DSL-230M Smoke Density Monitor-web #2LR_Type_Approved_295

With Port Authorities around the world increasingly regulating emissions from ships, the DSL-230M Smoke Density Monitor is an optical instrument specifically designed to measure the concentration of smoke and particulate emissions within the marine industry.

The DSL-230M 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. When calibrated against standard reference measurements, this reduction in intensity can be used to calculate the smoke density and present a reading in mg/m³.


  • Lloyds Type Approved smoke density monitor designed specifically for the marine industry
  • In situ measurement directly in exhaust gas flow
  • Measurement reading as mg/m³ (when calibrated against standard reference measurements)
  • Modulated green LED source for long lifetime stability and immunity to ambient light
  • ‘Intelligent’ sensor so no requriement for a local control unit
  • Choice of interface options enabling easy integration into ship’s control system
  • Optional Operator Interface with panel mount configuration


  • Simple to install, commission and operate with an excellent reliability record
  • Rugged design with no moving parts so low maintenance
  • Latched head design to enable ease of access to optics for preventative maintenance
  • Free utility software for PC based set-up, control and data logging



For further information and technical specifications about this product please download a product brochure alternatively contact us via phone or email and a member of our team will be happy to help.

Request a quote…

If you would like a quote for any of our products or services please click below and leave your details.

We have used DynOptic equipment in multiple applications. The instruments are operating to the Customer’s complete satisfaction, fully compliant to their technical specification.

Bryan Divall
Twin-Tek Pte Ltd., Singapore

DynOptic Systems

SM-202M – long established smoke monitor for measuring visible opacity and smoke emissions in marine boiler and diesel engine exhausts gases.
DSL-220 MkIII – traditional single pass opacity monitor for measuring visible opacity (0 – 100 %) in combustion and air filtration processes.
DSL-330 MkIII - standard double pass particulate monitor for measuring particulate density (mg/m³) in combustion and air filtration processes.