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In light of this answer, where except for a few cases, space walks from the ISS are usually performed starting about a month after arrival at the ISS, are there any rules, policies, or guidelines that space agencies have in place regarding spacewalks soon after arrival in space and zero-g?

This question is not restricted to the ISS, but the focus is on longer duration, space-station-based walks.

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    $\begingroup$ Eagerly awaiting the n st installment, “what’s the shortest interval between spacewalks of photogenic astronauts greater than 5’8” in height?” $\endgroup$ – Russell Borogove Mar 31 '18 at 4:15
  • $\begingroup$ @RussellBorogove we don't have a photogenic-astronauts tag yet. $\endgroup$ – uhoh Mar 31 '18 at 4:20
  • $\begingroup$ Depending on how you define current the shuttle mission spacewalks where all rather soon after launch considering the total lenght of those missions. $\endgroup$ – lijat Mar 31 '18 at 6:51
  • $\begingroup$ @lijat thanks, that's a good point. I've made an edit accordingly. $\endgroup$ – uhoh Mar 31 '18 at 6:56
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    $\begingroup$ They should be space-adapted (not vomiting).... $\endgroup$ – Organic Marble Mar 31 '18 at 11:18
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ISS flight rules have not been published publicly AFAIK. Here are the Shuttle flight rules concerning EVA scheduling.

Sorry for the "yelling" but that is how the document is written. The rules are in all caps and bold. The rationale is in italics.

  • A "scheduled EVA" is any EVA incorporated into the nominal flight plan. [interpretation - an EVA specifically planned and trained for as part of the mission]
  • An "unscheduled EVA" is used to achieve/enhance the mission objectives of the orbiter or its payloads. It is not part of the flight plan. [interpretation - an EVA being carried out to resolve an issue, not specifically planned and trained for. May be covered by generic training]

(Defined in rules A15-4 and A15-5)

A15-14 SCHEDULED AND UNSCHEDULED EVA CONSTRAINTS

A. NO SCHEDULED EVA WILL BE PERFORMED PRIOR TO MET 72 HOURS.

During adaptation to zero-g conditions, moving about may provoke symptoms of illness. The activity associated with putting on a suit would increase the chance of an EVA crewmember being ill and potentially endanger the crewmember with vomitus in the suit.

B. UNSCHEDULED EVA’S:

  1. NO UNSCHEDULED EVA SHALL OCCUR DURING THE FIRST 24 HOURS OF FLIGHT.
  2. AN UNSCHEDULED EVA MAY BE PERFORMED PRIOR TO MET 72 HOURS ONLY IF AN ASSESSMENT OF CREW HEALTH HAS BEEN ACCOMPLISHED BY THE FCR SURGEON AND APPROVED BY THE FLIGHT DIRECTOR.

Asymptomatic crewmembers may be able to safely perform an unscheduled EVA before MET 72 hours. An accurate assessment of the health status of the EVA crew can be made by the FCR surgeon during a private medical conference.

C. NO SCHEDULED OR UNSCHEDULED EVA SHALL BE PERFORMED ON ENTRY DAY.

  1. FOR A FLIGHT USING A SINGLE CREW SHIFT, A SCHEDULED OR UNSCHEDULED EVA MAY BE PERFORMED ON THE DAY BEFORE ENTRY ONLY IF AIRLOCK INGRESS IS COMPLETED NOT LATER THAN CREW SLEEP MINUS 7 HOURS.

  2. FOR A FLIGHT USING DUAL SHIFT OPERATIONS, A SCHEDULED OR UNSCHEDULED EVA MAY BE PERFORMED ON THE DAY BEFORE ENTRY ONLY IF AIRLOCK INGRESS IS COMPLETED NOT LATER THAN CREW SLEEP (NONENTRY TEAM) MINUS 4.5 HOURS.

An EVA may be done on the day before entry if there is adequate time post-EVA to perform required activities. These activities include airlock repress, post-EVA, EMU maintenance recharge, post-EVA entry prep, cabin stow, and presleep. Seven hours is considered the minimum amount of time to accomplish these activities for a single shift flight. FCS C/O, RCS hot fire, and cabin repress activities must also be performed but can be overlapped with post-EVA and cabin stow activities. For an unscheduled EVA on the day before entry, it will be necessary to perform this EVA as a “quick response” EVA (i.e., the EMU C/O and cabin depress will need to be done on the day prior to the EVA). For a dual shift flight, 4.5 hours is considered the minimum due to cabin stow occurring on entry day for the nonentry team.

Source (huge pdf)

Acronymology:

  • EVA - Extravehicular Activity (spacewalk)

  • MET - Mission Elapsed Time

  • FCR - Flight Control Room (Mission Control Center)

  • EMU - Extravehicular Mobility Unit (spacesuit)

  • FCS C/O - Flight Control System Checkout (activity performed prior to entry to ensure the orbiter is in good shape for atmospheric flight)

  • RCS - Reaction Control System

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