Originally Posted by
weero
I can already see some overzealous agent trying to assess that criterion with no real tools available.
It wouldn't be the gate agent since the battery criteria is for use and the gate agent doesn't know if you are just stowing it for the flight.
Meanwhile, other airlines have the same requirement, because they don't guarantee non-interrupted power is available at every seat. But I don't ask permission, I just plug it in (sans water humidifer so it is low power) at bedtime. For some devices, the batteries are probably important. But a CPAP without power isn't different from not using it at all. If a FA actually stopped me, then the rest of the cabin will likely riot against them because it turns my chainsaw snoring into peaceful breathing.