For example, almost all types of damaged buildings will contain voids or spaces in which trapped people may remain alive for comparatively long periods of time.  To know where these safe places may be, one needs to know the characteristics of various types of construction.  Buildings of the same class and type of construction collapse in much the same way, and common factors are present.  It is important that rescuers study these factors, since this knowledge will prove helpful when extricating casualties.

Ideally, search and rescue teams should have surveillance forms to record important information, including the building type, the collapse site address, the nature of the collapse, the amount of dust present, the presence of fire or toxic hazards, the location of victims, and the nature and severity of injuries.  Victims pronounced dead at the scene should be tagged with an identification number so that the medical examiner's data can later be linked to the search and rescue surveillance form.  Surveillance of search and rescue activities should be used to direct resources to sites where the most good can be done in the first 24-48 hours--the most critical time.