonar system is has been developed to automatically warn of integrity breaches around subsea oil and gas assets. The system is capable of monitoring more than one billion cubic feet of seawater, with 360° of coverage from a single sonar sensor location.

Sentry at a glance
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Developed from our field proven detection, localisation and classification sonar technology
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Provides 360 degree, high volume coverage from a single location; sensitive to small leaks at ranges in excess of 500 m
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Low false alarm rate; automated operation - no need for constant supervision
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Localises integrity breaches at the time of detection
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ROV deployable and recoverable; perfect for short monitoring projects
Sentry Sonar is suitable for:
Environmental baselining
Leak detection
Carbon capture and storage


Benefits of Sentry for your asset monitoring operations
Active
Sentry is an active sonar which works by projecting a short-duration high-bandwidth pulse into the water and listening for echoes from any objects such as structures, ROVs or hydrocarbon leaks.
Automatic
The system is fully automated. If a hydrocarbon discharge is detected, it raises the alarm. Data on the leak position is displayed and automatically transmitted to remote monitoring stations.
Flexible
Wired and battery-powered configurations of Sentry IMS provide flexibility in how and when the system can be used. Remote access from onshore enables configuration and monitoring.
Sentry IMS Overview
Covering a 360° field of view, with a detection coverage radius up to 1,200 m, Sentry can detect leaks of monophase gas down to 0.1 litre per minute (equivalent to around 1 barrel of oil per day) or monophase oil to 1 litre per minute (equivalent to 10 barrels of oil per day).
Once installed, Sentry is capable of monitoring over one billion cubic feet of seawater.
Two configurations of Sentry are available. Mounted on a lander, Sentry-W connects into your asset’s existing power and communication seafloor infrastructure. It will run autonomously providing alerts only when its on-board processing has ascertained a positive detection and classification of a leak. Remote access onshore is configurable for multiple users.
Where no infrastructure is available, Sentry-B – a standalone battery operated system – can be lander-deployed, complete with subsea data processing. At preset intervals, or where a leak event is detected, summary data is transmitted using a 6G acoustic modem to a surface transceiver for onward transmission to shore via radio or satellite. Surface transceivers and satellite communications systems can be mounted on a moored buoy, integrated into an unmanned surface vehicle (USV), or positioned over the side of a vessel, rig or floating production system.
Mobile leak detection
For inspecting greater lengths of subsea assets, such as trunk pipelines, our compact yet high-performance Solstice side scan-sonar containing patented automatic target recognition (ATR) algorithms can be integrated into an AUV to provide detection and location of any containment losses of oil or gas.
CCS site monitoring
Why invest in Sentry IMS?
Design
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Wired and battery-powered Sentry IMS options
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Fully autonomous alarms
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Multiple sonar heads can be interfaced together to increase coverage
Typical System Set Up
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Sonar or multiple sonar heads
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Sonar processor (SP)
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Command workstation (CWS)
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Sentry software
Performance
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Man portable sonar head (or networked multiple sonar heads), cabling (including fibre option), junction boxes, shelters
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Deployment options: lightweight seabed frame, seabed stand, rail and trolley mount, vessel through-hull/over-the-side, cable suspension, fixed bracket
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Sonar processor, command workstation, software
Support
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Work side-by-side with our projects and applications group from concept to installation
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Systems are manufactured and tested before delivery at our world-class in-house facilities
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Highly experienced field personnel can be on hand to ensure even the most complex systems are commissioned safely
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24-hour support, whenever and wherever you are in the world