The correct answers are A. Mechanisms of injury, B. If entrapment occurred, and D. Total number of patients.

During the scene size-up, the EMT performs an initial overview to ensure safety and gather critical information before patient contact. NREMT guidelines emphasize specific elements that must be identified early.

Key components of scene size-up include:

1. Mechanism of Injury (MOI) (A):

Helps predict potential injuries based on how the incident occurred

Essential for determining severity and treatment priorities

2. Entrapment (B):

Determines whether patients are physically trapped

Helps anticipate need for extrication resources and delays in care

3. Number of Patients (D):

Critical for determining if additional resources are needed

Helps identify potential mass-casualty incidents (MCI)

NREMT-aligned references state:

“Scene size-up includes determining the mechanism of injury.”

“Identify the number of patients and need for additional resources.”

“Determine if extrication or special rescue is required.”

Why the other options are incorrect:

C. Severity of the patientsThis is determined during the primary assessment, not initial scene size-up

E. Which patients have diedNot part of initial size-up priorities

F. Site for loading injured patientsThis is part of incident management/transport decisions, not initial size-up

Exact Extracts (NREMT-aligned EMT educational references):

“Determine the mechanism of injury or nature of illness.”

“Determine the number of patients.”

“Assess the need for additional resources and extrication.”

Clinical Priority Summary:

Scene size-up focuses on environmental awareness and resource needs, specifically MOI, patient count, and entrapment, making A, B, and D correct.