Interim Measures for Small Marine Diesel Engines - 2017 - SSB No.: 02/2017

This bulletin replaces Ship Safety Bulletin No. 07/2016

RDIMS No.: 12525072
Date (Y-M-D) : 2017-01-24
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This bulletin explains Transport Canada’s interim measures regarding compliance with IMO Tier III nitrogen oxides emissions standards set out in the Vessel Pollution and Dangerous Chemicals Regulations (the Regulations).


This bulletin applies to Canadian vessels, that voyage within Canadian waters with a combined nameplate propulsion power of less than 750 kW, installing a small marine diesel engine with a power rating between 130 kilowatts and 750 kilowatts, that must comply with subsection 110.3 (4) of the Regulation.


In early fall of 2015, marine engine suppliers indicated that marine diesel engines under 750 kW compliant with the IMO Tier III Nitrogen Oxides (NOx) Standards would not be available from engine manufacturers by January 1, 2016.

In addition to the non-availability of compliant engines, the Canadian small vessel industry had concerns with the options available to vessel owners to meet the current engine emission requirements.

In response, Transport Canada issued SSB 07/2016 to allow non-compliance with the IMO Tier III NOx emission standards until January 1, 2017, as long as the engine installed met IMO Tier II or US Environmental Protection Agency Tier 3 emission standards.

During this period, Transport Canada chose Alion Canada to review the application of IMO Tier III NOx standards on small marine diesel engines. This review examined:

  • The availability of compliant engines;
  • Current emission abatement technologies; and
  • The technical challenges of small vessels.

The Alion Canada study concluded that IMO Tier III NOx standards would be possible, but:

  • Small vessels would have some difficulty implementing the expected technology to comply (selective catalytic reduction–SCR).
  • Only a limited number of engine manufacturers plan to produce smaller marine diesel engines to meet IMO Tier III NOx standards during 2017 and these new engines would not cover the full applicable power range of 130 to 750 kilowatts for the Tier III NOx standards.

Continuation of Interim measures

Transport Canada will not require compliance with the IMO Tier III nitrogen oxides emissions standards set out in subsection 110.3 (4) of the Regulations, until January 1, 2018, for Canadian vessels IF the marine diesel engine with a power ratings between 130 kilowatts and 750 kilowatts:

  1. Meets the IMO Tier II nitrogen oxides emissions standards set out in subsection 110.2 (3) of the Regulations;


  1. Complies with the United States Environmental Protection Agency Tier 3 emission standards for marine diesel engines set under Title 40, section 1042.101, of the Code of Federal Regulations of the United States for Category 1 engines.

While these interim measures are in place, Transport Canada will continue to monitor the availability of IMO Tier III NOx marine diesel engines from manufacturers.


  1. Air Emissions
  2. Nitrogen Oxides
  3. Enforcement
  4. Pollution Prevention

Questions concerning this Bulletin should be addressed to:

Environmental Protection
Transport Canada
Marine Safety and Security
Tower C, Place de Ville
10th Floor, 330 Sparks Street
Ottawa, Ontario K1A 0N8

Contact us at: or 1-855-859-3123 (Toll Free).

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