The crime-scene specialist (or crime-scene examiner as your book refers to this person) is surveying the scene and taking visual documentation of its state pre-evidence collectors/specialists. What are the major reasons for surveying or SCANNING the Scene?

To determine the safety of the scene and what special skills this examiner will need to use.

To determine how long ago the crime may have happened and how much blood will need to be cleaned up.

To determine if the location is a primary or secondary crime scene and to determine which type of specialist may be needed at the scene.​