Module 10 - Scenario Simulator
Scenario Families
What you will learn
Classify routine, safety, urgency and distress situations from risk and required action before selecting a signal.
Priority is a judgement about the present situation. Memorised keywords can mislead when conditions change.
Routine traffic covers ordinary operational business without a safety, urgency or distress priority. Safety traffic communicates an important navigational or meteorological warning. Urgency concerns the safety of a person, vessel or other vehicle without the grave-and-imminent-danger condition of distress. Distress means grave and imminent danger requiring immediate assistance.
Classify from the current facts, then choose the corresponding procedure. A failed engine in open water may be routine assistance, urgency or distress depending on drift, sea room, weather, crew and how quickly danger is developing. The words 'engine failure' alone do not assign the priority.
Reassess throughout the exchange. A medical urgency can become distress if the casualty or vessel enters grave and imminent danger. Conversely, do not downgrade a genuine distress to avoid embarrassment. State the operational change that justifies changing priority.
| Family | Decision boundary | Example action |
|---|---|---|
| Routine | Ordinary operational request | Call, move to a suitable working channel, exchange information |
| Safety | Important navigation or weather warning | Use the safety procedure and broadcast relevant facts |
| Urgency | Serious concern for safety, not yet distress | Use Pan-Pan and request advice or assistance |
| Distress | Grave and imminent danger requiring immediate assistance | Use the distress alert/call/message appropriate to the equipment and situation |
Classify from consequences, not nouns
A yacht's engine stops. It remains under sail in safe water, but later loses steerage and begins drifting onto rocks in breaking seas.
1. Initial state
An engine fault alone does not establish distress while the yacht remains safely controlled.
2. Changed risk
Loss of control, close rocks and breaking seas create grave and imminent danger.
3. Escalate
Change to the distress procedure and communicate the current position, danger and assistance required.
Sense check: The equipment fault did not change; the risk did. Priority follows the risk.
Common mistake or limitation
- Using Mayday for every mechanical fault.
- Treating safety and urgency as interchangeable because neither is routine.
- Keeping the initial priority after the operational risk has materially changed.
Recap
- Distress requires grave and imminent danger and immediate assistance.
- Urgency is serious without that distress threshold; safety concerns warnings.
- Reclassify when the facts and consequences change.
Optional quick check
Section 7 of 8
What determines whether an engine failure is routine, urgency or distress?
Sources and factual review
Reviewed 20 August 2026 - Compass Revision editorial review.
Continue studying Scenario Simulator
This public lesson is part of Revision Module 10. Full revision access adds the guided Learn, Practise and Test flow, flashcards and revision progress.