accident: an unplanned event that interrupts the completion of an activity and that may include injury or property damage
causation: underlying factors in a chain of events that end in an accident or incident; also called root cause
incident: an unexpected event that did not cause injury or damage this time but had the potential to do so
P.A.S.S.: an acronym representing the four steps necessary for the safe use of a fire extinguisher: Pull the pin; Aim the nozzle; Squeeze the lever; Sweep the hose