Making the invisible visible – towards a “greener” shipping industry.

Green Instruments A/S, Danish company, established in 1999, is one of the leading global companies supplying systems for the marine industry.

Green Instruments develop and manufacture systems and instruments for gas and water analysis, monitoring systems for emission control, hazard detection and machinery protection.

These solutions help vessels to operate in a safer, more efficient, and environmentally friendly way.

IMO & MEPC compliancy towards increasingly stringent emission regulations is standard for our solutions, and strategy is to be one step ahead of future branch requirements.

With +5000 vessels globally operating scrubbers, Green Instruments have managed to become a reliable supplier in many projects.

Our key solutions are our scrubber water monitoring systems with +3500 cabinets installed globally and scrubber emission monitoring systems +400 systems installed globally.


With the new G7200, Green Instruments presents the second generation of CEMS which will monitor the usual gases and also the new ones like SO2, CO2, CH4, CO, N2O, NO2 and NO in order to cope with the requirements of new fuels like LNG, Methanol, Ammonia, various bio-fuels a.o.

The G7200 Multi Gas Monitoring System uses non-dispersive infrared/ultraviolet technology with up to three gas analyzers. It samples from five points, ensuring real-time, efficient monitoring and rapid response to excessive emissions.

Some key advantages:

  • Real time monitoring and documentation of harmful emissions for emission reporting
  • Improved cooling without the use of harmful refrigerants
  • Standard single or dual stack sample conditioning
  • Optional remote access
  • Failsafe zero air system with integrated air treatment unit
  • 5-step filtration
  • Modular design for customizing monitoring profile
  • Up to five sampling points
  • Automatic calibration using internal calibration cells (SO2/CO2)
  • Low gas flow for low filter consumption
  • Easy replacement of consumables by the crew or Green Instruments service support

SMOKE MONITOR : monitoring of smoke density from all kinds of combustion

The G16 Smoke Density Monitor is an advanced monitoring system that measures the particles of smoke and dust in stacks.

Smoke is generated by diesel engines, boilers, incinerators, etc. The system determines the level of particles in the smoke to provide precise combustion data for legal and financial reporting requirements. The G16 Smoke Density Monitor also ensures environmental compliance and measures the full range of opacity (0-100%).

It is compact and simple to install in newbuilds and retrofits.

The G16 Smoke Density Monitor is designed for installation in stacks on board vessels. The robust transceiver consists of a solid green laser, an optical system, and electronics. To provide precise data, a light beam with specific spectral characteristics is projected across the space inside the stack. The amount of light reflected back to the instrument from an installed reflector is compared with the maximum possible return when there is nothing obstructing the beam.

The system includes an HMI module and is available with different interface options. The home screen provides an immediate overview of smoke and dust density inside the stack. This means the crew will be provided with precise combustion data, which they need to report for legal requirements.

The opacity monitoring system provides multiple functions for control, graphic, and data logging and can be installed with an audit module for easy verification.


The G26 Ambient Oil Mist Detector is an opacity meter which is designed to detect oil mist in open spaces.

Oil mist is formed by oil droplets suspended in the air. Oil mists ignite at low temperatures and can cause severe damage such as engine room fires. The oil mist detector acts as a safety alarm, thus helping the crew avoid fires and thereby protecting lives, the environment, and assets.

The G26 has the several decisive advantages, each detector can cover a much larger area & monitor the oil mist in several different locations at the same time. The scanning distance of a detector is from 1 to 15 meters.

OXYGEN ANALYZER : real-time inert gas monitoring

Green Instruments oxygen analyzers provide user-friendly and robust monitoring in marine environments, ensuring accurate and reliable oxygen measurements. Inert gases are gases with a low concentration of oxygen that are used to fill void spaces in and around oil tanks.

Oxygen analyzers are used to prevent combustible atmospheres. Having an oxygen analyzer on board is crucial for enhancing and maintaining vessel safety. Tankers are also required by safety inspectors to document their safety when loading and discharging at ports.

The G3600 Inert Gas Oxygen Analyzing System measures the content of oxygen in inert gas. The system has a very user-friendly and robust design. For uninterrupted operation we offer the double boarded version with two analyzers and two sensors. It is also designed for nitrogen generators with high inlet pressure.

The G36 oxygen analyzer is approved under the European Marine Equipment’s Directive (MED).


The G4130 NOx/O2 Analyzing System is a simple and reliable system that provides precise NOx/O2 combustion data, helping vessels to comply with increasingly stringent emission regulations.

G4310 provides real time measurements of NOx in ppm and O2 in % on wet basis at high temperatures.

Using the G4130 NOx/O2 Analyzing System in combination with an emissions abatement system such as a selective catalytic reduction (SCR) or exhaust gas recirculation system (EGR) will allow constant optimization of fuel combustion, urea injection, and other operating parameters.

Real-time emission data provided by the NOx analyzer is crucial for engine and equipment diagnostics.

WATER MONITORING SYSTEM (WMS) : monitor Pah, turbidity, ph and temperature

The NEW G6200 Water Monitoring System, replace the world-wide famous G6100, is a simple and reliable scrubber water monitoring solution.

Some key features of the new G6200 are :

  • Durable and robust design
  • Designed and certified for the harsh environment
  • Simple operation and installation with a minimum footprint
  • On site calibration
  • New G6111 Pah sensor technology, 3 yrs lifetime, extended warranty
  • Covers a broad range of temperatures, pressures, and flow rates
  • Low cost of ownership
  • The system is fully compliant with resolution MEPC. 340(77).

Marine products that innovate the Market. 54 Years on the Sea | 1969 – 2024

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