When Should the Officer on Watch Summon the Ship's Master?

On a commercial vessel, whether that’s a cargo ship or a cruise ship, the Officer of the Watch (OOW) carries significant responsibility. During their watch, they handle the safe navigation of the ship, maintaining situational awareness, and ensuring that the vessel follows international regulations and the company’s procedures.  

However, the OOW doesn’t work alone in decision-making and one of the most important professional judgments they must make is knowing when to call the Master – which is how the ship’s Captain is usually referred to on commercial ships. 

International regulations, company standing orders, and good seamanship all emphasize that the OOW should never hesitate to summon the Master whenever a situation creates uncertainty or could affect the safety of the vessel, crew, cargo, or environment.  

The Master ultimately holds command responsibility, and early communication allows decisions to be made with his or her full awareness of the circumstances. 

In this blog post, Martide explores the main situations in which an Officer of the Watch should call the Master, why it matters, and what risks arise when the call is delayed or – worse - never made. 

But first: 

What are Officer of the Watch (OOW) Jobs at Sea? 

An Officer of the Watch is responsible for the safe navigation and operation of a vessel during their assigned watch on the bridge. Their duties include monitoring the ship’s position and course, maintaining a proper lookout, managing bridge equipment, and ensuring compliance with maritime regulations.  

The OOW must remain alert to traffic, weather, and navigational hazards while making timely decisions to keep the vessel, crew, cargo, and environment safe. 

The Importance of Calling the Ship’s Master

Calling the Master is not a sign of weakness or lack of competence. In fact, it’s a fundamental part of safe bridge management – after all, modern shipping relies on teamwork and clear communication. The Master expects to be called when certain conditions arise, and most Masters include specific instructions in their night orders or standing orders on what the OOW should do in the event of an emergency or uncertainty.  

The key principle is simple: if the Officer of the Watch has any doubt about the safety of the ship or what the correct course of action to take is, the Master should be called at once, regardless of whether they’re on their break or fast asleep in their cabin. 

Read more: How to Take Over a Navigational Watch 

Failing to do so can lead to accidents such as collisions, groundings, machinery damage, or environmental incidents. In many maritime accident investigations, a common finding is that the OOW hesitated to call the Master early enough.

Why Might the Ship’s Master Not be on the Bridge? 

The Master can’t physically be on the bridge - the vessel’s navigational command center - at all times because ships operate continuously, often 24 hours a day. Therefore, bridge duties are shared among qualified officers through a watchkeeping system.  

During routine navigation, the Officer of the Watch is responsible for the safe operation of the vessel while the Master remains available to be called whenever required. 

Ship’s Masters need their beauty sleep too!  

Reasons for Calling the Master of the Ship

Let’s take a look at some of the situations in which the Officer of the Watch would be correct in summoning the ship’s Master. 

Reduced Visibility 

One of the most common reasons to call for the Master is reduced visibility. 

Situations include: 

• Fog 
• Heavy rain 
• Snow 
• Sandstorms 
• Smoke or haze 

Reduced visibility significantly increases the risk of collision. Radar and AIS provide useful information, but they cannot fully replace visual navigation. If visibility drops to a level where navigation becomes uncertain or traffic becomes difficult to monitor, the Master should be called. 

The Master may decide to reduce speed, alter the bridge manning level, or take direct control of the navigation. 

If the OOW delays informing the Master, the vessel may find itself too close to other ships or hazards before effective action can be taken. 

Heavy Traffic 

Busy shipping lanes, port approaches, and narrow channels often create complex traffic situations. 

Examples include: 

• Traffic separation schemes 
• Congested port approaches 
• Fishing fleets 
• Vessels crossing the ship’s track 
• Unpredictable vessel behavior 

When the traffic situation becomes difficult to manage safely, the OOW should call the Master. 

The Master’s experience can help evaluate risk and coordinate maneuvering decisions. Calling early allows the Master to observe the situation before it becomes critical. 

If the OOW tries to handle complex traffic alone, the risk of misjudgment increases, particularly at night or in poor weather. 

Approaching Land or Navigational Hazards 

Another key situation requiring the Master’s presence is when the ship is approaching: 

• Coastal waters 
• Narrow channels 
• Shoal areas 
• Traffic separation schemes 
• Pilot boarding areas 

Navigation in restricted waters leaves very little margin for error. Small deviations from the planned track can lead to grounding or collision. 

Company procedures usually require the Master to be on the bridge for such operations, but the OOW should always call the Master well in advance if there is any doubt about the situation. 

Failure to call the Master during critical navigational phases has been a contributing factor in many grounding incidents. 

Unexpected Changes in Weather 

The weather can deteriorate rapidly at sea. Strong winds, heavy seas, or storms can affect the vessel’s stability, course keeping, and overall safety. 

The Master should be called when: 

• Wind or sea conditions become severe 
• Visibility is suddenly reduced 
• The vessel experiences heavy rolling or pitching 
• Cargo safety may be affected 
• Speed or course adjustments may be necessary 

The Master may need to evaluate whether the vessel should alter course, reduce speed, or take additional precautions. 

Read more: How Do Cargo & Container Ships Handle Rough Seas? 

If the OOW delays informing the Master, cargo damage or structural stress may occur before corrective action is taken. 

Equipment or Machinery Failure 

Bridge equipment failures can quickly create a dangerous situation. 

Examples include: 

• Radar malfunction 
• Gyro compass failure 
• Steering gear problems 
• GPS failure 
• ECDIS malfunction 
• Engine problems 

Even if backup systems are available, the Master should be informed at once. 

Modern navigation relies heavily on electronic equipment. When key systems fail, situational awareness may be reduced, and the Master may decide to increase bridge staffing or adjust the voyage plan. 

Ignoring equipment problems or trying to manage them alone can lead to loss of control or navigational errors. 

Risk of Collision or Close-Quarter Situations 

Whenever the risk of collision becomes significant, the Master should be called without hesitation. 

Warning signs include: 

• Another vessel not responding to VHF calls 
• Unclear intentions of nearby ships 
• Crossing situations becoming dangerous 
• Closest point of approach decreasing rapidly 
• Conflicting maneuvers in congested waters 

The Master may decide to take control of the navigation or provide guidance on the safest maneuver. 

If the Officer of the Watch delays calling the Master, a close-quarters situation can escalate into a collision before effective action is taken. 

Problems With Crew or Safety 

Operational issues onboard may also require the Master’s involvement. 

Examples include: 

• Crew injury or medical emergency 
• Security concerns 
• Fire alarms 
• Safety system failures 
• Suspicious vessels or piracy threats 

The Master must be informed immediately because these situations may require coordinated emergency responses. 

Failing to call the Master promptly could delay life-saving decisions. 

Doubt or Uncertainty 

Perhaps the most important rule of all is this: if the OOW feels uncertain about any situation, the Master should be called. 

Uncertainty can arise from: 

• Conflicting navigational information 
• Unclear radar contacts 
• Unexpected vessel movements 
• Unfamiliar waters 
• Equipment readings that don’t make sense 

Good seamanship encourages caution and calling the Master early prevents small uncertainties from becoming serious incidents. 

What Could Happen if the Master isn’t Called? 

When the OOW fails to summon the Master in time, the consequences can be severe. 

Possible outcomes include: 

• Collisions 
• Groundings 
• Environmental pollution 
• Cargo damage 
• Loss of life 
• Legal consequences for officers and company 

Maritime accident investigations frequently highlight the failure to call the Master as a critical factor and in many cases, the OOW waited too long because they believed they could resolve the situation alone. 

Final Thoughts 

The role of the Officer of the Watch is demanding and requires constant vigilance. Knowing when to call the Master is one of the most important professional skills a watchkeeping officer can develop. 

Read more: 6 Wellness Tips for Officers of the Watch 

The safest approach is simple: when in doubt, call the Master. 

Early communication ensures that decisions are made with the benefit of experience and command authority. Quick and decisive action also protects the vessel, the crew, the cargo, and the marine environment. 

In the end, no Master will ever criticize an officer for calling too early. But many accidents have occurred because the call came too late.