Will a 911 call work for you when you need it?

Believe it or not, it has been just over 30 years that cellphones have been a feature in our daily lives. The first mainstream use began in 1984, just after what is called Enhanced 911 — or E911 — service was implemented in the Twin Cities in late 1982. (The rest of Minnesota got 911 of some type by 1987, and all of the state had E911 by the late 1990s). Unfortunately, there is an unintended but negative connection between these two events 30-plus years back.

The "enhanced" part of E911 refers to the fact that a call to 911 from a land-line phone (and only a land-line phone) can be precisely and automatically routed to the 911 dispatch center appropriate for the specific location from which the call was dialed. For example, if you dial 911 from a land-line phone in a business on the southeast corner of 50th Street and France Avenue, your call will go to the Minneapolis 911 center downtown, because you are physically in Minneapolis at that location. If you go across the street to a land-line phone in a business on the southwest corner, your 911 call will go to the Edina police dispatcher at Edina City Hall, because you are physically in Edina.

In both cases, the 911 call is presented with a data display that tells the 911 operator:

• The phone number from which you dialed.

• The specific and locatable address at which that telephone line is installed, so emergency responders can find you if you can't talk or are disoriented or don't know what address you're at.

• The name of the party or business that pays for that phone line.

• The ID of the police, fire and ambulance agencies responsible for that address.

Yes, it is true that having lots more folks out and about carrying cellphones, able to spot and report things needing attention, can be a good thing. But it is also true that having that many more cellphones "out and about" (there are now more than 300 million in the United States alone) often means that 911 centers are swamped with dozens of calls about every single (but highly visible) fire, car crash, etc., overwhelming the handful of operators on duty, often resulting in slower answering of calls, as each ringing 911 call must be presumed to be a new incident until determined to be otherwise via effective interrogation of the caller.

More important, cellular 911 calls are not necessarily routed to the 911 dispatch center appropriate to the specific location of the incident being reported. Rather, they are routed based on the location of the cell tower through which that call's radio signal was processed. In many cases that means that while you may be in Richfield while you dial 911 on your cell, the tower serving that call may be in Minneapolis, and the call may get to the wrong dispatcher, increasing the chances of response delay due to call transferring or confusion.

And most critical today, no cellular 911 call ever carries with it the locatable address of the location where you are when you dial — certainly not the apartment number or floor if you are in a multistory building.

At this point many readers are probably saying: "But my iPhone [or Android or similar] smartphone has GPS and can plot my location to within a few feet." True. Probably. (But not as accurately as you might think.) But it doesn't matter with a 911 call.

The cellular 911 network implemented in the early 2000s by the cell companies (after they were forced by the FCC to do so) was designed (necessarily and appropriately) to handle all cellphones, including the "dumb" old cellphones, the "throwaway" phones and even the "uninitialized" phones for which the bill has not been paid for months or years. Currently, this cellular 911 network can (but not always) provide only a fairly decent location for cell calls — only 12-plus seconds after answering and a manual dispatcher intervention, usually to within only a few hundred feet of accuracy, and never with any elevation (read: floor number) nor an apartment number or locatable address.

The important takeaways for all this information are as follows:

• For your home or business, I strongly recommend that you maintain or install a plain old telephone (POT) line and POT device, and not one that needs to be plugged into a wall outlet for power. Only about 40 percent of homes still have such land lines. In Minneapolis (and much of the rest of the state) you can get the cheapest CenturyLink POT line for $16.95 per month, plus tax. You can buy a simple land line phone for less than $10 at Target or Wal-Mart. And, if you're worried about those nagging solicitor calls, feel free to turn off the ringer on that new phone and rely on it only as an outgoing device.

But if you must call 911 from a cellphone:

• Know where you are (as closely as possible) when you dial (address, apartment number, highway mile marker or freeway exit number).

• Speak as clearly and calmly as possible when calling 911 on a cellphone. They have bad microphones and pick up all sorts of background interference, and if you talk real loud you become even harder to understand.

Think about that 13-year-old baby sitter at your home next weekend. Sure, she's got an iPhone, but does she know what your address is and in which community your home is located? The wrong answer to that question could be disastrous.

Keep or get a plain old telephone (POT) line in your home. Don't rely on a computer phone (like Skype or magicJack) or a cable TV phone line. They all require power, which often goes out during storms. POTs do not.