A Mass Rescue Operation (MRO) is formally defined as a SAR response involving so many persons in distress that available resources cannot handle them using normal procedures. In the Central Mediterranean, operations involving hundreds of people are not exceptional — they are routine.
MROs require adapted procedures: modified triage priorities, different communication protocols, resource coordination across multiple assets, and a sustained physical and emotional demand on everyone aboard. Understanding how MROs work helps you prepare for what is, statistically, the most likely type of operation you will experience on deployment.
A standard rescue involves a manageable number of persons — a small vessel in difficulty, an MOB from a yacht, a stricken fishing boat. The process is sequential and resources are adequate.
An MRO collapses this — the numbers arriving simultaneously exceed what can be handled individually. Every procedure adapts: triage becomes categorical rather than individual, communications increase dramatically, capacity limits become operational constraints, and the sustained duration of the operation creates fatigue challenges for crew.
Operations involving 100–500+ persons are common. The largest operations have involved over 1,000 persons across multiple vessels simultaneously. A humanitarian SAR vessel may rescue several hundred people in a single operation — and then be tasked again before reaching port.
An MRO may last many hours — particularly when RHIB trips are required to recover people from multiple vessels or when hundreds need to be brought aboard in sequence. Crew fatigue management during an MRO is an operational priority alongside the rescue itself.
Triage is the process of prioritising medical care when demand exceeds capacity. In an MRO, the medical team cannot give equal attention to every person simultaneously — they must assess rapidly and direct limited resources to where they save the most lives.
Triage categories are adapted from standard mass casualty systems. In maritime SAR, persons in the water are assessed before those still on the distress vessel — time in the water creates additional medical urgency.
An MRO is a sustained operation. Managing the vessel's physical capacity — space, food, water, medicine — and the crew's human capacity — energy, focus, emotional reserves — are both operational responsibilities.
Every vessel has a capacity limit — not just in physical space, but in water, food, medicine, and sanitation. The HoM and SARCO track numbers throughout an MRO and communicate with the MRCC about capacity. When limits approach, the operational picture changes — other assets may be required, or the vessel may need to proceed to port while the operation continues with other vessels.
Water, blankets, and basic food are distributed as survivors come aboard. The logistics team manages supply rates during an MRO — distributing enough to address immediate need without depleting reserves before all survivors are aboard.
RHIB crew rotation is critical — physical and mental fatigue accumulates rapidly during repeated recovery trips. The STL manages crew rotation. If you are asked to step back from a role during a long operation, this is a fatigue management decision. Rest when directed so you are ready when needed again.
An MRO is emotionally demanding — the scale, the individual stories, the medical cases, the children, the duration. This is the reality of the work. Your organisation will provide a debrief after major operations. Talking to your team, eating, and resting after the operation are not optional recovery steps — they are part of maintaining your ability to function on the next one.
Five questions on MRO procedures and triage.