Extra-vehicular activity

Extra-vehicular Activity, often abbreviated simply to EVA, is the term applied to external operations by specialist personnel in a vacuum environment outside of a spaceship.

Civilian welders and technicians perform EVA's in order to repair ships, such as that performed upon the UNSC Gettysburg at the Eridanus System.

Combat EVA's pose a significantly greater risk to those performing it, due to the chance of suit decompression in the vacuum. The Master Chief has performed four known combat EVA's: At Chi Cheti, in 2525, he inserted into a Covenant warship with Kelly and Sam, planted a missile warhead, and extracted him and Kelly; At Reach, in 2552, he performed another EVA in order to neutralize an orbiting station in accordance with the Cole Protocol. He performed another aboard the Ascendant Justice while in an anomalous slipspace dimension, the first known slipspace EVA, and another at Earth, clearing hostiles off the outside of the Cairo Orbital Defense Platform.

The Covenant also perform EVA's. Ranger Elites use specialized vacuum-sealed armor to protect themselves from the effects of vacuum, in order to plant antimatter bombs and support boarding teams.

Both the UNSC and Covenant operate specialized EVA-designed armor variants:
 * Mark VI MJOLNIR Powered Assault Armor/V variant
 * Assault Harness