Can cargo holds be cleaned during the voyage? Cleaning at sea and at anchorage before the load port

Can holds be cleaned during a voyage?

Yes. Cleaning on the ballast passage between discharge and load ports is standard practice on bulk carriers, whether by ship's crew or a riding crew. Most of the work (sweeping, washing, chemical cleaning, rinsing and drying) can be done at sea, subject to:

• MARPOL Annex V rules on discharging residues and wash water
• Weather and sea state
• Safety: atmosphere testing, enclosed space procedures, working at height in a moving ship
• Hatch cover operation at sea, which only happens when the Master agrees it's safe

What MARPOL allows at sea

MARPOL Annex V sets the conditions for discharging cargo residues and hold wash water at sea. Based on P&I club guidance (Skuld, Britannia):

• Residues and wash water of cargoes not classified as harmful to the marine environment (non-HME), and cleaning agents that are not harmful, may be discharged:
  • while the ship is en route
  • at least 12 nautical miles from the nearest land (or ice shelf)
  • outside special areas, unless all the conditions in regulation 6.2 are met
• HME residues must not be discharged at sea. Wash water containing them has to be retained and delivered to a port reception facility.
• Discharges must be recorded in the Garbage Record Book.

The Annex V special areas are the Mediterranean, Baltic, Black Sea, Red Sea, the "Gulfs" area, the North Sea, the Antarctic area and the Wider Caribbean region. If your passage runs through one of these, plan the wash for the parts of the route outside it, or retain the wash water.

This is the single biggest planning constraint for cleaning on passage. Check whether the previous cargo is HME (the shipper must declare it), check the route, and plan washing windows accordingly. We cover the details in a separate guide to MARPOL and hold wash water.

Can cargo holds be cleaned at anchorage?

Often, yes, but rules vary by port. At anchorage you're within 12 nautical miles of land almost by definition, so you generally can't discharge wash water overboard. Many ports allow:

• Sweeping and residue removal, with residue landed ashore or retained
• Washing with wash water retained on board (in a hold, tank or bilge holding tank approved for the purpose) for later discharge where permitted

Some ports don't allow any washing at anchorage, and some require permits. Always ask the agent before you start, and keep the response in writing.

Weather: the factor everyone underestimates

A five-day passage isn't five days of cleaning. Plan for:

• Rolling and pitching that makes work at height unsafe
• Spray and rain that stops hatch covers being opened for drying
• Heat that dries chemical on the steel before it can be washed off
• Humidity that stops holds drying

If you're crossing a monsoon area or winter weather, assume fewer working days and plan more people, not more days.

How to prepare holds before arriving at the loading port

Here's a typical plan for cleaning en route:

1. Before sailing from the discharge port: remove as much residue as possible, clean hatch covers and coamings, clear the bilge wells. Get sweepings ashore if you can. Load chemicals and fresh water.
2. First day at sea: test the atmosphere, ventilate, start rough washing in the first hold once the ship is clear of land and outside any special area (for non-HME residues).
3. Middle of the passage: chemical cleaning and HP washing, hold by hold. Rope access or a riding crew works the upper structure.
4. Last part of the passage: fresh water rinse, then drying with hatches open if weather allows and mechanical ventilation if available.
5. Before arrival: Chief Officer's pre-inspection, bilge wells prepared, photographs taken. Report hold condition to the charterer and agent.

Why cleaning at sea saves money

The value of cleaning at sea is the port days you don't spend cleaning. Every day at anchor doing work that could have been done on passage is a day of hire, plus the risk of missing the laycan. That's why operators increasingly plan cleaning at sea from the moment a fixture is agreed. If the crew can't do it all in the time, a riding crew can, and the guide on how long hold cleaning takes helps estimate whether they'll need help.

Safety at sea

• Test the hold atmosphere before every entry and keep monitoring.
• Follow the ship's enclosed space entry and permit-to-work procedures.
• Don't work at height in heavy weather.
• Keep hatch covers secured when not in use, with extra securing if open at sea.
• Brief everyone on emergency procedures and muster stations.