In a recent discussion with the IMRF, Dr Paddy Morgan, Medical Director for HM Coastguard, outlined a new triage guideline to support search and rescue (SAR) crews during mass rescue operations (MROs). The Multiple Persons in Water Triage Tool is grounded in operational experience and helps responders make faster, consistent, and survival evidence based decisions when time is critical.

The Multiple Persons in Water Triage Tool focuses on rapid assessment and prioritisation in resource-constrained environments.

“This grew out of a need identified during rescues,” Paddy explained. “People often ask themselves, ‘Did I make the right call?’ This tool provides clearer, defensible triage guidance for responders when they have to act under pressure.”

Developed with input from maritime SAR professionals and medical specialists, the tool is intended for situations where the number of people in the water exceeds available resources to rescue them. In these circumstances, crews must make difficult decisions quickly. The guideline offers a structured way to prioritise casualties based on their likelihood of survival.

A tool shaped by real conditions

MROs vary widely, and what is considered an MRO can differ depending on the setting.

The International Maritime Organization (IMO) defines an MRO as ‘characterised by the need for immediate response to large numbers of persons in distress, such that the capabilities normally available to search and rescue authorities are inadequate’.

These incidents are complex and large in scale, but relatively rare. As a result, most SAR organisations have limited direct experience in responding to them. Despite this, they can occur anywhere, at any time, and often carry serious consequences.

“In any triage situation, you are trying to have the greatest impact for the greatest number of people, as quickly as possible,” said Paddy. “At sea, that means identifying who is most at risk of dying first.”

In practice, this is rarely straightforward. People in the water are constantly moving. Conditions change quickly. Rescuers often undertake triage from the elevated position of a helicopter or deck of a lifeboat. Committing to rescue and resuscitate one casualty can mean others are missed who would otherwise survive.

The tool focuses on three key observations:

• Airway: is the casualty’s mouth and nose above the water
• Flotation: do they have effective buoyancy
• Movement: are they actively trying to stay afloat or reach safety

These indicators support rapid assessment, and can be performed without contact with the casualty. Those able to stay afloat or move towards safety are lower priority. Those without flotation, or struggling to keep their airway clear, are higher priority. Anyone recently submerged and still moving, or close to submerging, is the most urgent.

At the centre of this approach is the risk of hypoxia (inadequate amount of oxygen in the body).

“If the airway [mouth and nose] is below the water, lack of oxygen will kill in minutes,” Paddy said. “Cold water matters, but lack of oxygen is the immediate threat.”

Supporting decisions under pressure

The tool is designed not only to improve outcomes, but also to support decision-making in high-pressure environments.

It does not require rescuers to declare a casualty dead. Instead, it helps identify when someone is no longer breathing and when survival is unlikely without prolonged interventions. In an MRO, committing resources to one casualty may mean losing others with a greater chance of survival.

A clear framework reduces uncertainty. It supports consistent decisions and makes those decisions easier to explain afterwards.

Flexible, scalable and looking ahead

The tool is flexible. It can be applied when rescue demand exceeds capacity and stepped back as the situation stabilises. Those leading the response retain discretion to adapt it to the conditions on scene.

Because it relies on simple visual assessment, it is accessible to a wide range of organisations, from low-resource services to highly equipped SAR units.

“It’s about recognising a few key signs,” Paddy said. “If you can do that, you can use it.”

Emerging technologies, including drones and artificial intelligence, may further strengthen its application. They could support casualty detection, track movement, and enable continuous reassessment as incidents evolve.

“Time is the enemy,” Paddy said. “The sea is always moving, but it is the time without oxygen that matters most.”

As Paddy put it, the aim is simple. Help rescuers make better decisions in the moment and, where possible, save more lives.

The IMRF, through its MRO resources, including the Mass Rescue Operations Guidance, which is the most comprehensive guidance available. This guidance outlines the critical components of an MRO response: the need for additional resources, enhanced coordination, specific planning, dedicated training and exercises, and learning from real-world incidents. The guidance draws on international best practice and the lived experience of maritime SAR professionals. The IMRF’s guidance supports both newcomers and experienced planners: it can be used in full as a foundation document or consulted chapter by chapter to fill specific gaps in existing plans.

Alongside this, the IMRF has also developed a concise Summary Guidance, offering a practical and accessible overview.

This also links closely to the IMRF’s #SARYouOK? initiative, which promotes mental health and  wellbeing across the global SAR community. Sometimes in a rescue scenario, the burden of decisions about where to commit resources can stay with the responders long after an incident ends. By providing a recognised, evidence-based protocol, the Multiple Persons in Water Triage Tool can help reduce moral stress by showing these decisions are made within an established framework designed to save as many lives as possible. In that sense, the tool supports not only operational decision-making, but also the wellbeing of rescuers.

Together, all these resources form part of a wider body of work that supports maritime SAR organisations globally in planning for MROs, strengthening response capability, and supporting responder wellbeing. While MROs may be rare at a national or local level, they are occurring with increasing visibility worldwide, and no jurisdiction is immune.