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The Straight Dope

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The questions you deal with in your column are usually pretty cosmic, but maybe as a change of pace you wouldn't mind taking a whack at the following shallow topics: (1) What are those red or orange balloon things you see on high-voltage utility wires when you're driving out in the country? I've heard several theories, but none seems to hold up under critical examination. (2) Is there any rhyme or reason to the assignment of area codes? Why aren't numerically sequential codes given to geographically adjacent areas? When I call Mom in area code 414 (eastern Wisconsin) but get San Francisco (415), it seems like a plot to separate me from more of my money. --John Reindl, Madison, Wisconsin

Johnny, Johnny, Johnny. (Kinda Garboesque, ain't it?) The telephone company is your friend. One of the reasons area codes are assigned the way they are is precisely to prevent you from dialing the wrong code by mistake. But let's take your questions in order.

(1) The "balloon things" are aircraft warning markers intended to prevent some joker in a Piper Cub from clotheslining himself. You see them near airports with a lot of general aviation traffic--i.e., low-flying small planes. Typically the markers are fiberglass spheres tricked out in some high-visibility color, but occasionally you see other designs as well. They've definitely inspired their share of carrot-brained theorizing. I knew a guy who said the purpose of the balloons was to "scare away the birds." Tragic evidence of the impact of the thinning ozone layer.

(2) The assignment of area codes may seem random or even malevolent to you, John, but this merely reflects your troubled inner being. Actually it's pretty sensible. The North American Numbering Plan, of which the area codes are a part, was worked out in the late 1940s to ensure standardized numbering nationwide, helping to make direct-dial long distance possible. (Prior to that time you had to go through an operator.)

On the rotary-dial phones then in use, dialing a nine took a lot longer than dialing a one, which bugged consumers and tied up expensive switching equipment. So AT&T assigned "low dial pull" numbers to the markets with the most telephones and thus presumably the highest number of incoming long-distance calls. New York got 212, Chicago 312, LA 213, Detroit 313, Dallas 214, and so on.

Some area codes aren't so easy to explain. Boston got 617 while comparatively rural western Massachusetts got 413; Washington, D.C., got 202. (Zero, remember, has the highest dial-pull of all.) Whether these anomalies represented some smoldering vendetta against the eastern seaboard we may never know; the people responsible have long since retired.

The issue of dial pulls became academic with the introduction of Touch-Tone phones in the early 1960s. Since then the guiding principle behind the assignment of new area codes has been to make the new number as different as possible from the adjacent old numbers in order to avoid confusion. That's why the split of New York's 212 produced 718, LA's 213 begat 818, and Chicago's 312 will soon be joined by 708. The drawback of this approach is that when you do make a mistake it's a lulu, giving you San Francisco, for example, when you were trying to dial Milwaukee. But the phone company will readily delete such goofs from your bill.

As far as Ma Bell is concerned, the real problem with assigning area codes is that it's running out of numbers to assign. At the moment the switching system requires that the middle digit in each code be a one or a zero, which means there are only 152 numbers available. Of these, all but 15 are already spoken for. To get around this limitation, phone companies around the country have been implementing "Dial-1" service, which requires you to dial one at the start of any direct-dial long-distance call. Eventually this will permit the use of additional digits in the middle position, giving us a total of 792 potential codes, which ought to hold us for a while. Look for it by 1995.

Art accompanying story in printed newspaper (not available in this archive): illustration/Slug Signorino.

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