Conditions to be met in order for a diesel engine not to be required to comply with the NOx Tier emission limits

1. NO_x Tier III requirements in the North Sea Emission Control Area

As from 1 January 2021, the NO_x Tier III requirements will be applicable in the North Sea Emission Control Area (hereafter referred to as NSECA). This implies that diesel engines with a power output of more than 130 kW installed on ships constructed on or after 1 January 2021 and operating in the NSECA on or after this date shall comply with the NO_x Tier III emission requirements as stipulated in section 12 of the Environmental Safety Regulations, cf. MARPOL Reg. VI/13.5.1.1.

 

The above-mentioned NO_x Tier III requirements also apply in the event of a major conversion of a diesel engine on or after 1 January 2021 on ships operating in the NSECA on or after 1 January 2021.

 

2. Definitions

 

2.1 The wording “ship constructed” means a ship the keel of which is laid or which is at a similar stage of construction.

 

2.2 The wording “a similar stage of construction” means the stage at which:

.1 construction identifiable with a specific ship begins; and

.2 assembly of that ship has commenced comprising at least 50 tonnes or 1 % of the estimated mass of all structural material, whichever is less.

 

2.3 In this context, the wording “major conversion” means that:

.1 the engine is replaced by a marine diesel engine or an additional marine diesel engine is installed, or

.2 any substantial modification, as defined in the revised NO_x Technical Code 2008, is made to the engine, or

.3 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.

 

Documentation required for the Norwegian Maritime Authority to be able to determine whether the NO_x Tier III emission limits must be met

Under certain conditions (see items 3.1 to 3.3 below) the legislation allows for the possibility that a diesel engine with a power output of more than 130 kW installed on a ship constructed or adapted on or after 1 January 2021 is not required to comply with the NO_x Tier III requirements that apply to ships operating in the NSECA on or after this date.

When the company (yard) presumes that the NO_x Tier III requirements do not have to be met, documentation as stipulated in items 3.1, 3.2 or 3.3 below shall be submitted to the Norwegian Maritime Authority (NMA) for review.

 

3.1 Replacement with identical diesel engine

A diesel engine with a power output of more than 130 kW which is replaced with an identical diesel engine on or after 1 January 2021, cf. section 12 of the Environmental Safety Regulations, cf. MARPOL reg. VI/13.1.1.2, is not required to meet the NO_x Tier III limits that apply in the NSECA on or after 1 January 2021.

The shipping company must provide documentation that the diesel engine is replaced by an identical diesel engine. The contents of the documentation to be submitted for review are found in IMO’s unified interpretations item 61 to MARPOL Annex VI.

 

3.2 Replacement of a diesel engine with a non-identical marine diesel engine

If a replacement diesel engine with a similar power output, complying with the NO_x Tier III requirements, is not commercially available on or after 1 January 2021, cf. section 12 of the Environmental Safety Regulations, cf. MARPOL reg. VI/13.2.2, the replacement diesel engine is not subject to the NO_x Tier III requirements that apply to the NSECA on or after 1 January 2021. In such cases, the NO_x Tier II requirements will apply.

The shipping company must document the search for a compatible NO_x Tier III engine and why the closest available engine with respect to size or performance is not appropriate for installation on board the ship.  The search should include engines produced by manufacturers other than the manufacturer of the original engine. The documentation will be reviewed by the NMA. The documentation and the NMA’s confirmation that the replacement engine does not have to comply with the NO_x Tier III requirements must be kept on board together with the engine’s EIAPP certificate.

 

3.3 Diesel engines installed on ships with a combined nameplate diesel engine propulsion power of less than 750 kW

Diesel engines with a power output of more than 130 kW installed on ships with a combined nameplate diesel engine propulsion power of less than 750 kW that are constructed on or after 1 January 2021 and that will operate in the NSECA are not required to comply with the NO_x Tier III requirements, provided that design or construction limitations of the ship cause non-compliance with the NO_x Tier III requirements, cf. section 12 of the Environmental Safety Regulations, cf. MARPOL regulation VI/13.5.2.2.

 

Examples of conditions which should be documented and which, in the opinion of the NMA, imply that design or construction limitations of the ship cause non-compliance with the NO_x Tier III requirements:

a) the engine must be fitted with a NO_x-reducing device that due to its size cannot be installed on the limited space on board;

b) heat output from a NO_x-reducing device has a negative effect on the ship's structure, design or equipment, and further ventilation or isolation of the engine room is not possible.

 

4. Documentation requirements

The legal basis for the NMA's documentation requirement included in items 3.1, 3.2 and 3.3 above is stipulated in section 2 of the Environmental Safety Regulations.

Having received the documentation required, the NMA will carry out a review and determine whether or not the NO_x Tier III requirements will apply to the relevant engine with a power output of more than 130 kW (as referred to in items 3.1, 3.2 or 3.3 above) installed on a ship constructed or after 1 January 2021 and operating in the NSECA.