conscious knowledge of the immediate environment and the events that are occurring in it. Situation awareness involves perception of the elements in the environment, comprehension of what they mean and how they relate to one another, and projection of their future states. In ergonomics, for example, it refers to the operator’s awareness of the current status and the anticipated future status of a system. Situation awareness is influenced by a number of factors, including stress; it may be impaired by cognitive tunneling or social tunneling. Compare ambient awareness; vigilance.