In an MPS, incidents involve up to how many patients?

• A. Up to 25
• B. 26-99
• C. 100 or more
• D. 1-10

Answer: (A)

Mass Patient Scenarios describe multi-patient incidents that are organized and manageable with standard field resources. The threshold is up to 25 patients, which keeps the scene within a level where responders can coordinate using typical EMS teams and incident command structures without escalating to a full mass casualty operation. Knowing this helps determine how to allocate units, assign roles, and implement triage and treatment plans efficiently. If the patient count exceeds 25, the situation becomes a larger mass casualty incident, requiring broader mutual aid, more extensive triage, and more complex resource management. So, the up to 25 limit defines a mid-size multi-patient event, not a single-patient scenario and not a large-scale MCI.