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Glossary
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Glossary
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Glossary — U
7 terms starting with U.
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Ultra Large Container Vessel
(ULCV)
Container ships >= 14,500 TEU — too large for the new Panama locks; restricted to Asia-Europe and Asia-East-coast-US-via-Suez routes.
Ultra Low Sulphur Fuel Oil
(ULSFO)
Residual marine fuel with ≤ 0.10% sulphur, used to meet Emission Control Area limits.
Ultrasonic Thickness Measurement
(UTM)
Non-destructive ultrasonic gauging of plate thickness to monitor wastage; required at intermediate / renewal class surveys.
Unattended Machinery Space
(UMS)
A classification notation permitting the engine room to operate without a watchkeeper at night, subject to enhanced alarms and automation.
United Kingdom Maritime Trade Operations
(UKMTO)
Royal Navy office in Dubai serving as the primary point of contact for merchant vessels in the Indian Ocean / Gulf high-risk areas.
United Nations Convention on the Law of the Sea
(UNCLOS)
The international treaty defining rights and responsibilities of nations in their use of the world's oceans, including maritime zones.
Unmanned Machinery Space
(UMS)
Engine room operated without engineer watch present, relying on automation, alarms, and a duty engineer on call.