Even if your phone isn’t registered on a network, you don’t have a problem as long as you have a charge in the battery. You phone lets you know that the only number you can dial is a 911 call center, even if the Home screen is locked.
When you call 911 from a landline, the address you’re calling from is usually displayed for the operator. When you’re calling from a cellphone, though, the operator doesn’t have that specific information. So, when you call 911, the operator might say, “911. Where is your emergency?” Don’t let this question throw you; after all, you’re probably focused on what is happening and not on where. Take a moment and come up with a good description of where you are — the street you’re on, the nearest cross street (if you know it), any businesses or other landmarks nearby. An operator who knows where you are is in a better position to help you with your emergency. Your phone does have a GPS receiver in it that 911 centers can access. However, it’s not always accurate; it may not be receiving location information at that moment, as is the case when you’re indoors.
When traveling outside the United States or Canada, 911 might not be the number you call in an emergency. Mexico uses 066, 060, or 080, but most tourist areas also accept 911. And most — but not all — of Europe uses 112. Knowing the local emergency number is as important as knowing enough of the language to say you need help.
If you accidentally dial 911 from your phone, don’t hang up. Just tell the operator that it was an accidental call. She might ask some questions to verify that you are indeed safe and not being forced to say that your call was an accident.
If you panic and hang up after accidentally dialing 911, you’ll get a call from the nearest 911 call center. Always answer the call, even if you feel foolish. If you don’t answer the call, the 911 call centers will assume that you’re in trouble and can’t respond. They’ll track you down from the GPS in your phone to verify that you’re safe. If you thought you’d feel foolish explaining your mistake to a 911 operator, imagine how foolish you’d feel explaining it to the police officer who tracks you down and is upset with you for wasting the department’s time.