Engine compliance and product quality are different
MARPOL Annex VI Regulation 13 sets requirements for NOx emissions from relevant marine diesel engines. ISO 18611 describes AUS40 product requirements. Buying a reagent alone does not certify the vessel, engine or SCR installation.
Check applicability for the vessel and route
Tier III applicability depends on the designated NOx emission control area, relevant construction dates, engine circumstances and any applicable exceptions. A sulphur ECA designation does not by itself mean the same NOx requirements apply.
Use the current IMO requirements, the vessel’s approved technical documentation and flag/class advice for voyage decisions. ECA designations and effective dates change; this page is not a substitute for a route-specific compliance review.
What procurement can prepare
- The OEM-specified reagent and quality standard.
- Expected SCR operating hours and the documented dosing/consumption plan.
- Usable onboard stock, storage limits and the planned replenishment port.
- Batch CoA, MSDS and delivery records for the supply.
Plan supply before the call
Allow time to review product documents, quantity and delivery access. See the pre-voyage supply checklist.
References
Common questions
Does buying certified AUS40 make my vessel Tier III compliant?
No. MARPOL Annex VI Regulation 13 applies to the engine and its installation. A certified reagent is necessary for an SCR system to work as approved, but compliance rests on the approved engine and SCR installation and how it is operated.
Where do IMO Tier III NOx limits apply?
In designated NOx Emission Control Areas, subject to the vessel’s construction date, the engine circumstances and any applicable exceptions. Designations and effective dates change, so check the current IMO requirements and your flag or class advice for the specific route.
Is a sulphur ECA the same as a NOx ECA?
No, and conflating them is a common error. A sulphur emission control area designation does not by itself mean the same NOx requirements apply. They are separate designations with separate scopes.
What should procurement prepare for a Tier III vessel?
The OEM-specified reagent and quality standard, the documented dosing rate and expected SCR operating hours, usable onboard stock and storage limits, the planned replenishment port, and the batch CoA, MSDS and delivery records for each supply.