Substances barred from shipboard incineration and the approval and operating conditions on the incinerator (MARPOL Annex VI Regulation 16)

Say sludge oil from the engine room and garbage collected on deck are about to go into the incinerator together. Three things bite at once: what has to be taken out, whether burning is allowed where the ship is now, and whether that incinerator may be run as it stands. MARPOL Annex VI Regulation 16 settles the three in separate sentences.

The structure of the provision is simple. It first lists what cannot be burned, then attaches equipment and operating conditions to what can. And it puts a restriction on place along one route only.

Incineration is allowed only inside a shipboard incinerator, and the exception opens in one place

1 Except as provided in paragraph 4 of this regulation, shipboard incineration shall be allowed only in a shipboard incinerator.

The provision pins the permitted place to a piece of equipment. Burning waste may be done only inside a shipboard incinerator. Feeding waste into a boiler or the main engine to burn it runs into this sentence.

There is a single exception, in paragraph 4. Where the text opens that exception comes further down. What matters here is that there is one. No other paragraph widens the place where incineration may happen.

The list of what cannot be burned splits on composition and on origin

2 Shipboard incineration of the following substances shall be prohibited: .1 residues of cargoes subject to Annex I, II or III or related contaminated packing materials; .2 polychlorinated biphenyls (PCBs); .3 garbage, as defined by Annex V, containing more than traces of heavy metals; .4 refined petroleum products containing halogen compounds; .5 sewage sludge and sludge oil neither of which is generated on board the ship; and .6 exhaust gas cleaning system residues.

The six items sit side by side, but they are not decided on the same test.

The first item is cargo residues. Annexes I and II and III each set out a separate route for disposing of those substances. Leaving incineration open would let a ship bypass the route, so it is closed. Contaminated packing materials come along with them.

The third item turns on content rather than on the substance. Garbage under Annex V still falls out of incineration once it carries more than traces of heavy metals. The same bag of garbage is decided by what is inside it.

The fourth item works the same way. A refined petroleum product is something that will burn on its own account, but once halogen compounds are in it, it moves into the prohibited list. The question shifts from whether it burns to what is mixed into it.

The fifth item runs on a different axis. The substances are sewage sludge and sludge oil, and the condition is neither of which is generated on board the ship. Only what was taken on from shore or from another ship is prohibited. The same substance generated on the ship is dealt with separately in paragraph 4.

The sixth item is exhaust gas cleaning system residues. Burning what was taken out of the exhaust puts it back where it was taken from.

And there is one conditional item outside the list.

3 Shipboard incineration of polyvinyl chlorides (PVCs) shall be prohibited, except in shipboard incinerators for which IMO Type Approval Certificates have been issued.

For PVCs the condition that lifts the prohibition sits on the equipment side. An incinerator for which IMO Type Approval Certificates have been issued may burn them, and without one they are barred like the six items above. So this decision is not made where the waste is sorted. It is made where the incinerator’s certificate is checked.

Sludge generated on board may be burned outside the incinerator, but not inside a port

4 Shipboard incineration of sewage sludge and sludge oil generated during normal operation of a ship may also take place in the main or auxiliary power plant or boilers, but in those cases, shall not take place inside ports, harbours or estuaries.

This is the exception paragraph 1 pointed to. Three conditions overlap. The substance has to be sewage sludge or sludge oil, the origin has to be normal operation of that ship, and the place of burning is the main or auxiliary power plant or the boilers.

A restriction on place is then attached. It may not be done inside ports, harbours or estuaries. That restriction bites when burning by this route, not when burning inside the incinerator. The text put the condition on this route alone.

Read it against the fifth item of paragraph 2 and the axis shows. Of the same sewage sludge and sludge oil, what came from outside the ship is prohibited, while what was generated on the ship may be burned if the place is respected. Origin decides it, not the name of the substance.

The requirements on an incinerator split at 1 January 2000

6.1 Except as provided in paragraph 6.2 of this regulation, each incinerator on a ship constructed on or after 1 January 2000 or incinerator that is installed on board a ship on or after 1 January 2000 shall meet the requirements contained in appendix IV to this Annex. Each incinerator subject to this paragraph shall be approved by the Administration taking into account the standard specification for shipboard incinerators developed by the Organization;

The date is used twice. Once for the build date of the ship and once for the installation date of the incinerator. Either one falling after the date is enough for the requirements to bite. Put a new incinerator into an old ship and that incinerator becomes subject to appendix IV. Approval comes with it. The Administration approves, taking into account the standard specification for shipboard incinerators developed by the Organization.

And there is one exclusion.

6.2 The Administration may allow exclusion from the application of paragraph 6.1 of this regulation to any incinerator installed on board a ship before 19 May 2005, provided that the ship is solely engaged in voyages within waters subject to the sovereignty or jurisdiction of the State the flag of which the ship is entitled to fly.

Incinerator	Appendix IV and Administration approval
On a ship constructed on or after 1 January 2000	Apply
Installed on board on or after 1 January 2000	Apply whatever the build date of the ship
Installed on board before 19 May 2005	The Administration may allow exclusion

The exclusion is not automatic. The text says only that the Administration may allow it, and it attaches the trading area as a condition. The ship has to be engaged solely in voyages within waters subject to the sovereignty or jurisdiction of its own flag State. The moment the ship goes on an international voyage, the exclusion loses its ground.

An approved incinerator cannot be fed once the temperature drops

7 Incinerators installed in accordance with the requirements of paragraph 6.1 of this regulation shall be provided with a manufacturer’s operating manual, which is to be retained with the unit and which shall specify how to operate the incinerator within the limits described in paragraph 2 of appendix IV of this Annex. 8 Personnel responsible for the operation of an incinerator installed in accordance with the requirements of paragraph 6.1 of this regulation shall be trained to implement the guidance provided in the manufacturer’s operating manual as required by paragraph 7 of this regulation. 9 For incinerators installed in accordance with the requirements of paragraph 6.1 of this regulation the combustion chamber gas outlet temperature shall be monitored at all times the unit is in operation. Where that incinerator is of the continuous-feed type, waste shall not be fed into the unit when the combustion chamber gas outlet temperature is below 850°C. Where that incinerator is of the batch-loaded type, the unit shall be designed so that the combustion chamber gas outlet temperature shall reach 600°C within five minutes after start-up and will thereafter stabilize at a temperature not less than 850°C.

The three paragraphs point at the same object: an incinerator installed in accordance with paragraph 6.1. That incinerator comes with a manufacturer’s operating manual, and the manual has to stay on board with the unit. The person responsible has to be trained on the guidance in it. And while the unit is running, the combustion chamber gas outlet temperature has to be watched continuously.

The temperature condition splits by how the unit is loaded.

• Continuous-feed type: waste is not fed in when the combustion chamber gas outlet temperature is below 850°C. The act of feeding is what is blocked.
• Batch-loaded type: the unit has to be designed so the temperature reaches 600°C within 5 minutes of start-up and then stabilizes at not less than 850°C. Here the condition sits on the design of the equipment, not on what the operator does.

The same 850°C does different work in the two types. In the continuous-feed type the temperature is the threshold for feeding. In the batch-loaded type it is a value the design has to meet. And the monitoring the text asks for runs the whole time the unit is in operation. Looking once at start-up does not satisfy paragraph 9.

Worth confirming

The passages above come from printed pages 29 to 31 of the revised Annex VI adopted by resolution MEPC.328(76).

Regulation 16.5 pins down two further things. One is that the prohibitions on incineration at sea under the 1972 Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter and its 1996 Protocol are not affected by this regulation. The other is that the regulation does not preclude alternative design shipboard thermal waste treatment devices that meet or exceed its requirements. So where a device other than an incinerator is used, Regulation 16 alone will not settle the question.

The content of appendix IV sits outside this extract. What the requirements referred to in paragraph 6.1 are, and what the limits in paragraph 2 of appendix IV mentioned in paragraph 7 are, have to be read there. Approval of an incinerator and the granting of an exclusion are for the Administration, and whether a port restricts incineration more narrowly is for that port State’s law.