The NHS Prehospital Major Incident Triage Tool (MITT) can be used to triage patient in a mass casualty event.

Patient selection: mass casualty event


Criteria for death - either of the following:

(1) not breathing and open airway

(2) if the patient is < 12 years and submersion, immersion, or smoke inhalation, then not breathing after rescue breaths


Criteria for Level 1 - either of the following:

(1) catastrophic bleeding (attempt control of bleeding)

(2) not walking AND any of the following:

(2a) does not respond to voice

(2b) age <= 2 years

(2c) breathing rate < 12 or > 23 breaths per minute

(2d) heart rate >= 100 beats per minute


Criteria for Level 2 (yellow):

(1) not walking and heart rate < 100 beats per minute


Criteria for Level 3 (green):

(1) walking (and not with catastrophic bleeding)



• Bradycardia is not scored.

• If the patient is not walking and does not meet any of the criteria, then designated level 2.

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