text: Chapter 9
  BOUNDARIES
  9-57. A boundary is a line that delineates surface areas for the purpose of facilitating coordination and
  deconfliction of operations between adjacent units, formations, or areas (JP 3-0). (Refer to JP 3-09,
  FM 3-09,andFM 3-90-1 formoreinformation.)Boundariesaffectfiresupportintwoways.Theyare(cid:650)
  (cid:122) Restrictive.Boundariesare restrictive inthat normallyunits donotfireacrossboundariesunless
  the fires are coordinated with the adjacent unit or the fires are allowed by a permissive fire
  support coordination measure, such as a coordinated fire line. These restrictions apply to
  conventional and special munitions and their effects. When fires such as obscuration and
  illumination affect an adjacent unit, coordination with that unit normally is required. A
  commander may employ direct fires without clearance at specific point targets that are clearly
  and positively identified as enemy. Targets and their triggers should be kept within the same
  unit’sboundarywithoutoverriding othertacticalordoctrinalconsiderations.
  (cid:122) Permissive. Boundaries are permissive in that a maneuver commander, unless otherwise
  restricted,enjoyscompletefreedomoffireand maneuverwithinhisownboundaries.Thus,units
  may execute joint fires without close coordination with neighboring units unless otherwise
  restricted.
  FIRE SUPPORT COORDINATION MEASURES
  9-58. A firesupportcoordinationmeasure(FSCM)is a measure employed bycommanderstofacilitatethe
  rapid engagement of targets and simultaneously provide safeguards for friendly forces (JP 3-0). The
  followingrestrictiveandpermissiveFSCMs—areusedfrequentlyinairborneorairassaulttasks.SeeJP 3-
  09,FM 3-09,andFM 3-90-1 for a discussionofFSCMs.
  (cid:122) Restrictive Fire Support Coordination Measures. Restrictive measures impose requirements for
  specific coordination before engagement of targets. Restrictive FSCMs are those that provide
  safeguards for friendly forces and noncombatants, facilities, or terrain. Restrictive FSCMs
  include the no-fire area, restrictive fire area, restrictive fire line, fire support area, fire support
  station,andthezoneoffire.
  (cid:122) Permissive Fire Support Coordination Measures. Permissive FSCMs facilitate the attack of
  targets by reducing or eliminating the coordination necessary for the clearance of fires.
  PermissiveFSCMsincludethecoordinated fire line,firesupportcoordinationline,freefirearea,
  andthekillbox.
  AIRSPACE COORDINATING MEASURES
  9-59. Airspace coordinating measures (ACM) are measures employed to facilitate the efficient use of
  airspace to accomplish missions and simultaneouslyprovide safeguards for friendlyforces (JP 3-52). Two
  ACMs–the airspacecoordinationareaand therestricted operationsarea– arefrequentlyused in airborne or
  airassaulttasks.RefertoJP 3-52,FM 3-52,FM 3-90-1 for a discussionofACMs.
  (cid:122) An airspace coordination area is a three-dimensional block of airspace in a target area,
  establishedbythe appropriate ground commander, in whichfriendlyaircraftare reasonablysafe
  from friendly surface fires. The airspace coordination area may be formal or informal
  (JP 3-09.3). The airspace coordination area isthe primary ACM whichreflects the coordination
  ofairspaceforusebyairsupportandindirectfires.(RefertoJP 3-09.3formoreinformation.)
  (cid:122) A restricted operations area (ROA) is airspace of defined dimensions, designated by the
  airspace control authority, in response to specific operational situations/requirements within
  which the operation of one or more airspace users is restricted (JP 3-52). An ROA is used to
  separate and identify areas, examples include but are not limited to artillery, naval surface fire
  support, unmanned aircraft system operating areas, areas of combat search and rescue, special
  operationsforces operatingareas, and areas whichthe area air defense commander hasdeclared
  weapons free. Air defense missions generally have priority over ROAs. (Refer to JP 3-52 for
  moreinformation.)