PACE: The Escalation Framework Behind 'Challenge and Response'

Where 'Challenge and Response' Actually Comes From

Bridge Resource Management training talks a lot about "challenge and response culture," but the phrase alone doesn't tell you how to actually do it in the moment — especially when the person you'd be challenging outranks you. PACE is the concrete tool underneath it: Probe, Alert, Challenge, Emergency, a graded assertiveness model originally developed in the medical field to help nurses raise concerns with doctors, adopted into aviation and maritime BRM for exactly the same power-dynamic problem.

The Four Levels — With the Actual Language

• PROBE — "Do you know that...?" A low-cost, non-confrontational opener. If you're wrong, no harm done; if you're right, it's often enough on its own.
• ALERT — "Can we re-assess the situation...?" A step up — you're now naming that something needs a second look, not just offering information.
• CHALLENGE — "Please stop what you are doing while..." This is a direct intervention, not a question. It's meant to feel uncomfortable — that's the point of a graded model, it should only reach this level when a probe and an alert haven't resolved the risk.
• EMERGENCY — "STOP what you are doing!" The final level, used when there's no time left for discussion.

Starting at Probe matters as much as knowing Challenge and Emergency exist — beginning with the lowest-cost intervention is what makes escalating to the higher ones defensible and less personally costly when they're genuinely needed.

Where This Sits in ISM and the ICS Bridge Procedures Guide

The ICS Bridge Procedures Guide (BPG, now in its 6th edition, January 2022) is the industry-standard reference most ships' bridge procedures manuals are built around — and its authors were explicit in the latest edition that a challenge and response approach "should not under any circumstances be considered undermining the authority delegated to the OOW by the Master." That line exists because the biggest real barrier to using PACE isn't not knowing the framework — it's the fear that using it damages your standing with a senior officer or a pilot. The BPG ties this directly to the ISM Code's concept of continuous improvement and the watchkeeping requirements of STCW Chapter VIII — challenge and response isn't a soft-skills add-on, it's built into the same regulatory framework as your Safety Management System.

What This Means for You

• Practice starting at Probe — it's the cheapest intervention and the one people skip because it feels unnecessary. It's also the one that prevents most situations from ever needing Challenge or Emergency.
• If a Probe or Alert gets reassurance that doesn't actually address the risk, that's the signal to escalate — not a reason to stop
• This applies upward against a Master exactly as much as it applies against a pilot. Rank changes how hard it feels, not whether it's justified.
• If you're the one being challenged — Master or pilot — the correct response per the BPG is to treat it as the system working, not as a challenge to your authority

Test Yourself

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Related Reading

• Ali Ka — Challenging the Pilot, River Thames (Decision Simulator)
• Ruyter — When It's the Master You Need to Challenge (Decision Simulator)