In the United States, injuries (all types) may represent the single most important public health problem. The outcome of occupational injuries depends not only on the severity of the injury, but also the rendering of first aid care. This two part lesson discusses the steps in responding to a health or medical emergency, and how to provide first aid to victims. In part 1, we discuss the OSHA regulation; what first aid is; how to recognize and respond to a health/medical emergencies; how to activate the Emergency Medical Service; and how to transfer care to EMS providers.