EMS Triage: Sorting Through the Maze


The injuries caused in events such as the Oklahoma City bombing; the terrorist attacks on 9/11/2001; and, more recently, the Virginia Tech campus shooting have drawn attention to the need for a system to handle large numbers of casualties at a time. Many emergency response organizations have chosen systems to assist in providing adequate emergency medical care in a mass-casualty event. As these organizations consider which system to use, questions arise, such as “How does the system work?” and “What are the advantages and disadvantages of each system?”


In all of the triage systems, the following words are used in the same way:

  • Mass Casualty—any number of casualties produced in a relatively short time that overwhelms the available medical and logistic support capabilities.
  • Triage—the sorting and allocation of treatment to patients, especially battle and disaster victims, according to a system of priorities designed to maximize the number of survivors.
  • Sieve—sift.


The word triage comes from a French term trier, meaning “to sort.”1 Napoleon’s army doctor carried out some of the first documented triage methods. Triage, originally designed for use in the battlefield, is now widely used across the world for management of mass casualties. With the limited resources in the battlefield setting, military medical personnel had to determine the priority in which soldiers would receive medical care. As military field medicine has been adapted, the street triage methods have been modified to meet the needs of today’s fire and EMS providers. In recent years, triage has been used in many highly covered incidents worldwide, including the Oklahoma City bombing; the terrorist attacks on 9/11/2001; the London train bombings; and the Virginia Tech shooting.


1. Simple Triage and Rapid Treatment (START)

General Information: The START system was designed in the 1980s as a result of a partnership between the Hoag Hospital System and the Newport Beach (CA) Fire Department. The purpose of the system was to assist hospital personnel in quickly organizing hospital resources in preparation for receiving victims from a mass-casualty incident. Since its creation, the START system has become a widely recognized and used system.

(1) A typical triage tag. [Courtesy of Disaster Management Systems, Inc. (www.triagetags.com).]

Methodology: The primary goal of the START triage system is to “do the greatest good for the greatest number.” START is designed to allow providers to assess victims in less than one minute to determine the severity of injuries and the need for additional medical care. During the assessment of each victim, a rescuer’s primary focus is on respirations, pulse, mental status, and ability to walk. Based on the findings, a rescuer appropriately categorizes patients.

Categories: Triage of patients using the START system categorizes patients into four groups, designated by colors.

  • Immediate—Patients are tagged “RED.” These patients experience problems with respirations, perfusion, and mental status. They require immediate medical attention and are the first to be transported from the incident.
  • Delayed—Patients are tagged “YELLOW.” These patients often suffer from burns and do not have airway problems, major or multiple bone or joint injuries, and back or spinal injuries. They will survive if definitive medical care is not received immediately.
  • Minor—Patients are tagged “GREEN.” They are often considered the “walking wounded” and may suffer from cuts, scrapes, and sprains and respond to the request to walk from the scene. These patients would often be considered for refusals if they weren’t part of a mass-casualty incident.
  • Deceased/nonsalvageable—Patients are tagged “BLACK.” They are not breathing. Although they would be resuscitated in a “normal” situation, the resources necessary for that effort aren’t available.

Strengths: One of the most significant strengths of the START system is that assessment of patients is designed to be completed in less than a minute. The ability to complete primary triage so quickly allows responders to move from patient to patient quickly, allowing them to “do the greatest good for the greatest number.” Another positive aspect of the START method is that it was designed to integrate into the incident command system (ICS) structure. This ensures that departments that use the START methodology can maintain National Incident Management System (NIMS) compliance while working to manage mass-casualty incidents.

Weaknesses: One recognized weakness of the START system is the secondary triage system. Although secondary triage does occur in the START process, it normally occurs prior to any treatments. Therefore, secondary triage does not take into consideration any improvement in patient conditions because of treatments received.

2. Sacco Triage Method (STM)

General Information: Dr. Bill Sacco created the Sacco Triage Method (STM). He analyzed more than 100,000 patients to design his system. The STM focuses not only on patient condition but also on the number of resources available for management of the mass-casualty event.

Methodology: The primary goal of the STM is to maximize the expected number of survivors by using an evidence-based, outcome-driven method designed to be used on a daily basis, not only during a mass-casualty incident. Categorization focuses on respirations, pulse, and motor response. Each assessment is scored on a scale of one to four; scores are combined to determine the category in which the victim is placed.

Categories: This method does not specifically designate categories with colors or terms. Categories are created based on the assessment scores providers assign to the patients. Patients who receive a score of zero displayed no signs of life; patients who receive a score of 12 are minimally injured or not injured at all. Patients who receive the lowest scores are considered in need of the highest level of care and are transported first.

Strengths: One of the major strengths of the STM is that it takes into consideration all regional resources in making the triage and transportation decision. The computer software used monitors patient categorization as well as the available number of transport vehicles in determining which patients to transport from the scene at any given time. Another aspect of the STM that makes it beneficial for the departments that use it is that they can use the method on everyday responses. The constant use of the triage protocol ensures that responders become familiar with the system so that it is second nature to them when they need to use it in a mass-casualty situation. The STM allows for reassessment of patients to upgrade or downgrade their triage categorization based on their response to treatments and other factors.

Weaknesses: Because the STM relies on a computer system, departments must purchase the software to be able to use the system as it was designed. This may prove cost prohibitive for many departments, since it would involve ensuring the availability of computers for the field and any supporting equipment needed. Another negative aspect of this method is that the forms used in the system are not NIMS-specific. A locality that chooses to use the STM may have problems working in mutual-aid response situations with localities that use the standard NIMS forms.

3. Triage Sieve and Sort

General Information: This method is the triage system used most often in the United Kingdom to assist in mass-casualty management. It is designed to provide primary and secondary triage. The primary triage is the Triage Sieve, during which providers quickly sort casualties into groups based on priority of treatment need. The second step, Triage Sort, is a more in-depth assessment; patients are categorized based not only on injuries but also according to available resources for on-scene treatment and transport.

Methodology: The methodology is simple. With the Triage Sieve, what appears to be the standard triage process is used to assess patients. Assessment of the injured victims is first based on the ability to walk and then assessment of airway and adequate breathing. However, unlike other methods such as START, the triage system does not assess for presence of a radial pulse. Instead, the method relies on the assessment of capillary refill to complete the triage of each patient. Another difference in the methodology of the Triage Sieve and Sort is that after assessment is complete, patients are categorized more on the intensity of the interventions required to assist the patient than on their specific injuries.

Categories: As with other triage systems, the Triage Sieve and Sort method places patients into four categories:

  • P1—the Immediate category, identified by RED. These patients will die without life-saving interventions, which may include airway placement, breathing assistance, and major bleed treatment.
  • P2—the Intermediate category, identified by YELLOW. These patients require a significant number of interventions but can survive a few hours without them.
  • P3—the Delayed category, identified by GREEN. These patients may have walked away from the scene when originally asked to do so or may have minor injuries, such as cuts and scrapes.
  • Dead—identified by BLACK. These patients are unsalvageable.

Strengths:One of the system’s strengths is that once the initial triage phase is passed, additional categories can be used to further prioritize patients for treatment and transport. As with START and MASS, the Triage Sieve and Sort system uses an additional category to designate patients who would be unlikely to survive their injuries without immediate assistance. This ensures that those people with the highest probability of survival get treatment. A second strength of the system is the tagging method that ensures that a patient is tracked from beginning to end—documenting initial triage, secondary triage, treatments conducted, and patient personal information. This documentation ensures that all patients are tracked and that continuity of care is maintained throughout the event.

Weaknesses: The method used to accomplish secondary triage in the Triage Sieve and Sort system is a weakness because it is based on a provider’s knowledge of injuries and their effects on the patient’s anatomical structure. A responder with significant knowledge of the anatomical systems and their responses to various injuries may be able to re-triage based on a more specific and better thought-out assessment of the patient than a provider with only a basic knowledge of emergency medical care. This use of personal knowledge removes the standardization of triage and does not ensure that all patients are being triaged in the same manner.

4. Move, Assess, Sort, Send (MASS)

General Information: This method of triage is loosely based on the triage system designed for use in the military setting. However, modifications were made, since the military triage system was not designed for use in mass-casualty incidents. The MASS triage system is taught as a part of the basic and advanced disaster life support (BDLS and ADLS) courses offered throughout the country.

Methodology: Each letter of the acronym stands for a step in the process:

  • M—Move. As with START, providers instruct victims who can move from the scene to move to a recognized place. However, unlike START, providers also instruct victims to move a limb. Based on the patients who do not move a limb when asked, the provider moves to the second stage.
  • A—Assess. Providers move to the patients who do not move limbs and assess them using the standard assessment of Airway, Breathing, and Circulation. Based on the assessment findings of these patients, the providers move into the next stage.
  • S—Sort. Once assessed, patients are sorted into one of four categories (see below). Once placed in categories, providers move to the next step.
  • S—Send. Patients are sent to the hospitals based on the need for additional treatment.

Categories: As with the START triage system, the MASS system categorizes patients into four categories, based on the need presented (referred to as “ID-me”):

  • I—Immediate. Patients who could not move limbs when requested to and who have open airways.
  • D—Delayed. Patients who were able to move limbs when directed to by the rescuer.
  • m—Minimal. Patients who were able to move from the scene when instructed to do so by the rescuer.
  • e—Expectant. Patients with no airway, respirations, or circulation.

Strengths: As with the previously discussed triage methods, the MASS system allows for additional triage of the “Immediate” patients. After the initial categorization of all “Immediate” patients, responders can do an additional sorting based on which patients are most critical. Patients who are more likely not to survive, even with additional treatment, are placed in another category that places their treatment and transport priority after “Immediate” patients and before “Delayed” patients. A second strength of the MASS triage system is that it allows civilian and military responders to interact at the scene of major emergencies, because the MASS system is based on the military triage system. This allows for a smoother transition from military to civilian responders and from civilians to military responders.

Weaknesses: One of the most significant weaknesses of the MASS triage system is that it relies on the visibility of patients to determine initial triage priority. In scenes where the rescuer cannot see all patients or forgets which patients could follow commands, the first step of the system would have to be repeated with each patient. This repetition lengthens the time it takes to triage patients. A second weakness is that reprioritization of patients is based not on treatment response but on the number of patients to be transported in a higher-priority group. For instance, if there are only two “Immediate” patients to be transported and 12 “Delayed” patients, the “Delayed” patients would receive a high priority during secondary triage, regardless of whether they are in need of it or not. A third weakness is that, unlike other triage methods discussed in this article, the MASS system does not incorporate a tagging system to identify patients, their priority, and any treatments they may have been given. Fire and EMS systems that use the MASS triage method must also select and train on a tagging system that may or may not fully integrate with the system’s methodology.

5. Careflight

The Careflight triage method is one of the few systems recognized by and used in Australian fire and EMS systems. As with the START method, the MASS method, and the Triage Sieve and Sort method, the Careflight triage method assesses a patient’s ability to walk as the first step in triaging patients. From this first step, the Careflight method also mirrors the START method by focusing on a patient’s airway and breathing status, the presence or absence of a radial pulse, and the ability to follow commands.

6. Reverse Triage

Triage systems, since they originated in the military, have been modified to meet the needs on the battlefield. Since the needs on the battlefield are constantly changing, a system of Reverse Triage was created. Reverse Triage focuses on the need to treat those with the most minor injuries first. This allows for the return of personnel into the field. In the military setting, Reverse Triage is used to return soldiers with minor wounds back to the battlefield so they can continue to support the fight. For fire and EMS providers, Reverse Triage may be necessary in a situation where a large number of medical providers are among those injured and treating their minor injuries will allow them to return to the scene to provide medical care. Although not a standard triage method, the Reverse Triage method may be useful to emergency responders. In terrorism preparedness courses, first responders are warned that they are becoming secondary targets in terrorist events. Should a secondary attack occur, Reverse Triage would allow more responders to continue helping civilian victims.


Since the inception of triage, many variations have been created and are in use. A Virginia State Office of EMS survey of state EMS agencies across the United States conducted in 2007 found that of the 28 respondents, 71.4 percent of the states recognize the START system, 10.7 percent recognize a regional system, 3.5 percent recognize the MASS system, and 14.3 percent have no recognized state system.

(2) The Virginia State EMS triage tag used with the START system. (Photo by author.)



Regardless of the system your agency chooses, training in the use of triage and mass-casualty management is a necessity. Training should emphasize the assessment and methodology of the triage system as well as provide practical application of the information. Ensuring that each provider can implement the triage system in a real-life situation is important to establishing a successful mass-casualty management system. Training should also be provided to any individuals who may interact with fire and EMS personnel while managing the mass-casualty incident. Police officers, dispatchers, nurses, doctors, and others who may interact with the scene and the first responders should have a basic understanding of the triage system. This ensures effective communication and interaction among all individuals involved in the mitigation of the incident.


1. www.merriam-webster.com/dictionary/triage. Accessed January 28, 2008.

Additional Resources

KAREN OWENS is the BLS management specialist for Henrico County (VA) Division of Fire, where she oversees BLS training and assists with ALS programs. Previously, she was employed by the Virginia Office of EMS, where she oversaw emergency operations training programs, including MCI management. She has a B.A. degree in psychology and an M.A. degree in public safety leadership. She is a Virginia-certified firefighter and EMT-B instructor.

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