text: Chapter 6
  of strategic or operational significance, employing military capabilities not normally found in conventional
  forces (JP 3-05). Special reconnaissance provides an additional capability for commanders and supplements
  other conventional reconnaissance and surveillance actions.
  6-142. During the conduct of any variation of reconnaissance, the commander may require information
  about a specific aspect of the area of operations (AO). To obtain this information the commander may direct
  a specific focus task which typically requires the use of an organization uniquely trained and equipped for
  the mission. Focus tasks include electromagnetic, engineer, CBRN, and civil reconnaissance.
  6-143. Electromagnetic reconnaissance is the detection, location, identification, and evaluation of foreign
  electromagnetic radiations (energy) (JP 3-85). Electromagnetic reconnaissance supports information
  collection at brigade and higher echelons using assigned electromagnetic warfare personnel and capabilities.
  Information obtained through electromagnetic reconnaissance assists the commander with situational
  understanding and can support signals intelligence activities. Electromagnetic reconnaissance may result in
  electromagnetic protection modifications or lead to an electromagnetic attack against enemy capabilities.
  (For more information on electromagnetic reconnaissance see FM 3-12.)
  6-144. Engineer reconnaissance obtains information about the infrastructure, terrain, or threat. This may
  include data on obstacles, gap crossing sites, airfields, bridges, tunnels, roads, and trails. Engineer units do
  not have designated reconnaissance teams. Engineer reconnaissance is directed and task-organized based on
  mission requirements using assets that would otherwise support other engineer missions. (For more on
  engineer reconnaissance see ATP 3-34.81.)
  6-145. CBRN reconnaissance includes missions to obtain information on suspected or confirmed chemical,
  biological, radiological, or nuclear threats and hazards in an assigned area. CBRN reconnaissance identifies
  indicators of enemy CBRN production or employment and indicators related to civilian or industrial facilities
  that could be weaponized or produce hazards when damaged or destroyed. (For more on CBRN
  reconnaissance see ATP 3-11.37.)
  6-146. Civil reconnaissance is a targeted, planned, and coordinated observation and evaluation of specific
  civil aspects of the environment such as areas, structures, capabilities, organizations, people, or events
  (JP 3 57). Civil reconnaissance verifies or refutes civil information, supports operational environment
  assessments, and detects and monitors changes in the civil component. It is conducted over time through
  routine engagement and patterned civil observance using active and passive sensors, virtual sensors, and
  other means. (For more information on civil reconnaissance see FM 3-57.)
  SECURITY OPERATIONS
  6-147. Units may perform security tasks to the front, flanks, or rear of their main body, and they must be
  aware of enemy threats in all domains relevant to their assigned area. The main difference between the
  performance of security and reconnaissance tasks is that security tasks orient on the force, area, or facility
  being secured, while reconnaissance tasks orient on enemy forces and terrain. Security tasks are supporting
  efforts. The ultimate goal of security operations is to protect main body forces from surprise and deny enemy
  freedom of action to collect on friendly forces. The protected force may not always be a military force; it can
  also be the civilian population, civil institutions, and civilian infrastructure in the unit’s assigned area.
  6-148. There are a number of general considerations when performing security operations. These apply to
  all security tasks, but they are most applicable to the performance of screen, guard, and cover tasks. The
  screen, guard, and cover tasks share many common control measures, starting with boundaries defining the
  security area. The main body unit establishes the security area. For a security force operating to the front of
  the main body, the lateral boundaries of the security area are normally an extension of the lateral boundaries
  of the main body. The security force’s rear boundary is normally the battle handover line. (See ADP 3-90 for
  additional information on common security control measures for security operations.)
  6-149. Security operations are those operations performed by commanders to provide early and accurate
  warning of enemy operations, to provide the forces being protected with time and maneuver space within
  which to react to the enemy, and to develop the situation to allow commanders to effectively use their
  protected forces (ADP 3-90). The four types of security operations are area security, cover, guard, and screen.