100 Ways to Mis-Dial 911
There may not be 100 ways to mis-dial the three-digit emergency number 911, but it's close. Thanks to George Fosque for suggesting a place where visitors can submit how 911 is being misdialed, and perhaps lead to some solutions.
While much of the current attention is focused on accidental/unintentional 911 from wireless phones, there still is a considerable problem with accidental calls from wired telephones.
Many of these mis-dials depend upon the caller actually mis-dialing the call. That is, their finger presses an adjacent Touch Tone key--the-called "fat finger." [download this study on human factors research into the Touch Tone keypad layout. Acrobat, pdf format]. Therefore, there is little that PSAPs can do to reduce or limit the errors, and the resulting accidental 911 calls.
This list started out more as a technical compendium, but has been expanded to include more "human" types of 911 misdials. If you have additions to this list, just e-mail us!
Area Codes That Include "9-1"
This is a very common dialing mistake by persons trying to dial a telephone in any of the area codes that contain the digits 9-1. The person either adds another "1" to the end of the two digits, or somehow fumbles and presses an additional "1" key.
There are currently nine such area codes assigned, from 910 to 919 (excluding 911, of course). There are also five other area codes containing the digits "9" and "1" that can be mis-dialed: 901, 931, 941, 951, 971. Thankfully there are no area codes formatted at "X11."
For example, the person intends to dial the number 235-0812 in area code 912. They mis-dial 911-235-0812, and reach the local PSAP instead. In this case, the person forgets to press the Direct Distance Dialing (DDD) prefix digit "1", and their finger hits the "1" button directly to the left of the "2" button on the telephone keypad. As soon as the number "911" is dialed, the remaining digits are ignored, and their call is routed to the appropriate PSAP.
Central Office Codes That Begin "9-1"
The first three number of a local telephone number are known as the "central office code." If this code begins with the digits "91," the chances of an accidental 911 call are increased.
For example, a person intends to dial the number 912-3305, but accidentally dials 911-3305. As soon as the number "911" is dialed, the remaining digits are ignored, and their call is routed to the appropriate PSAP
Certain international dialing codes include the digits "9" and "1," and present problems if callers mis-dial.
Specifically, the country code for calling India is 91, and the city code for calling New Delhi is 11. If the caller forgets to dial the international dialing code prefix "011," the digits "9-1-1-1" would be transmitted. As soon as the telephone system receives "9-1-1" the remaining digits are ignored and the call is routed to the appropriate PSAP.
Dialing Nuremburg, Germany
This one is simple: the city code for dialing Nuremburg is "911."
If the caller forgets to dial the international dialing prefix "011," and then forgets to dial Germany's country code "49," they dial "911," and their call is routed to the appropriate PSAP. This mistake would require the caller to forget many of the dialing steps, but it happens.
Dialing From a PBX
The (almost) universal digit to obtain an outside line from a PBX extension is "9," creating many different methods for mis-dialing 911. Here are some:
Problem: Callers wants to dial 9-011-54-12345678 Internationally. The callers omits the '0' and the PBX sees "911"
Problem: Caller wants to dial 9-1-212-555-1234 Dials 9-1, pauses to look at the number again, then and dials 1-212-555-1234 – PBX sees "911"
Problem: Caller wants to call any area code via 9-1-212-XXX-XXXX Fat fingers the "1" and double dials it as 9-11-212-555-1234 PBX sees "911"
Fortunately, PBX software has become very sophisticated, allowing administrators to filter the dialing sequences to detect these errors, basically functioning like this: 9-1-1 is an emergency call. put it through immediately. 9-1-1 plus any additional digits is a potential misdial, route the call locally and alert local responders.
Cellular: One-Touch Button Accidentally Pressed
Cellular phones have two methods for programming 911 into the phone, and which can lead to accidental calls:
Most handset manufacturers now do not pre-program these features into the phones, after complaints from PSAPs about accidental calls. However, most handset software still allows the user to program the handset in this fashion.
This problem does not occur with handsets that feature a flip-up or flip-down cover over the dialing pushbuttons.
411 and 611
These numbers for "Information" and "Repair Service" are universally by telephone companies, and are prone to mis-dialing. It's easy to see how a caller might press the "1" key instead of the "4" key (1 is directly above the 4 key), and how they might press the "9" key instead of the "6" key (it's just below, and perhaps people flip the "6" in their minds to a "9").
Most modern residential telephones can be programmed to dial any number with the press of one key, or a two-key sequence. Some phones even have specially identified and colored buttons for "Police" and "Fire" numbers. We haven't heard of any telephone manufacturer programming buttons to dial 911 by default. However, it's still possible for the buyer to program a button or sequence of buttons to dial 911, and generate a call accidentally through many different scenarios.
Miscellaneous Devices Dialing 911
There is an entire range of other, non-telephone devices that can be programmed to dial telephone numbers, including fax machines, modems, soft drink vending machines (!), and others. Misdials can occur with these devices if they are improperly programmed, revert to their default settings (Australia had a rash of Coke vending machines dialing "000"), or otherwise go on the "fritz."
In particularly, the telephone numbers assigned to AOL modems for dialing in sometimes start with the digits "91," increasing the risk that it will somehow accidentally dial 911. Apparently Richmond (Virg.) had this problem, but AOL changed their modem numbers to reduce the problem.
Line / Equipment Problems
Every time it rains, the telephone lines go noisy, usually because of water getting inside the lines because of bad insulation (squirrels love to gnaw on the stuff). The water creates an electrical pathway between the wires in the phone line--not quite a short circuit, but enough to create noise and the generation of signals that fool the central office computer into thinking a telephone has dialed 9-1-1.
Consumer telephones aren't know for their durability, and it's possible that the pushbuttons or their switches will become sticky, clogged or otherwise flaky. If the switch for the "1" key is not working correctly, it could generate two transmissions of the digit instead of one, thereby generating a 911 call under certain circumstances.
Cordless Phone — Low Battery
This problem appeared about 5-7 years ago when cordless telephones became popular for homes. The phones would randomly and seemingly without reason dial 911. The calls were somehow traced to the condition of the handset battery: if the handset was left off the base station charger for an extended period, the handset would dial 911. Cordless phones made within the past 2-3 years seem to have solved this problem.
This is a huge category, and one that could be expanded to many pages. However, we've summarized some of the more common sources of 911 calls:
In July 2002 a limited number of WebTV users reported that their device dialed 911. The behavior was traced to a virus that arrived via WebTV's e-mail service, and which the receiver then opened. The virus would cause the WebTV device to shut down, reboot, and then dial 911--naturally a law enforcement response usually resulted from this behavior. TechTV has an article about the virus, which notes that fewer than 20 WebTV users reported the problem.
"The Twilight Zone"
Some misdeals just cannot be explained. Take the case of the dog that dialed 911 (no, the phone wasn't programmed to dial 911--he dialed 911!), and the rotting tomato that dripped down from a basket suspended over the phone, and ended up dialing 911 (perhaps from some type of electrical short circuit within the phone's electronics).
No Initial Dialtone
Thanks to John for pointing out the mis-dials he receives, intended for a hospital with the number 291-1100. He surmises that a quick-dialing person presses the digit "2" before the phone has actually secured a line, and the dial tone is present. Therefore, the only digits recognized by the central office switch are "911." The remaining digits are ignored and the caller ends up talking to a PSAP.
Thanks to Josh for his twice-in-a-million experience: This happened to me twice with my BlackBerry Pearl. It was setup to keylock after inactivity and I just had it in my pocket, with no case. Well, this model has a trackball. When it is in keylock, rolling vertically on the trackball toggles through Unlock, Emergency Call and Cancel. Well, if you choose Emergency call, you have to choose Yes/No, again with vertical scrolling. Apparently walking into my house and fumbling for my keys created just the right sequence to let my pocket exclaim "What is the nature of your emergency?" I quickly figured out what happened and called to explain the situation. My solution was to get a case for the BlackBerry, which serves dual purpose. One is to provide protection from accidental key presses, the second is it puts the phone in a standby state where it won't respond to key presses anyway.
Out of Range
Although cellular telephones are supposed to use any available carrier when making a 911 call, there are limitations in both frequencies and technlogy (CDNA vs. TDMA). It's possible that you dialed 911 and were unable to connect because you were in a bad reception area for your assigned carrier, and technical differences prevent your handset from connecting to another carrier. If you are moving in a car, you may then enter an area of improved reception for your carrier, and the phone will re-attempt to make the 911 call. You may or may not have already contacted a public safety agency, or decided not to contact them, even as your phone is connecting to a 911 dispatcher.
Since we posted this original information, we've received lots of feedback from readers, and have tried to incorporate it into the above information. Here's what some of them had to say:
First, in your example, on some PBXs you would have to dial 9911 because the first 9 would access the trunk, but not be repeated on the trunk. So just dialing 9,11 wouldn't do it. But some PBXs, like ours, have been programmed to translate 911 into 9,911 figuring it's a good thing to do and not make somebody with an emergency call redial.
Second, there's the problem of a tied-up, open line which shows up as no conversation or re-order (fast busy) tones if you ask the telco to go in on the line. It happens like this:
The internal caller wants to dial an outside number ... say, one starting with 919 or perhaps 011, and they fat-finger the dialing sequence, and end up dialing (9) to get an outside line, and then 9119... or whatever. Whoops. So they press the hook, wait a moment, then dial again, this time correctly. If the moment they wait is interpreted by the PBX as a short "hook flash" rather than longer hangup, then the PBX puts the first call (the one that is by now ringing at 9-1-1) on hold, gives them new dial tone and they make the call they originally tried to make. The PBX thinks they're making a consultation call to a third party, or that they are starting to establish a three-way conference call. If they succeed with the second connection and happen to hook flash at this point, the 9-1-1 call will be conferenced with their new call. But they don't usually do that ... they just talk on the new call and meanwhile the 9-1-1 trunk is on hold. At some later point, they hangup. Some PBX's will drop the original call at this point, while others will ring the station that had the trunk on hold. But by this time, 9-1-1 has given up, dispatched officers, and hung up.
I've seen cases where the second call got voice mail, so the caller hung up--but since the far side had not hung up yet, the effect was to conference the 9-1-1 call with the voice mail call. No telling how long it will take the voice mail system to decide to hang up, or how effective the disconnect sequence is. Trying to determine how many milliseconds of on-hook should be ignored, constitute a "flash", or be considered a hangup is not an easy task. So, yes, strange things happen. --- Dan
Keypads wear out. Sometimes the buttons become intermittent, and even develop the ability to send the number twice with a single press (once on the way down, again on the way up). If the number 1 goes bad this way, any number beginning with 91 will reach a PSAP. Kansas City has ten-digit dialing across the state line, and the Kansas side area code is 913. --Dwight
In my ("our"?) PSAP, the number one reason, without exception, is 891. We have the "891" phone code. 891-1338 is the local Chinese joint -- miss the 8, and you get us. Deputies have 891-1xxx telephone numbers, drug dealers call it, all sorts of interesting things happen when people just want to dial an 891 number (the more amusing of which was a young boy, who, upon hearing one of our female dispatchers answer "Anytown 911, where is your emergency?" answered only "... Grandma?"). I guess this holds true for any area that has a x91-xxxx telephone number...
How about misdialing the 011 as 911. This happened to us a few years back. My wife was trying to call her mother and misdialed 011 as 911 and since the call did not go through put the phone down and dialed again. 5 minutes into the conversation a couple of policemen knock at the door wanting to know what the problem was. After a few minutes of discussion one of them realized what could have happened.
Back around 1999 we had a server that would crash on us. Before it did though, we had figured out how to get it to send an email to our pagers and cell phones. To make sure it got our attention, the message originally said "911! Server Crashing" (or something close to that.) Imagine my surprise when one day after apparently bumping my desk enough times, my cell phone started talking to me: "hello, 911, state your emergency." I pull it out of my pocket and explained that I had not called 911. However, as we soon figured out, the cell phone was capable of picking out apparent "phone numbers" from email messages and that's what it had done. Even though I had had the keypad "locked". So, we changed it to "9*1*1" Same thing, the phone figured it was a phone number and offered to dial it for us. (This time since we were testing we could stop it from actually dialing.) We finally gave up on the "911" in the message. -- Greg D. Moore
I'd like to briefly share our (Raleigh-Wake, NC) experience, and hopefully hear back from others with documentation of their issues.
On March 31, 2011 the 9-1-9 area code in North Carolina received an overlay that mandated 10 digit dialing for the first time. This has resulted in a significant increase in mis-dials and 9-1-1 hang-up calls for our center and others in the region. As an example, our January 2012 inbound 9-1-1 call volume was 40,669. For January 2013 it is 48,994; a 20% increase. This is also not the largest monthly increase we've seen. A similar comparison of outgoing calls rose from 19,359 to 29,477. While there may be some anticipated normal growth included, the bulk of these numbers represent increases directly related to the receipt and call-back of errant calls. As an aside, our user agencies have also been burdened due to response to hang-ups that could not be reached on call back. In our peak month more than 5,900 events were created for this activity alone. We have tried a variety of public education measures to keep the message out there, and while marginally successful, the key word is marginally. Our January 20103 hang-ups, while not the worst experienced, were higher than both our November and December 2012 totals.
See our page on Wireless E911 for an explanation of the problem, issues, and solutions.
This newspaper story explains problems in Lincoln (Neb.) with accidental 911 calls.
Nextel's Web site includes a page on how to avoid accidental 911 calls from their phones.
The U.S. Department of Justice's COPS program issued a report on 911 abuse. [Acrobat, pdf format]