5.1 Scene Safety & Hazmat Awareness

Scene Size-Up

The scene size-up is performed before making patient contact and follows a systematic approach every time:

Scene Size-Up Sequence

1. BSI/PPE -- Body Substance Isolation is your FIRST priority. Put on appropriate PPE before approaching the scene.
2. Scene Safety -- Is the scene safe for you, your partner, bystanders, and the patient? Look for hazards: traffic, fire, downed power lines, violence, hazmat.
3. Mechanism of Injury (MOI) / Nature of Illness (NOI) -- Trauma: determine the MOI. Medical: determine the NOI based on the chief complaint.
4. Number of Patients -- Are there more patients than your crew can handle?
5. Additional Resources -- Do you need ALS, fire, law enforcement, utility companies, or hazmat teams?

NREMT Key Point: If the scene is NOT safe, do NOT enter. Stage at a safe distance and call for appropriate resources.

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Hazardous Materials Awareness

EMTs are trained to the awareness level for hazmat incidents. This means you can:

• Recognize a potential hazmat situation
• Isolate the area and deny entry
• Call for trained hazmat responders

You should NOT attempt rescue, decontamination, or containment at the awareness level.

NFPA 704 Diamond

The NFPA 704 placard (the "fire diamond") is found on fixed facilities and some vehicles:

Emergency Response Guidebook (ERG)

The ERG is published by the US DOT and is used during the first 15-30 minutes of a hazmat incident:

• Yellow section -- Look up the 4-digit UN number from the placard
• Blue section -- Look up the material by name alphabetically
• Orange section -- Provides safety and response information for each guide number
• Green section -- Lists initial isolation and protective action distances for highlighted materials

Hazmat Zones

PPE Levels

EMTs typically wear Level D (standard PPE: gloves, eye protection, mask) and operate in the cold zone only.

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Mass Casualty Incident (MCI) Triage

START Triage (Simple Triage and Rapid Treatment)

START triage is used for adult patients during an MCI. Each patient assessment should take 30 seconds or less. The algorithm follows the RPM method:

1. R -- Respirations: Can the patient breathe?
2. P -- Perfusion: Is there a radial pulse or capillary refill <2 seconds?
3. M -- Mental status: Can the patient follow simple commands?

Triage Categories

JumpSTART Triage (Pediatric)

JumpSTART is the pediatric modification for children under 8 years old:

• If a child is not breathing, check for a pulse first
• If pulse is present, give 5 rescue breaths and reassess
• If the child starts breathing, tag immediate (red)
• If no pulse, tag deceased/expectant (black)
• Uses the AVPU scale instead of "follows commands" for mental status
• "Inappropriate" posturing or unresponsive = immediate (red)

Scene Safety in Detail

Scene safety is not a single glance; it is a continuous process from dispatch through transport. Begin gathering information from the dispatch data (the type of call, location, and reported hazards), then evaluate the scene from a distance before committing. Common hazards the NREMT expects you to recognize and manage include:

• Traffic - park defensively, wear high-visibility gear, and use the apparatus to block the lane.
• Violence - for assaults, domestic disputes, or active scenes, stage away until law enforcement secures the scene; never enter a violent scene to reach a patient.
• Electrical hazards - assume downed power lines are live; stay one full span away and wait for the utility company.
• Fire and unstable structures - leave fire suppression and structural rescue to the fire service.
• Hazardous materials - approach from uphill and upwind, keep the scene at a distance, and use binoculars to read placards.

If at any point the scene becomes unsafe, retreat and re-stage - your safety comes before the patient's, because an injured rescuer becomes a second patient and removes a rescuer from the response.

Number of Patients and the MCI Threshold

Counting patients early determines whether your crew can manage the call or whether it becomes a mass casualty incident (MCI) that overwhelms available resources. The moment the number of patients exceeds what on-scene crews can treat with the standard approach, shift from individual care to a triage mindset under the Incident Command System (ICS), request mutual aid, and establish command. Calling for additional resources early is always better than realizing too late that you are overwhelmed - resources can be cancelled if not needed.

The Goal of Triage

The philosophy of MCI triage reverses everyday EMS thinking: instead of devoting maximum effort to the sickest patient, you do the greatest good for the greatest number. That is why a non-breathing adult who does not start breathing after a single airway repositioning is tagged black in START - spending a rescuer on prolonged resuscitation of one unsalvageable patient denies care to several who could survive. Reassess and re-triage patients as conditions change and resources arrive, because a yellow patient can deteriorate to red while waiting.