Standby personnel must have appropriate equipment to minimize the danger to themselves during rescue efforts. They must be equipped with pressure demand or other positive pressure SCBA, or a pressure demand or other positive pressure supplied-air respirator with auxiliary SCBA. Retrieval equipment must be used unless its use would increase the overall risk associated with entry into or rescue from the IDLH environment. Situations exist in which retrieval lines (e.g., harnesses, wristlets, anklets) may pose an entanglement problem, especially in areas in which air lines or electrical cords are present in the work areas in which the IDLH atmosphere occurs. Most of the time, however, rescue with retrieval equipment is effective, and much safer for the rescuers.