When delays become damage: Cargo risks during prolonged voyages

Trade routes are shifting. So are cargo risks.

Recent events in the Middle East have renewed concerns about shipping routes through the region, forcing some vessels onto longer routes or to sit idle, extending transit times.

While much of the attention has focused on rising transportation costs, there is another consequence traders, charterers, shipowners and insurers should be watching closely: the impact extended voyages can have on cargo quality, safety and financial loss.

As organisations evaluate the potential impacts of disruption in the region, understanding the potential consequences to cargo quality is an increasingly important part of managing supply chain risk. 

Why longer voyages matter

For many bulk liquid cargoes, time in transit is a critical risk factor.

Cargoes such as crude oil, refined fuels, chemicals and edible oils are typically transported under specific handling conditions designed to preserve cargo quality and ensure onboard safety. When voyages take longer than expected, those products remain on vessels longer than intended, increasing the likelihood of quality deterioration or other cargo-related issues.

In some cases, the effects may be relatively minor. In others, delays can create operational challenges, quality concerns or safety risks that may ultimately result in claims and financial loss, or in the worst-case scenario, may imperil the safety of the vessel and crew.

The cargoes that face the greatest risk

The risks associated with extended carriage vary depending on the cargo being transported. 

Some products are more vulnerable to delays than others:

• Crude oil and dirty petroleum products (DPP) can precipitate waxes, sediments or sludge during prolonged storage, leading to pumping or handling issues and potential shortages on discharge.
• Clean petroleum products (CPP) such as gasoil, jet fuel and gasoline may undergo oxidation, leading to gum formation and a deterioration in cargo quality. Microbial growth can also occur when free water is present in these cargoes.
• Chemical cargoes can damage cargo tank coatings when carried for longer than recommended by the coating manufacturers, even if the cargo is compatible with the coating system over shorter-term carriages. There may also be an increased risk of corrosion with certain cargoes within stainless steel cargo tanks that would otherwise not be an issue with shorter voyages.
• Polymerising chemical and liquid gas cargoes, including styrene, butadiene and other monomers, require cargo tank atmospheric control, ongoing monitoring and inhibitor management to prevent instability. These cargoes present the highest risk to the safety of the vessel and crew with longer carriages due to the risk of runaway polymerisation. 
• Edible oils and fats will naturally and inevitably oxidise and degrade over time, forming free fatty acids that may increase to concentrations above the maximum specification limit. 
• Liquefied gas and high vapour pressure cargoes may be more susceptible to evaporative losses during extended voyages and consequent shortage claims.

The specific risks depend on the cargo, voyage duration and storage conditions, making cargo-specific planning and monitoring particularly critical during periods of disruption.

The importance of monitoring and documentation

The longer a cargo remains at sea, the more important it becomes to understand its condition, and whether quality and safety have been compromised.

Regular sampling, testing and condition checks can help cargo interests, charterers and shipowners identify developing issues early and, where possible, take steps to reduce further deterioration or to minimise safety risks. However, in some cases, quality deterioration is inevitable due to the inherent nature of the cargo. 

For certain crude oils and petroleum products, operators can maintain recommended carriage temperatures and recirculate cargo to help reduce the precipitation of waxes, sediments and sludge. Cargoes vulnerable to oxidation may require nitrogen blanketing or inert tank atmospheres, where practicable and when in line with charterer’s or industry standard carriage recommendations. For some cargoes, even this step will not prevent oxidation and quality deterioration. 

Regular cargo sampling and analysis can be performed to track changing cargo quality specifications over long-term carriages. Visual assessment of cargo samples can also help identify microbial growth when free water is present in petroleum products, meaning microbial contamination can potentially be treated prior to proliferation of microbial growth.

Thorough documentation of any issues will also assist should a dispute over cargo quality occur during the voyage or following delivery. Recording cargo carriage conditions (such as temperature and tank atmosphere), test results and actions undertaken throughout the voyage can assist in understanding how cargo quality changed over time and to support future claims, if necessary. 

Retaining and documenting cargo samples, taken either unilaterally or jointly, can also provide valuable evidence if questions arise later about the cargo’s condition.

Preparing for uncertainty

As uncertainty continues to affect global shipping routes and voyage schedules, cargo owners should look beyond the risk of delayed deliveries.

While supply chain disruptions often focus attention on schedules and costs, prolonged voyages can also affect cargo quality, create safety concerns and increase financial exposure.

Understanding these risks, and planning for them before a loss occurs, can put organisations in a stronger position to navigate ongoing disruption and its potential impacts.

When cargo damage or deterioration occurs, Sedgwick’s marine specialists help clients determine the cause, assess the extent of potential loss, provide specialist technical advice and navigate complex cargo claims with confidence.

Looking for a deeper dive? Watch for our upcoming commentary paper, where we’ll take a closer look at how prolonged voyages can affect cargo quality, safety and claims exposure.