ICE is a suffix you add to contacts in your phone that you want notified if you end up in, say, hospital having been found unconscious - i.e. you're already in the hands of the emergency services, not summoning them. How some A&E nurse is supposed to nosey through your contacts when she doesn't know the pattern for your unlock screen is a mystery, however.Plus a thing called ICE. Also a 999 call uses every available network not the one you're on. Thankfully!