Overview
As of March 2026, a new ECA fuel zone has been introduced in IMOS: ECA – BOHAI SEA – SCRUBBER RESTRICTION.
This zone addresses the regulatory requirement that prohibits scrubber use within the Bohai Sea, which differs from the broader ECA – China zone where scrubbers remain permitted.
This article explains the background, how the new zone works, how to configure it, and how it interacts with the existing ECA – China fuel zone.
Background
The Bohai Sea is geographically nested within the broader ECA – China zone. However, unlike ECA – China, the Bohai Sea enforces a specific ban on open-loop scrubber discharge. Previously, when ECA – China and ECA – Bohai Sea were both active, ECA – China would take precedence, which meant scrubber-fitted vessels were incorrectly permitted to burn high-sulfur fuel (IFO) in an area where that is not allowed.
This led to inaccurate voyage calculations for operators running open-loop scrubber-fitted vessels in Chinese waters. The new ECA – BOHAI SEA – SCRUBBER RESTRICTION zone resolves this by allowing both zones to be active simultaneously, with the most specific zone taking precedence.
What Changed
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A new ECA zone, ECA – BOHAI SEA – SCRUBBER RESTRICTION, has been added to the Distances database.
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This zone can now be active simultaneously with ECA – CHINA, without one overriding the other.
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The zone is pre-configured with Closed Loop as the value in the Allowed Scrubbers field in the Ports List.
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The old ECA – BOHAI SEA fuel zone can now be marked Inactive if you are enabling the new Scrubber Restriction zone in your Fuel Zone setup.
How It Works
When a scrubber-fitted vessel enters the Bohai Sea ECA area, the system evaluates the zone settings independently from ECA – China. The behavior depends on the vessel's scrubber type:
|
Vessel Scrubber Type |
Behavior in ECA – Bohai Sea |
|---|---|
|
Closed Loop |
Scrubber use is permitted. Fuel zone settings follow the Scrubber tab. |
|
Open Loop |
Scrubber use is not permitted. The system automatically switches to the Non-Scrubber tab of the designated Fuel Zone setting. |
|
No Scrubber |
Standard low-sulfur fuel consumption applies. |
Example scenario (tested and confirmed): An open-loop scrubber-fitted vessel carrying IFO and MGO, travelling from Fancheng to Chingtang:
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Burns IFO while transiting ECA – China (scrubbers permitted).
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Switches to MGO upon entering ECA – Bohai Sea (scrubbers not permitted; system falls back to Non-Scrubber tab).
Setup Instructions
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Navigate to Data Center > Ports and Areas > Fuel Zones.
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Locate or create your Fuel Zone Set. Ensure CFGEnableScrubberType is enabled (this activates the Scrubber / Non-Scrubber tabs).
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Find the ECA – BOHAI SEA – SCRUBBER RESTRICTION zone in the list and configure:
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Scrubber tab: Enter the fuel types applicable for closed-loop scrubber vessels (e.g. IFO).
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Non-Scrubber tab: Enter the compliant low-sulfur fuel type (e.g. MGO).
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Confirm that Closed Loop is set as the Allowed Scrubbers value for Bohai Sea ports in the Ports List.
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If you have previously been using the old ECA – BOHAI SEA zone, you may now mark it as Inactive to avoid duplication.
Note: Do not deactivate ECA – CHINA. Both zones need to remain active to ensure correct simultaneous evaluation.