Which 911 will I reach?

October 6, 2006 9:29 PM

If I dial 911 from my cell phone, does it connect me with emergency services in the area I'm physically calling from, or in the area code of my phone number?

I live in DC, but my cell phone number has a NY area code (my bill is sent to my DC address, so my service provider does know that I don't live in NY anymore). If I call 911 from my phone in DC, will I be connected with the DC emergency services line, or the NY line? What if I'm in a different city altogether (neither the city of my area code nor the city of my cell phone's billing address)? Does the 911 call get routed based on which cell tower my call is routed through, or based on some other factor that may result in me being connected to the wrong city's 911 line in an emergency?

I tried Google and a few other sources, but all I got was a lot of info about how e-911 and GPS tracking in emergencies aren't working right yet. Nothing about how the system decides which operator to connect me to.

posted by Amy Phillips to technology (15 comments total)

DC. If you are on a cell phone and dial 911, you'll be connected to the 911 service associated with the cell-service provider you are roaming on, not on whatever your "home" area code is.
posted by absalom at 9:35 PM on October 6, 2006

(Hopefully just the answer was good enough. You didn't specify that you cared *why* it was so.)
posted by absalom at 9:37 PM on October 6, 2006

Unfortunately, although the FCC has mandated a standardized set of functions for E911, it's still a crazy quilt of implementation, whose details depend on what carrier you have, what your actual location is when making the call, the capabilities of your phone, the capabilities of the cell towers handling your call, and the emergency call center taking your call. Drive 15 miles from home, and you might get a completely different level of response, for better or worse, than you do at home.

You can ask your carrier's customer service folks to clarify the situation for you, but sometimes you have to pound away at it, because even they may not know, at a first level. You can "make a dialing mistake" from your home and work locations to see how the call is actually handled, but again, the procedures may well change without notice to you, as new cell towers are installed, and backend facilities are upgraded.
posted by paulsc at 9:39 PM on October 6, 2006

When I had to dial 911 on my cell (car accident 500 miles from home) it connected me to the local, middle-of-nowhere emergency number, not my hometown.
posted by gatorae at 9:53 PM on October 6, 2006

I called 911 in Moline, Illinois on an Indiana cellphone and got dispatchers in Davenport, Iowa. It wasn't too far off, but they had to transfer me.
posted by thirteenkiller at 9:55 PM on October 6, 2006

Where you are. Not that there's much point in DC!
posted by crabintheocean at 10:07 PM on October 6, 2006

paulsc's got it; here's a quote from the enhanced 911 page:

Phase I requires carriers, upon valid request by a local Public Safety Answering Point (PSAP), to report the telephone number of a wireless 911 caller and the location of the antenna that received the call.

Whatever the current practical limitations, cell phone companies are supposed to be sending public safety folks info about the location of the antenna nearest to where you currently are (which is presumably the one that received the call).
posted by mediareport at 11:03 PM on October 6, 2006

I've dialed 911 three times with two different non-local cell phones over the course of about four years, and every time I've been connected to local dispatchers, not the ones near my area code.
posted by croutonsupafreak at 11:14 PM on October 6, 2006

I used to be a 9-1-1 dispatcher in Indiana...how its SUPPOSED to work, is each cell tower has antennae that are pointing in a certain direction. They are SUPPOSED to look at a map and say "well, calls coming from this sector are generally going to be in X jurisdiction" and then assign the calls that hit that sector to the 9-1-1 center they decide upon.

That doesn't mean you are going to get the correct department as there may be several departments that cover the area and cell phones have little tiny minds of their own and we'd get 9-1-1 calls from Ohio.

reg
posted by legotech at 12:55 AM on October 7, 2006 [1 favorite]

Anecdotally, once I had to tell the dispatcher where I was, since it seemed to be a regional dispatch center, while the other went straight to the local police station.
posted by gilsonal at 5:44 AM on October 7, 2006

You might be interested to know that a cell phone which doesn't currently have service can still call 911. That's required by law.
posted by Steven C. Den Beste at 7:35 AM on October 7, 2006

An ancedotally here in Cincinnati along the Ohio/Kentucky/Indiana border, its not uncommon for calls to get routed to the wrong jurisdiction. Hell, it can happen when the callers give information. After all, there is a "River Road" on both sides of the Ohio River here.
posted by mmascolino at 7:41 AM on October 7, 2006

Living in three different places over the past few months (Michigan, DC, and Rhode Island) with Cingular service, I can tell you that I've been routed to three very different 411 information services depending on where I am.
posted by awesomebrad at 11:51 AM on October 7, 2006

Not to derail but jurisdiction can be really important in the DC area, really important.
posted by Pollomacho at 2:43 AM on October 9, 2006

It depends on where you are. In most of California, you will be routed to CHP dispatch in Vallejo, CA. If you're on a highway in San Jose, and you're using Cingular, you'll be routed to San Jose City dispatch. If you're in the same area and on Verizon, you'll go to CHP. City fire & police are dispatched by the city offices, stuff on a broader scale is handled by county communications. When I'm working an EMT shift, we call directly into the appropriate county communications center with a direct dial number because we're not on the county radios.

The cell companies have really fucked us with e-911.

and awsomebrad - Cingular used to have *all* of the 411 services handled by a company called Metro One. Didn't matter where you were, your call went to them. One of their centers was in Sacramento, CA.
posted by drstein at 2:00 PM on October 9, 2006