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In the chosen answer for What size hole in the International Space Station would be catastrophic, we find that a 0.6cm hole would depressurize the ISS to life threatening levels in 14 hours. A 20cm hold would do the same in 20 seconds.

The first step to dealing with such an emergency would be to isolate the astronauts in a non-leaky module. How long does it take the astronauts to isolate themselves in a safe module?

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  • $\begingroup$ My guess is that the actuaries requested such numbers before construction began. $\endgroup$
    – Cort Ammon
    Commented Dec 1, 2021 at 17:29
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    $\begingroup$ My notes are too old (pre Crew Dragon) to answer this :( $\endgroup$ Commented Dec 1, 2021 at 20:50
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    $\begingroup$ @uhoh When I wrote the question, I assumed that in such a catastrophic incident, one would act quickly, and isolate any module that happens to be convenient. Organic Marble's comment now makes me wonder if the procedures always isolate the astronauts in an escape vehicle (Dragon/Soyuz). In such a case, the particular vehicle's quirks would be quite important. $\endgroup$
    – Cort Ammon
    Commented Dec 2, 2021 at 19:27
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    $\begingroup$ @OrganicMarble An answer for an older procedure would be applicable. Although I admit that its a fascinating thought that the emergency procedures might have changed enough with Dragon to materially change the rate at which they can be accomplished, like how seatbelts changed cars. $\endgroup$
    – Cort Ammon
    Commented Dec 2, 2021 at 19:29
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    $\begingroup$ In the "old days" - prior to Crew Dragon and MLM - the crew would shelter in the MRMs to which their Soyuzes were docked as well illustrated on page 349 of nasa.gov/sites/default/files/atoms/files/… Isolating a module involves a bit more than closing the hatch - when the crew or the onboard system triggers the alarm, there is a software controlled response that closes intermodule ventilation valves, etc. But the ISS now is sufficiently different from "my day" that I don't know how applicable all this is. $\endgroup$ Commented Dec 2, 2021 at 20:33

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NASA allocates thirty seconds for actual hatch closure. The maximum required module isolation time is 3 minutes, which includes crew response time, removing any stowage blocking the hatch, and/or disconnecting cable drag-throughs, and closing the hatch.

The ISS Safety Requirements Document SSP 51721, Appendix D.4.9.6.3 Rationale – Volume Isolation (pg 289 of the linked PDF) states:

The integrated assessment allocates 1 minute for crew reaction time (including items such as waking up, translating to the hatch, and/or egressing end item apparatus) and 30 seconds for actual hatch closure. In an emergency situation, the intermodule ventilation valve is closed automatically to ensure environmental isolation and although the crew would confirm the valve is closed, it is not considered an impact to the timeline. Time may also be required to clear the hatch of drag throughs, etc.

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