ABSTRACT
Currently there is much disagreement on the best tools for measuring situation awareness (SA) as well as the nature of the processes that underlie it. The present project sought to assess the appropriateness of two commonly used techniques, SAGAT and SPAM, by examining the intrusiveness of each to operator SA and workload. This was done by manipulating whether or not scenarios were paused and operator displays blanked during probe presentation-two of the key features distinguishing SPAM and SAGAT. The results indicated that both of these factors have an effect on SA and workload. We also found that the intrusiveness associated with blanking and not pausing scenarios depended on the type of information being queried. In particular, making information more difficult to access from external displays had a more negative effect on the ability to answer queries pertaining to information regarding specific aircraft as opposed to general scenario characteristics. These results support the Situated approach to SA, which holds that operators often off-load information to their environment to limit what they have to store internally.
