text: Chapter 6
  6-20. Figure 6-1 shows an example safety zone for when power lines fall within 1,000 meters of the
  drop zone.
  Figure 6-1. Recommended safety zones for high-tension lines.
  Other Obstacles
  6-21. This includes anything else, such as barbed wire fences, swamps, rocks, ditches, steep inclines, or
  gullies, that could injure parachutists, damage or prevent the recovery of equipment, or interfere with the
  mission.
  ACCESS
  6-22. Ground unit commanders should avoid any DZ that has a major obstacle between it and the
  objective area. Ground unit commanders should also make sure the area has adequate routes to conduct
  troop movement and to recover equipment.