Incinerator Operations
Permitted materials, operating limits and temperature monitoring; relevant records and ash management.
Operational Explanation
On-board incineration reduces the volume of solid waste and sludge, but is subject to precise restrictions on what may be incinerated, where, and how the resulting ash must be managed.
Before starting a cycle, connect the material and its origin with the permitted route and the unit’s type approval. Check local restrictions with the bridge, then follow the manual for preparation, feeding, monitoring and stopping. At completion, distinguish material actually incinerated from ashes still on board: GRB, ORB and supporting evidence must describe their respective operations, rather than a planned delivery.
Distinguish the incinerator from the machinery/boiler route
Annex VI regulation 16, in the 2021 revised text of MEPC.328(76), limits substances and equipment: except for the regulation 16.4 route, shipboard incineration takes place in an incinerator (16.1). Regulation 16.4 also permits the main or auxiliary power plant or boilers for sewage sludge and sludge oil generated during normal ship operation, but prohibits that route inside ports, harbours and estuaries.
That regulation 16.4 restriction concerns the machinery/boiler route; it does not establish a general MARPOL ban on using an approved incinerator in port. Actual operation still requires permitted materials and operating conditions, local rules and the provisions of regulation 16.5: the equipment name alone does not authorize starting it.
Check national and port restrictions as well. California CARB identifies an incineration prohibition for covered ships within three nautical miles of the California coast; check scope and exceptions under 17 CCR §93119. In Rotterdam, Port By-Laws 2020, July 2023 version, article 4.1(b) prohibits incinerator use in port. These examples refer to the cited sources: confirm current rules, jurisdiction and authority instructions for the actual call. The provisions referenced by regulation 16.5 also remain applicable.
Regulatory Reference
Annex VI, regulation 16 and Appendix IV: MEPC.328(76). Prohibited materials include Annex I/II/III cargo residues and contaminated packaging, PCBs, garbage with more than traces of heavy metals, refined petroleum products with halogen compounds, sewage sludge/sludge oil not generated on board, and EGCS residues. PVC is allowed only in an appropriately IMO type-approved incinerator (16.3), not simply because it is plastic.
For units subject to 16.6.1, continuously monitor combustion-chamber gas outlet temperature throughout operation (16.9). Continuous feeding of solid waste requires at least 850 °C at the outlet. MEPC.1/Circ.795/Rev.10, §15 distinguishes sludge oil from normal operations: it may be fed once the 650 °C chamber preheat temperature is reached, following the approved manual. For batch units, 600 °C within five minutes refers to the actual solid-waste combustion space: this is a design/test requirement, not an instruction to repeat a type-approval test on board using the outlet sensor.
Appendix IV and MEPC.244(66) set type-approval limits including 850–1,200 °C, O₂ 6–12%, average CO at most 200 mg/MJ, average soot Bacharach 3/Ringelman 1 and unburned ash components at most 10% by weight. Regulations 16.7–16.8 require the manual at the unit and trained operators. Do not alter interlocks or setpoints to reach a number quoted on this page.
Scope of Application
Regulation 16.6.1 covers incinerators on ships constructed on or after 1 January 2000 or installed on or after that date. Regulation 16.6.2 permits Administration waivers for specified pre-19 May 2005 installations on ships operating solely within waters under its sovereignty/jurisdiction. Check certificate date and standard: MEPC.244(66) does not automatically invalidate earlier valid approvals. MEPC.368(79) removes the fire-protection annex of the 2014 specification; it does not itself impose universal retrofit.
Procedure / How to Complete It
- Identify the material, its onboard origin and required approval; specifically check PVC.
- Check local restrictions and coordinate with the bridge. Burning normal-operation sewage sludge/sludge oil in machinery or boilers is prohibited in ports, harbours and estuaries (16.4).
- Follow the manual, interlocks and required training. For 16.6.1 units outlet-temperature monitoring is continuous, not periodic; distinguish solid waste from sludge-oil feeding.
- Record garbage incineration in the GRB with start/end dates, times and positions, categories and m³; record sludge in ORB Part I under the applicable C item. Additional logs apply only where required by the manual, SMS or authorities.
- Retain category E ashes and record delivery when it occurs: generation is not a completed delivery. Keep the receipt.
Practical Example
The Garbage Record Book form — Appendix II of Annex V, res. MEPC.201(62), now superseded by the form of res. MEPC.277(70) — asks for the estimated amount in cubic metres, not in kilograms; and for a delivery to a reception facility the position column carries the port or facility, not a position under way, which belongs to discharge-to-sea or incineration entries.
The correct entry separates two distinct operations, each on its own row. The incineration: start and stop dates and times, two positions of the ship — at the start and at the stop of incineration, category of waste burned, estimated amount in m³ in the Incineration column, signature. The landing of the resulting ash: date and time, port or facility — “Trieste, facility X” — category “Incinerator ashes”, estimated amount in m³ in the To Reception Facility or Ship column, signature, and the facility's receipt kept with the book.
Use the two-part MEPC.277(70) format: Part I A–I; Part II J/K for solid bulk cargo residues. Ashes are category E. Use unambiguous dates; do not present a date format as mandatory where Appendix II does not prescribe it.
What Typically Goes Wrong
Starting without checking local rules or feeding prohibited materials creates a compliance risk. PSC or enforcement consequences depend on the facts, not automatically on starting in port.
Common Mistakes Mistake Library
| Mistake | Consequence | How to avoid it |
|---|---|---|
| Banning PVC in every case or accepting it as generic plastic | The selected route may be inconsistent with the incinerator’s type approval | Check the appropriate IMO type approval for PVC and the manual’s limits; do not infer acceptability from the material alone |
| Accepting sewage sludge or sludge oil from another ship | The material does not meet the shipboard-origin requirement in regulation 16.2 | Verify origin and segregation before feeding; use only permitted materials and routes |
| Replacing continuous temperature monitoring with hourly readings | Changes during operation may be missed and applicable regulation 16.9 not met | For regulation 16.6.1 units monitor the outlet throughout operation; distinguish feeding thresholds from the design test under the manual and UI section 15 |
| Confusing ashes generated with ashes delivered | The GRB may attest a delivery that has not occurred and diverge from ashes retained | Record completed incineration and, separately, actual delivery of category E ashes with its own particulars and evidence |
Operating hours and ash quantities have no universal ratio.
What the PSCO Checks
A PSCO may check the applicable certificate, manual, training, operation and GRB/ORB records. Additional operational logs depend on relevant requirements; this does not create a universal separate log or fixed hours-to-ash conversion.
Operational Tips
- Set an internal procedure requiring bridge confirmation before start-up — not on the question “are we in port?”, but on the jurisdiction and the applicable local rules. Keep a list of the regular calls with each one's incineration rule on board: check that it is up to date before the call.
- Train the crew on the waste categories prohibited from incineration.
- For sludge oil use the Oil Record Book, not the Garbage Record Book as a substitute register: the documentary route must stay consistent with the material incinerated.
Preparation checklist
Educational checklist. This summary supports learning and preparation only. It does not replace the vessel’s approved procedures, manuals, statutory documents, company SMS, or applicable official requirements. Completing it demonstrates neither compliance nor readiness for an inspection: it shows that a list has been read, not that the ship is in order. Always verify the current documents carried on board.
- Approval, permitted materials and sludge origin checked
- Local rules and the regulation 16.4 machinery route checked
- Continuous temperature monitoring for 16.6.1 units and manual followed
- GRB and ORB completed by material and operation
- Ashes retained or delivered with receipt, without advance entries
FAQ
Related Topics
Certified substantive revision: 16 October 2026 · page fingerprint 7273b580359c