Carbon Footprinting of North American Emergency Medical Services Systems

Abstract

Objectives. This study was undertaken to characterize the carbon emissions from a broad sample of North American emergency medical services (EMS) agencies, and to begin the process of establishing voluntary EMS-related emission targets. Methods. Fifteen diverse North American EMS systems with more than 550,000 combined annual responses and serving a population of 6.3 million reported their direct and purchased (“Tier 2”) energy consumption for one year. We calculated total carbon dioxide equivalent (CO₂e) emissions using Environmental Protection Agency, Energy Information Administration, and locality-specific emission conversion factors. We also calculated per-response and population-based emissions. We report descriptive summary data. Results. Participants included government “third-service” (n == 4), public utility model (n == 1), private contractor (n == 6), and rural rescue squad (n == 4) systems. Call volumes ranged from 800 to 114,280 (median 20,093; interquartile range [[IQR]] 1,100–55,217). Emissions totaled 46,941,690 pounds of CO₂e (21,289 metric tons); 75%% of emissions were from diesel or gasoline. For systems providing complete Tier 2 data, median emissions per response were 80.7 (IQR 65.1–106.5) pounds of CO₂e and median emissions per service-area resident were 7.8 (IQR 4.7–11.2) pounds of CO₂e. Two systems reported aviation fuel consumption for air medical services, with emissions of 2,395 pounds of CO₂e per flight, or 0.7 pounds of CO₂e per service-area resident. Conclusion. EMS operations produce substantial carbon emissions, primarily from vehicle-related fuel consumption. The 75th percentiles from our data suggest 106.5 pounds of CO₂e per unit response and/or 11.2 pounds of CO₂e per service-area resident as preliminary maximum emission targets. Air medical services can anticipate higher per-flight but lower population-based emissions.

Key words: :

• emergency medical services
• transportation of patients
• ambulances
• greenhouse effect
• air pollution
• climate change
• global warming
• carbon footprinting.