Abstract
Mass Casualty Incidents (MCIs) are an understudied field within human factors with much potential for improvement. We conducted a naturalistic study of the emergency medical system in Los Angeles County, producing an operation system diagram of the MCI workflow among all active medical entities, and a list of emergent human factors challenges in MCIs. These issues are as follows: 1) Inconsistent protocols between MCIs and routine events cause critical knowledge lapses; 2) Forced coordination between entities reduces decision-making efficiency; 3) Organizations are slow to change and disseminate new tools; 4) Synchronizing and tracking multiple records creates coordination problems; and 5) Handoffs often result in errors, exacerbated by record coordination issues. We explain each one of these challenges, and provide a series of practical guidelines for future work to resolve the identified problems.