One billion cubic feet of seawater, 360° of coverage, one Sentry.

Key benefits

• Developed from our field proven detection, localisation and classification sonar technology
• Provides 360 degree, high volume coverage from a single location; sensitive to small leaks at ranges of over 500 m
• Low false alarm rate; automated operation – no need for constant supervision
• Localises integrity breaches at the time of detection
• ROV deployable and recoverable; perfect for short monitoring projects

Sentry is the answer to your subsea monitoring challenges. It 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. 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 your remote onshore monitoring stations. Multiple users can access and update the system remotely, allowing you to make best use of your time and resources. It is suitable for:

• Environmental surveys
• Pipeline and spool piece monitoring
• Leak detection
• Carbon capture and storage
• Automatic, wide-area leak monitoring

Active, automatic, flexible – Sentry for your asset monitoring operation needs

How it works

Developed by our sister company Wavefront Systems, manufactured and commercialised by Sonardyne, Sentry covers a 360° field of view, with a detection coverage radius up to 1,200 m and is capable of monitoring over one billion cubic feet of seawater. It 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).

Wired and battery-powered configurations of Sentry IMS provide flexibility in how and when you can use the system. Mounted on a lander, Sentry-W connects into your asset’s existing power and communication seafloor infrastructure. It will run autonomously, providing alerts to your remote operations centre only when its on-board processing has determined a positive detection and classification of a leak.

Where no infrastructure is available, Sentry-B (a standalone battery operated system) can be lander-deployed, complete with subsea data processing, close to your assets. At pre-set intervals, or when a leak event is detected, summary data is transmitted using a 6G acoustic modem to a surface transceiver for onward transmission to your remote operations centre. Surface transceivers and satellite communications systems can be mounted on a moored buoy, integrated into an unmanned surface vehicle (USV), or fitted to any other surface asset.

Common applications

CCS site monitoring

Containment failure at an offshore carbon capture and storage (CCS) site, while highly unlikely, is of significant concern to regulatory bodies, operators and environmental groups. We have developed the capability to detect and monitor any leakage at high risk locations combining Sentry sonar and chemical sensors on a lander to deliver sensitive and reliable automated leak detection capability across wide areas.

Speak to us about your CCS requirements.

Offshore hydrogen production and storage site monitoring

As we transition towards a net zero world, hydrogen is set to play a larger role in our energy system. This includes offshore production and then transport via pipeline to shore. It may also include underground storage, including in sites offshore, similar to how natural gas has been stored. Containment monitoring and asset integrity assurance are just as important here and Sentry provides an ideal solution. Contact us to find out more.

Need mobile, more targeted monitoring over distance?

For inspecting greater lengths of subsea assets, such as your trunk pipelines, our compact yet high-performance Solstice side scan-sonar containing powerful automatic target recognition (ATR) algorithms can be integrated into an AUV to provide detection and location of any containment losses of oil or gas. Find out more here.