Ok they think to have an emergency back up power supply that is independent of the main systems for a holo deck (a system that was specifically cited in several TNG and Voyager episodes as being very power hungry), but nowhere on the ship, even in the "designated common/refuge" areas such as Sick bay do they have any independent emergency life support systems...or even oxygen masks (something you'd want if just in case of a fire/smoke)
Also and I know this is me being picky and it's done for the drama, but "life support is off, we've only got a few minutes or air" when there are tens of thousands of cubic meters of air in the ship, and even on the bridge there is hundreds of cubic meters, and I won't mention how life support was off but artificial gravity was still functioning (you can survive floating in zero g for a long time, you can't survive not breathing for more than a few minutes).
Sorry just having a little moan, I really enjoyed the episode but that sort of thing does make me roll my eyes given it would indicate the designers of the ships had no idea of the what should be a priority for survival I can imagine Star Fleets ship architects having a conversion:
Captain Berkley: "You know in the event of a seriously dangerous situation we should do something for the crew"
Ship architect: "you mean put in some basic fail safes like independent emergency life support in the shelter areas, engineering and the bridge"
Captain Berkley: "No make sure the holodeck can keep running so Geordie can go on a date"
Ship architect: "..."