performance of security subsystems and create vulnerabilities in system
b) Clear zones to permit unimpeded surveillance and observation by
security forces via electronic direct means. Clear zones are also used to
create a friendly environment for exterior sensor systems.
c) Fences to delineate boundaries of restricted areas and form the
outer perimeter of the security system to delay access to intruders. Fences
also limit the environmentally generated causes of nuisance alarms on
exterior sensor systems caused by animals, blowing debris, etc.
d) Walls and other structural components to prohibit and delay
access and form an inner series of perimeters for specific assets.
e) Portals to control the flow of persons, materials, and vehicles
into and exiting protected areas. Portals become the focal points for
several elements in related security subsystems.
f) Hardened and special purpose structural materials to resist and
delay hostile attack, provide protection to personnel located within, and
protect against covert gathering of classified information.
g) Locking devices to restrict access to protected areas to
specific groups or individuals.
h) Special purpose, limited application response mechanisms which
can be remotely activated to deter and delay intruder penetration of highly
2.4 Detection Subsystem. The detection subsystem provides electronic
sensing and reporting of man, machine, and contraband items moving across,
over, under, or through protected areas and perimeters or through control
points. This subsystem increases control over specific points or spaces
within a protected area by electronically sensing one or more types of
phenomena and reporting outputs to the security response organization. See
the potential inventory of detection subsystem elements in Figure 4.
2.4.1 Detection Subsystem Elements. Specific detection subsystem
requirements will be in accordance with the needs and priorities of local
activity commanders and applicable Navy and DoD directives. The principal
exceptions to this are in sites possessing nuclear assets or conventional
AA&E and those locations having extensive exterior perimeter sensor
requirements. These fall within the purview of Naval Electronic Systems