section_path: Safety concerns/Equipment hazards/Extravehicular activity
section_name: Extravehicular activity
paragraph_text: Extravehicular activity
  
  Tasks outside a spacecraft require use of a space suit. Despite the risk of mechanical failures while working in open space, there have been no spacewalk fatalities. Spacewalking astronauts routinely remain attached to the spacecraft with tethers and sometimes supplementary anchors. Un-tethered spacewalks were performed on three missions in 1984 using the Manned Maneuvering Unit, and on a flight test in 1994 of the Simplified Aid For EVA Rescue (SAFER) device.