Directory of EMS organizations.
D000552:Ambulances; D000575:American Nurses' Association; D001244:Association; D002170:Canada; D003422:Critical Care; D004181:Directories as Topic; D004632:Emergency Medical Services; D004634:Emergency Medical Technicians; D004635:Emergency Medicine; D005390:Fires; D018635:Rescue Work; D012955:Societies, Medical; D014481:United States