The two sulphur limits in MARPOL Annex VI regulation 14 and the record a fuel changeover leaves

Say a ship is running towards the boundary of an emission control area. The engine room has started the changeover to low sulphur fuel oil, and there is still room before the line. What the provision checks at that point is not that a changeover took place. It is when and where the changeover finished.

Regulation 14 of MARPOL Annex VI covers sulphur oxides and particulate matter. There are two limits, and the moment of crossing between them is made to survive as a record. This article follows the difference between the two limits and the items the provision says to write down.

The general limit catches fuel carried for use, not only fuel burned

The sulphur content of fuel oil used or carried for use on board a ship shall not exceed 0.50% m/m.

Two words sit side by side: used or carried for use on board a ship. The fuel being burned and the fuel carried in order to burn it are caught together. So the judgement is settled at the tank, not at the funnel.

Paragraph 2 backs the limit up on the system side. The worldwide average sulphur content of residual fuel oil supplied for use on board ships is monitored, taking into account the guidelines developed by the Organization.

Inside an emission control area the limit drops to 0.10%

While a ship is operating within an emission control area, the sulphur content of fuel oil used on board that ship shall not exceed 0.10% m/m.

What paragraph 4 catches is used on board and nothing else. Carriage is not in it. What it fixes instead is the stretch over which it applies: while the ship is operating within that area. Paragraph 3 defines an emission control area as a sea area including any port area, and four are named there.

• the Baltic Sea area
• the North Sea area
• the North American Emission Control Area
• the United States Caribbean Sea Emission Control Area

The first two take their definitions from other Annexes. The last two are drawn by the coordinates in appendix VII to this Annex.

Item	General sea areas	Emission control areas
Limit	0.50% m/m	0.10% m/m
What is caught	use, and carriage for use	use
Basis	regulation 14 paragraph 1	regulation 14 paragraph 4

The changeover procedure has to leave time for the system to flush

Those ships using separate fuel oils to comply with paragraph 4 of this regulation and entering or leaving an emission control area set forth in paragraph 3 of this regulation shall carry a written procedure showing how the fuel oil changeover is to be done, allowing sufficient time for the fuel oil service system to be fully flushed of all fuel oils exceeding the applicable sulphur content specified in paragraph 4 of this regulation prior to entry into an emission control area.

The scope is fixed first: ships using separate fuel oils to comply with paragraph 4. Those ships have to carry a written procedure when they enter or leave an emission control area.

The procedure holds two things. How the changeover is done, and how enough time is left before entry for the fuel oil service system to be fully flushed of fuel above the limit.

How long the flushing takes follows from the volume of the service system and the rate of consumption. So the procedure is a document for one ship, not one shared across the fleet.

What the record holds is the time the changeover finished and the position then

The volume of low sulphur fuel oils in each tank as well as the date, time and position of the ship when any fuel oil changeover operation is completed prior to the entry into an emission control area or commenced after exit from such an area shall be recorded in such logbook or electronic record book as prescribed by the Administration.

The sentence fixes the items.

• the volume of low sulphur fuel oils in each tank
• the date and time of the changeover operation
• the position of the ship at that time

Which time gets written down splits by direction.

Item	Entering the area	After leaving the area
Time recorded	when the changeover was completed	when the changeover was commenced
The words used	completed prior to the entry	commenced after exit

The directions are opposite because the stretch the limit applies to is inside the area. On the way in, the time everything was switched over has to fall before the line. On the way out, the time the switch back started has to fall after it. The entry goes in the logbook or electronic record book prescribed by the Administration.

Proof that the limit was met comes from supplier documents and from samples

The sulphur content of fuel oil referred to in paragraph 1 and paragraph 4 of this regulation shall be documented by its supplier as required by regulation 18 of this Annex.

On the supplier side, the sulphur content is documented as required by regulation 18 of this Annex. It is not paperwork the ship produces for itself.

On the ship side, samples answer. Where the competent authority of a Party requires the sample to be analysed, it is done in accordance with the verification procedure in appendix VI to this Annex.

The sample shall be sealed by the representative of the competent authority with a unique means of identification installed in the presence of the ship’s representative. The ship shall be given the option of retaining a duplicate sample.

The seal goes on in front of the ship’s representative. And the ship is given the option of retaining a duplicate sample. Being an option, it does not arrive unless it is asked for. Without a duplicate on board, the ship has nothing of its own to put against the analysis later.

Sampling points and newly designated areas carry deadlines of their own

For a ship constructed before 1 April 2022, the sampling point(s) referred to in paragraph 10 shall be fitted or designated not later than the first renewal survey as identified in regulation 5.1.2 of this Annex on or after 1 April 2023.

A ship subject to regulations 5 and 6 of this Annex has to fit or designate a point where a representative sample of the fuel oil in use can be drawn. A ship constructed before 1 April 2022 has until the first renewal survey on or after 1 April 2023. The requirement does not reach the fuel oil service system of a low-flashpoint fuel used for propulsion or operation on board.

A newly designated area carries a different deadline.

During the first 12 months immediately following entry into force of an amendment designating a specific emission control area under paragraph 3 of this regulation, ships operating in that emission control area are exempt from the requirements in paragraphs 4 and 6 of this regulation and from the requirements of paragraph 5 of this regulation insofar as they relate to paragraph 4 of this regulation.

During the first 12 months after the amendment enters into force, ships operating in that area fall outside the requirements of paragraphs 4 and 6. Paragraph 5 falls away with them so far as it relates to paragraph 4. This relief opens only where an area is newly designated.

Worth confirming

The passages above come from regulation 14 of MARPOL Annex VI (the consolidated text adopted by resolution MEPC.328(76)). What regulation 14 settles is the limits and the record. Which book and which columns the entries go in is for the Administration to prescribe.

Whether the carriage restriction in paragraph 1 has exceptions is settled elsewhere in Annex VI, not in regulation 14. What goes into the supplier’s document sits in regulation 18. Neither is covered here. The list of emission control areas can grow by amendment. Whether a flag State or a port State sets stricter requirements outside this regulation has to be checked in the law of that country.