text: Chapter 7
  which means estimating a higher consumption of classes III and V, or simply increasing the amount of
  emergency classes III and V resupply at the combat trains command post.
  SUSTAINMENT OF SECURITY OPERATIONS
  7-56. Security missions tend to be defensive in nature. Security operations must make the best use of
  available preparation time and sustainment resources. As with reconnaissance, emphasis on any particular
  consideration varies with the mission assigned and shifts during mission execution. Security missions include
  screen, guard, cover, and area security. As they are able, units conducting security operations utilize a
  deception plan for sustainment preparations and operations.
  SCREEN
  7-57. Screen operations can occur at any level. The FSC supports screen operations at the troop level.
  Sustainment planning for units conducting screen operations includes considerations for increased use of
  class III (B) and class V. Considerations for the pre-position of limited amounts of ammunition, petroleum,
  oil, and lubricant, and barrier material in centrally located forward positions should be included. Screening
  units conduct resupply during limited visibility to reduce the chance of enemy interference, and emergency
  resupply well forward during lulls in the battle or as required. Sustainment units supporting screen operations
  should select MSRs that do not interfere with the movement of maneuver units. Units should plan mobility
  operations to maintain MSRs. Plans should limit the forward flow of supplies to supplies essential for the
  operation only and should include the destruction of supplies and equipment (except medical) not evacuated.
  When time or the enemy situation constrains forward repair of equipment, screening units should prioritize
  recovery and evacuation of equipment to preclude loss to the enemy. Units should utilize all available
  noncombat vehicles to tow disabled vehicles.
  GUARD
  7-58. Units conduct guard operations at the battalion level and above. Sustainment planners for units
  conducting guard operations consider echeloning sustainment assets. Units conducting guard operations
  should plan for displacement of sustainment assets so uninterrupted support continues. Units conducting
  guard operations should understand that sustainment units cannot provide support while displacing. Units
  conducting guard operations use push packages of critical supplies on a scheduled basis and continues routine
  resupply until the using unit requests otherwise. Sustainment planners request additional sustainment assets
  from higher headquarters to support attachments or extended operations. Units conducting guard operations
  plan for displacement of support assets and supplies early to keep routes open and preclude unnecessary
  interference with maneuver units.
  7-59. Since the guard force must protect the main body by fighting to gain time, while also forcing the enemy
  main body to deploy early, the guarding unit should prioritize forward repair of equipment as much as
  possible to avoid being decisively engaged. If displacing to avoid decisive engagement, units should prioritize
  recovery over forward repair until they reach a suitable time and location to continue forward repair. If units
  have met triggers for transition, they should prioritize recover and evacuation of equipment. In addition,
  because guarding is defensive in nature, guarding units should also plan for an increased usage of class IV
  material and supplies.
  COVER
  7-60. The BCT executes cover operations. Cover operations require full BSB sustainment support with the
  probability of echeloned support from above brigade, such as the sustainment brigade or medical brigade.
  Sustainment for units conducting covering operations consists of the same factors as the screen and the guard
  at the BCT level. Cover operations consider additional transportation requirements for the movement of all
  essential classes of supply. Cover operations consider a plan to compensate for lost sustainment capability,
  and as missions become more dynamic in execution, determining ways to increase the mobility of forward
  support assets to maintain pace with the unit. Cover operations anticipate greater numbers of civilians
  on the battlefield and detainees than screen or guard operations.