dive boat

Nitrogen oxide (NOx) emission requirements have applied to marine diesel engines (with a power output of greater than 130kW) installed on Australian vessels—including domestic commercial vessels (DCVs)—since 2007.

These requirements do not apply to vessels constructed prior to that time—except when the engine has been replaced with a non-identical engine  or has since undergone a major conversion.

Tier I NOx emission limits apply to marine diesel engines installed on Australian vessels constructed from 2007 until 2011 and to pre-2007 engines that underwent a major conversion during that period.

Marine diesel engines installed on vessels constructed after 1 January 2011 and engines that undergo a major conversion from this date must meet the less polluting Tier II limits (except where the engine is an identical replacement  of a pre-2011 engine).

Marine diesel engines must comply with the NOx emission limits as described above and vessels must carry an engine international air pollution prevention (EIAPP) certificate and technical file for each engine, except as provided for under Exemption 44, as described below.

    Exemption from holding an EIAPP certificate and technical file

    Owners and operators of DCVs in Australia are exempt from holding an EIAPP certificate and technical file provided they hold acceptable alternative evidence that demonstrates each installed engine (with a power output above 130kW) is likely to comply with the applicable NOx emission limit or tier.

      This exemption applies automatically to engines installed on DCVs before 1 April 2022, and is conditional on the following:

      • The engine is not modified from the original equipment manufacturer's tested configuration.
      • A copy of the acceptable alternative evidence must be available on board for inspection by AMSA or a marine safety inspector. 

      The exemption does not apply for vessels on overseas voyages

      DCV’s built overseas and delivered under their own propulsion as a regulated Australian vessel, or vessels intending to undertake an overseas voyage (for example, for dry-docking) must carry on board an EIAPP certificate and technical file for each installed engine with a power output of greater than 130kW. 

      The exemption is not applicable if the engine already has a valid EIAPP certificate.

      Acceptable alternative evidence

      Acceptable evidence is any of the documents listed below. They must show that the emissions of nitrogen oxides from the engine are likely to be within the relevant NOx emission limit or tier. The evidence needs to be kept available for inspection by AMSA. 

      • An engine manufacturer’s product manual.
      • Correspondence from the engine manufacturer.
      • Other emission certification issued by, or on behalf of an IMO member state.
      • A statement of compliance issued by a recognised organisation.
      Identical replacement engines

      An engine is an identical replacement to the original engine if it is the same in respect to all of the following: 

      • design
      • model
      • rated power
      • rated speed
      • use
      • number of cylinders
      • fuel system type

      If you are replacing an engine that is not an identical replacement for operation in Australian waters you must ensure the replacement engine is certified as compliant with the MARPOL Tier II NOx emission limits. 

      Major conversions

      A major conversion means a modification of a marine diesel engine in one of the following situations: 

      • The engine is replaced by a marine diesel engine that is not identical (see above) or an additional marine diesel engine is installed.
      • Any substantial modification, as defined in the revised NOx Technical Code 2008, is made to the engine.
      • The maximum continuous rating of the engine is increased by more than 10% compared to the maximum continuous rating of the original certification of the engine.
      Engines used for emergencies

      The NOx emission regulations do not apply to the following marine diesel engines:

      • Those intended to be used solely for emergencies.
      • Those used to power any device or equipment intended to be used solely for emergencies on the vessel on which it is installed.
      • Those installed in lifeboats intended to be used solely for emergencies.