Adaptation as part of daily operations

LESSONS LEARNED: A recently published investigation report sheds light on the risk potential associated with adaptations under ordinary circumstances.

This learning emphasises the importance of ensuring that system design aligns with actual use. It also addresses how to identify necessary adaptations on board, assess whether they introduce new hazards and establish measures to account for and disseminate knowledge about these adaptations.

Practical solutions in steam system operation

In 2024, two crew members on board a Dutch cruise ship died when an expansion joint in a steam pipe burst. The rupture was traced to parts of the steam system that had remained isolated for six days following a repair. This lead to condensate accumulation where pressure changes caused a steam hammer, ultimately resulting in the failure of an expansion joint.

The engine room where the two crew members were located was filled with steam exceeding 100°C within 86 seconds. When inhaling steam, the functionality of the lungs is impaired, and in this case the consequences were fatal.

The investigation revealed a discrepancy between the system's design and its actual use. A practical workaround had been implemented: because the steam system was designed for continuous operation but was rarely used, two valves to the steam heater were kept partially open at all times.

Consequently, even when the system was not in use, it was never fully shut down. This condition was not considered in the original design nor in subsequent modifications.

The crew knew that the partially open valves would prevent cooling of the steam pipe, but not that it would help prevent the risk of condensation build-up and thus the risk of steam hammer. The crew as a whole did not know the necessity of keeping the valves open, nor the risks of not doing so.

On the basis of existing procedures, risk analyses and training materials, it was assumed that the risk of condensation build-up and the risk of steam hammer were only present in the start-up of the steam system (or parts of it).

The adaptation, or circumvention of the design in actual use, entailed a risk of condensation build-up and a risk of a steam hammer, because a valve could easily be shut off in the event of a fault – as was the case with the incident on board the cruise ship.

Why did it happen?

Work procedures, risk analyses and training materials do not always fully reflect the realities on board. It is impossible to predict all events that may occur.

As a result of this unpredictability, discrepancies can arise between how a system is designed and how it is actually used under normal operating conditions. Under ideal circumstances, procedures, risk analyses, and training should equip the crew to maintain safety under all foreseeable conditions.

However, this incident serves as a reminder that this is not always the case.

It is common for mismatches between design and practice to lead to practical solutions, where work is adapted to ensure tasks can be completed. Often, experience-based adaptations in the face of unforeseen situations will be a prerequisite for things to go well.

Nevertheless, it becomes problematic when daily work depends on adaptations to maintain safety. Adaptations often rely on tacit knowledge and experience – information that is not documented. Consequently, not everyone will necessarily have the same understanding of why one approach os chosen over another. The result can be uncertainty and thus the risk of error, even when people act according to existing procedures. There is also no clear overview of how an adaptation in one part of a system might affect functions in other parts of the system.

What can we do?

After the incident, it has been recommended to avoid using adaptations and workarouns in daily work on board. It is important to focus on how practice differs from theory and design.

Here are some suggested measures to help avoid adaptations:

• Talk to the crew to gain insight into whether there are any tasks that cannot be carried out as intended without adjustments.
  
  
• If adaptations are discovered, assessm whether they compromise safety on board or if they represent good and efficient work practices that could be shared.
  
  
• Consider the need for structural measures to prevent the need for adaptations. This may include necessary modifications, purchasing new tools, more crew or other measures that make it easier to work safely.

How to translate adaptations into known information?

It is common and natural for adjustments to take place on board in the daily work. Usually, the crew has a lot of knowledge and experience that is not written down in the procedures or training materials. The sum of this knowledge and experience enables them to perform their tasks safely ans quickly when procedures and systems fail. In these cases, adaptations are often a prerequisite for creating and maintaining safety on board.

When working to prevent adaptations during daily operations, it is therefore important to be open to understanding how and why adaptations occur and are used. There are many lessons to be learned from how seafarers use their experience and knowledge to close the gap between design and practice.