Recommissioning of vessels following lay-up – what you need to know

Recommissioning of vessels following lay-up – what you need to know


Recommissioning of vessels following lay-up – what you need to know

Many vessels have been decommissioned for long periods due to the global COVID-19 pandemic and there are a number of risk management steps that should be considered to minimise potential issues when re-commencing vessel operations.

AlphaXO Risk Partners and Greg Lambert, a maritime engineer and Managing Director of Hillgrove Industries, have put together a simple guide for shipowners and operators to help with the recommissioning of vessels following lay-up. The checklist is broad and ranges from documentation and machinery through to safety and hygiene factors.

It is important to follow a robust and structured process when re-commissioning vessels as this will help manage the risk of machinery breakdown/failure and regulatory breaches at precisely the time when there is an opportunity to earn income again from the vessel.

Administration & Training

Prior to vessels re-commencing operations, you must remember to ensure that all your documentation is up to date.

That includes Certificate of Operation, Certificate of Survey, Registration Certificate, fire-fighting equipment certificates, ship station apparatus license, liquor license and not to mention crewing certificates of competency.

Most importantly, if you are currently insured on a laid-up basis, don’t forget to notify your insurers in good time of your intended return to operational status and be prepared to act upon any specific requirements they may have. Most P&I Clubs have a Reactivation Clause within the insuring conditions/rules that requires the shipowner to give prior notification, so that consideration can be given to a condition survey.

It is also a good time to refresh and remind everyone of emergency procedures, including drills for man overboard, fire, flood, collision, piracy, terrorist attack etc. In doing these drills, not only are you meeting statutory requirements, you are also testing the systems to ensure that everything is operating correctly and at its rated capacity.

Successful emergency management is all about preparedness and familiarity with the procedures and equipment.

Engines, Gearboxes, Drivelines, Stainless Steel Components

Following any extended laid-up period there are various areas to check, clean, maintain and prepare for re-entry to normal service.

When an engine is sitting idle, various fluids stagnate and they can change dramatically in their chemical and pH composition as reactions occur in the fluids and the surrounding pipework.

Bacteria in salt water, for example, consume the available oxygen in the water leaving it oxygen depleted. This in turn can cause issues for stainless steel in contact with such oxygen depleted fluid. Stainless steel (propeller shafts, bolts, rigging etc.) is also susceptible to other forms of damaging corrosion such as crevice corrosion which may go unseen to the naked eye. However, there are typical tell-tale signs to look for such a “tea staining” or isolated “rust spots”.

The thin oil coatings on engine internals are further depleted leaving exposure for potential rust and excessive wear on startup prior to an oil wedge being formed in operation. Pre-lube pumps are a good way to minimise such wear or routinely run the engines during lay-up for a short period.


Fuels are susceptible to aerobic and anaerobic bacterial and fungal growth (“microbial growth”) particularly at the interface layer between the fuel (all fuels including diesel and petrol) and any water in the tank. Water may have come through poorly sealed deck fittings or as easily as condensation in a tank as the temperatures and dew points change. Various anti-bacterial additives are available to help minimise bacterial growth in fuels for storage and general day-to-day use.

Pumps and seals

During extended shutdown periods, pumps will suffer from similar problems associated with rust and corrosion as other items of machinery. Internally, there will be development of rust, corrosion and general degradation of internal parts which may remain unseen until pump failure.

For example, rotating mechanical seals often grab on the faces and when the pump is reactivated can tear or damage, resulting in immediate seal failure.

Similarly, lip seals and wiper seals can also become brittle over time, sticking to shafts or surfaces during periods of longer storage (without lubrication), then tearing when recommissioned.

Hatches and seals

Similar to pumps and machinery seals, hatches (both rotating and stationary), scuttles, portholes etc may suffer from lack of use. During extended times of no use, seals can stick, degrade and suffer UV attack.

Toilets, basins, sinks and tanks

During periods of no use, black water systems can suffer from many issues such as evaporation, insufficient bacteria, or lack of input water.

S-bends and pot belly traps may no longer have the sealing plug of water, thus potentially allowing noxious poisonous gasses (e.g. H2S) to permeate from the tank to areas in which crew or passengers congregate.

Pipework and tanks which have dried out may have crystalline deposits (solids) obstructing water flow during re-activation. Such solids need to be mechanically removed or dissolved with appropriate chemical treatments.

Certain black water processing systems rely on regular inputs to maintain their operational capacity. After long idle periods, such systems need to be “restarted” with fresh loading and starter bacteria – much like the yeast for a sourdough loaf!

Safety equipment

During the period of lay-up, items such as EPIRB’s, inflatable lifejackets, flares, torch batteries and so on continue their unstoppable pathway towards expiry / replacement dates, which all too often creep up and surprise you.

General aesthetics/corrosion/marine growth

All the normal environmental wear and tear aspects do not cease when a vessel is laid-up and not operating. Indeed, a laid-up vessel is far more susceptible to rapid marine growth than a vessel in regular operation.

The same can be said for sea water intakes becoming overgrown with marine growth, then leading to overheated engines or lack of fire-fighting capacity etc. when the vessel is reactivated. It would be prudent to send in divers to check over the underwater section of the hull, running gear and all intakes, clean them and make ready for use.

Batteries and electrical

Just because a vessel is laid-up does not mean that maintenance stops. The likes of battery systems, especially wet lead acid batteries, require regular (weekly) maintenance, testing and checking. Even other battery technologies require maintenance including checking terminals for tightness and corrosion along with maintaining an appropriate state of charge for the battery technology.

These days, many vessels are fitted with solar panels which over time can become less efficient due to fouling, either from atmospheric dirt deposits or bird fouling. A simple clean and proper washdown can restore their capacity and efficiency.

Similarly, solar panels and controllers (MPPT & PWM) need to be setup correctly to ensure that battery systems are not overcharged during times of little use, leaving them to provide a maintenance float charge.

During extended lay-up periods, you may be less likely to monitor the condition of your electrical systems, AC and DC leakages and decoupling. You are most likely to remain connected to shore power for the extended period, which can also add to electrically driven damages, some often very rapid, in the case of stray current and the resulting electrolysis.

Mooring systems

While a vessel is laid-up, the UV attack on all exterior surfaces, ropes, rigging etc. continues. Given that mooring lines may not have been used for many months, they should be inspected and replaced if necessary. Whilst this is, of course, a normal maintenance item, having been laid-up, it is highly likely they have not been checked as regularly as when the vessel is in and out of the berth every day with crew handling the mooring lines.

We wish everyone a successful recommissioning, safe return to service and a profitable operation.

If you have any questions then please contact us

T:1300 066 391
Outside AU: +61 2 8236 8600