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Underwater methane sensor


CONTROS HydroC CH4 subsea / underwater methane sensor

The CONTROS HydroC® CH4 sensor is a unique subsea / underwater methane sensor for in-situ and online measurements of CH4 partial pressure (p CH4). The versatile CONTROS HydroC® CH4 provides the perfect solution for the monitoring of background CH4 concentrations and for long-term deployments.

Operating principle

Dissolved CH4 molecules diffuse through a custom made thin film membrane into the internal gas circuit leading to a detector chamber, where the CH4 concentration is determined by means of Tunable Diode Laser Absorption Spectroscopy (TDLAS). Concentration dependent laser light intensities are converted into the output signal from calibration coefficients stored in firmware and data from additional sensors within the gas circuit.

High accuracy and stability

Due to their narrow line-width, the Tunable Diode Laser Detectors have a high accuracy and an ideal selectivity for methane molecules. In addition, they feature a large dynamic range covering background partial pressures up to 40 matm. All detectors are subject to an individual calibration and an in depth quality check in our QA lab before they are integrated into our sensors. The quality of the calibration is then verified individually in calibration tanks. The sensor is stable over a long time as the detector tunes the laser to CH4 absorbing and non-absorbing wavelengths for each measurement thus compensating for potential drift influences.


  • High accuracy and low detection limit of background concentration
  • Large measuring range
  • Optimal long-term stability
  • Ideal methane selectivity
  • Non-consuming CH4 measurement
  • Very robust, can be used in water depths up to 3000 meters
  • User-friendly 'Plug & Play' principle; all required cables, connectors and software are included


  • Analogue output: 0 V - 5 V
  • Internal data logger
  • External battery packs
  • ROV and AUV installation packages
  • Profiling and mooring frames
  • External pump (SBE-5T or SBE-5M)
  • Easy deployment together with a CONTROS HydroFlash® O2


A wide range of available accessories ensures that each of the CONTROS HydroC® CH4 sensors can be adapted to meet customers' requirements. Underwater pumps and different flow head designs are the most popular options, which ensure fast response times. An antifouling head is used under conditions with significant biofouling pressure. The internal data logger can be used in conjunction with the CONTROS HydroC®'s flexible power management features and the CONTROS HydroB® battery packs to conduct unattended long-term deployments.

Services & Aftermarket Support

24/7 Technical Support

Our 24/7 technical support team is there to help at any time, day or night, wherever your vessel is. We will manage your call from the time it is received to the time the issue is resolved.

The team has direct access to the experts in our product centres, should additional support be required, and for the more complex issues a product specialist will be assigned to you. Our priority is to get the right expertise quickly matched with the issue to provide the answers you need.

Contact us

The following contact information will put you through to our global support team:


We understand the importance of having the right parts, available in the right place, at the right time.

We have streamlined our operations to reduce lead-times and increase spares availability.

Contact us

Our 24/7 technical support team is there to help at any time of day or night wherever your vessel is located. They manage your call from the time it is received to the time the issue is resolved.

Contacting any of these numbers will put you through to our global support team:

Our local representatives will respond to your support requirements 24/7. If you want to know more about how our enhanced service delivery will benefit you, please contact our nearest Office.

Product Training

Ensure that your crew is properly and thoroughly trained. This will reduce operational risk, downtime and maximise return on asset investment.

It also enables you to meet regulatory standards, improve crew safety and retain key personnel. In our state of the art training centres qualified and experienced trainers are able to provide your crew with practical training tailored to suit your products, systems and operational requirements. Our instructors can also train your crew on-board your vessel.

From hands on experience on live products in our training centres, to experiencing real life scenarios in our world class simulators all our courses are designed to focus on efficient and safe operation and maintenance of your Kongsberg Maritime equipment.


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  • UNITED STATES, New Orleans

This type of solution is ideal for theoretical training, especially for larger groups. It goes through detailed systems overview including drawings and functionality.

This type of solution is ideal for practical training with focus on maintenance and troubleshooting on actual products. This type of training used together with classroom training can provide a holistic view of complete systems.