Marine Monitors

Marine Monitor

In recent years, new regulations have been introduced governing emissions from ships. With the International Maritime Organization (IMO) adopting Annex VI of MARPOL designed to limit sulphur oxides (SOx), nitrous oxides (NOx) and particulate matter emissions, as well as introducing emission control areas (ECAs) to reduce emissions of those air pollutants further in designated sea areas, ship owners/operators can face hefty fines for failing to meet these new requirements on the 'polluter pays' principle.

Ships emit more particulate matter (PM) per unit of fuel consumed than other fossil fuel combustion sources due to the quality of fuel used. Stringent rules against ships exhausting black smoke within sight of shore - notably in regions such as Alaska and Hawaii, where cruise ships and tankers are particularly vulnerable - have been introduced and are backed up by 'spotters' employed by authorities to report any infringements. Penalties extend from warnings and fines to future banishment of guilty tonnage from the area.

Marine Monitor

Therefore, effective smoke monitoring is becoming increasingly important and installing a smoke opacity monitor is one way of providing a warning if the combustion of a boiler, incinerator or engine is poorly adjusted thus leading to the emission of black smoke. This will also help to protect ship-owners against heavy fines as well as potential damage to the ship's and company's image.

Dynoptic smoke monitors measure the density of the smoke using the light transmission technique to measure the visible opacity of exhaust gas in a duct, stack or flue, in which a high intensity light beam is projected across the stack. Any smoke or particulate present will attenuate the transmitted light and the decrease in light intensity, due to absorption and scattering, is measured. The higher the level of smoke present, the more light lost and therefore, the greater the opacity.

DynOptic currently offers three different particulate monitors for monitoring marine emissions:

SM-202M Smoke Opacity Monitor

Dynoptic Systems

SM-202M Smoke Opacity Monitor

With Port Authorities around the world increasingly regulating emissions from ships, the SM-202M Smoke Opacity Monitor is an optical instrument specifically designed to measure the visible opacity of smoke emissions within the marine industry.

The SM-202M uses the single pass light transmission measurement technique, with Transmitter/Receiver arrangement. A light beam emitted from the Transmitter passes across the stack to a Receiver, which measures the intensity of the received light. Increased smoke density in the stack gas attenuates the transmitted light and causes the intensity of the received light to fall. This reduction in intensity is measured and presented as % opacity. The higher the level of smoke present, the more light lost and therefore, the greater the opacity.

System Layout


  • In situ measurement directly in exhaust gas flow
  • Measurement reading as % opacity, smoke density as mg/m3 or Ringelmann
  • Modulated green LED source for long lifetime stability and immunity to ambient light
  • Rugged 316 stainless steel construction
  • 'Intelligent’ sensor so no requriement for a local control unit
  • Panel mounting Operator Interface enabling local monitoring and control of the instrument
  • Choice of interface options enabling easy integration into ship's control system


  • Excellent reliability record with more than 2000 instruments installed on ships worldwide
  • Simple to install, commission and operate
  • Easy to set-up via local Operator Interface
  • Rugged design with no moving parts so low maintenance
  • Latched head and lid design to enable ease of access for installation and maintenance

Optional Accessories

  • Mounting flange installation kit
  • Laser alignment tool to assist with installation
  • Air purge blower kit (110 Vac / 230 Vac / 415 Vac
  • Compressed air purge kit
  • Reference filters for routine calibration check of the instrument

For further information about any of our products please call or e-mail and a member of our team will be happy to help.