Non-standard examples of standardized designs

March 23, 2005 7:45 AM

Light bulbs for public places like subways are designed with threads that run counter to ordinary light bulbs, so that the subway bulbs couldn't be stolen and used at home. I've been thinking about other examples of designing against standardization for a particular purpose (not necessarily preventing theft). Other examples might include clothes hangers in hotels, or the screws that hold together public restroom stalls. I'm trying to compile a collection of other examples. Any ideas?
posted by Jeff Howard to Technology (61 answers total)

Response by poster: I'm also a little concerned that I can't find any reference to the light bulb thing online (though there are plenty of "how many ___ does it take to screw in a lightbulb" jokes on Google). So confirmation of that particular practice would be helpful.
posted by Jeff Howard at 7:45 AM on March 23, 2005

arcade games often use "non-standard" hardware like security torx bits. That way, people can't use tools to open up the game and steal parts/cash.
posted by cosmicbandito at 7:49 AM on March 23, 2005

5-sided fire hydrant nuts?
posted by Turd Ferguson at 7:54 AM on March 23, 2005

Also, here's your source for the subway light bulbs answer.
clickee
posted by cosmicbandito at 7:54 AM on March 23, 2005

The lightbulb bit sounds like hogwash to me.

The funny screws in elevators and whatnot are called security screws. FYI
posted by Jack Karaoke at 7:55 AM on March 23, 2005

I always wondered why restroom stalls were such an attractive target for disassembly. Who are these crapper deconstructionists? And why are they not taking apart other things?
posted by stupidsexyFlanders at 8:00 AM on March 23, 2005

Some headlight assemblies on cars used to require a special tool (on ford cars I believe), the tool was star shaped.
posted by drezdn at 8:06 AM on March 23, 2005

At this point the incandescent bulbs on cars and in most stations have been replaced with florescent. Here is a story of the Port Authority using the same technique for the construction of WTC.
This googled html version of a .pdf about the 100 year anniversary mentions the opposite thread in the subways under "oddities."
posted by Duck_Lips at 8:08 AM on March 23, 2005

My favorite are the screws on happy meal toys. They are like Torx, except it's a triangle inside, not a hexagon.

The other thing that comes to mind are Do Not Duplicate keys in dorms and apartment buildings. It's not that you can't duplicate them, it's that no hardware store carries the blank keys (longer than a usual house key).

A classic example, and so not really a deviation from the standard, is the way outside doors open. In residential dwellings, doors always open in. This is so you can still open the door in a snowstorm. In a commercial building, the doors should always open out, in case of emergency, to prevent a trampling herd from pushing toward the door at once and thus, making it unable to open.

A similar example is buttons on men's and women's clothes. men's buttons (checking) are on the right side of the shirt; women's are on the left. As I understand it, this is basically to prevent a man from peeking between a girls shirt buttons as they walk down the street. Of course, the man is supposed to always walk to the left of a woman (in England, where all this came from), as this is the curb side, where splashes of nastiness might otherwise ruin a dress. The story is probably folklore, but the buttons are weirdly opposite for sure. Pants too.
posted by sdrawkcab at 8:10 AM on March 23, 2005

sdrawkcab, I think you'll find that womens buttons aren't on the opposite side to prevent guys from ogling their appendages. It dates further back, to when women had help getting dressed. If your chambermaid is right handed and is facing you, it's easier for her to have the buttons on the left.
let me google and see if I can find corroboration for that...
posted by cosmicbandito at 8:13 AM on March 23, 2005

This is a great question that will probably keep me up at night.

Hotel towels often have the name of the hotel on them so (most) people won't use them in their house. That's the only thing I can think of that hasn't already been mentioned.
posted by bondcliff at 8:14 AM on March 23, 2005

Park benches that are designed to be uncomfortable to lie down on, to discourage vagrants from sleeping on them.
posted by planetkyoto at 8:21 AM on March 23, 2005

Also on the restroom topic, I work in a public library and we have those toilet paper dispensers that let you have one small sheet at a time instead of rolls. I think this has to do with the illusion of hygeine as well as [maybe?] holding more paper than the standard roll. It's certainly less convenient for the wiper. I also think of those giant rolls of toilet paper that you see in rest stop bathrooms where the purpose is to have to change them less frequently. I'm not sure you could call the toilet paper roll "standardized." Old Apple Macintoshes used to require a very long non-standard torx T-15 wrench to be able to take them apart if you wanted to install RAM or anything. I also think of those little roundabouts in intersections in places like Seattle that are intended to slow traffic down, where "standard" is an open intersection or a four way stop, and railway gaugues that used to change at country boundaries either because of a difference in standards or a long-standing vendetta between railway agencies.
posted by jessamyn at 8:29 AM on March 23, 2005

sdrawkcab, I was always told that a man walks on the curb-side of a woman because to do otherwise is to suggest you're pimping her. The wife made me do this when we were in Spain and Mexico, after she'd been hassled about it on previously solo trips to Mexico.
posted by sohcahtoa at 8:31 AM on March 23, 2005

The nut that holds the lever for a toilet is also threaded in reverse, so that it doesn't losen as we take part in the Communist conspiracy to sap and impurify all of our precious bodily fluids.
posted by furtive at 8:33 AM on March 23, 2005

Child-resistant (and sometimes adult-resistant) caps on prescription and OTC drug bottles.
posted by googly at 8:34 AM on March 23, 2005

Those custom headphone jacks on airlines. Both the air tube style and the double mono ones.
posted by smackfu at 8:34 AM on March 23, 2005

Here in the UK, the Civil Service use ring-binders that have three rings, as opposed to our usual two. I think that this is to prevent theft of stationery. Ring-binders have lots of incompatible types, anyway: two rings here, four rings in the US, many rings in continental Europe. Not that I'm obsessed, or anything.

Again with stationery, Filofax and its competitors seem to use different methods of attaching inserts. It seems fairly obvious that this is a means of tying customers into buying expensive brand-name replacements.

I'd guess that the field of anti-competitive practice would be rife with examples of designing counter to standards. [slashdot]Not wanting to start a flamewar here,[/slashdot] but, in the field of software, Microsoft have made a healthy business out of doing just that. Allegedly.

I vaguely remember being told that, in the good old bad old days, some automobile manufacturers made positive-earthed cars, so that they'd have a monopoly on supplying parts. Don't know if that's true, though.
posted by veedubya at 8:40 AM on March 23, 2005

I work in a public library and we have those toilet paper dispensers that let you have one small sheet at a time instead of rolls.

And if they're like the ones I've encountered on occasion, they're waxed. Ugh.

There are tri-wing versions of Philips heads; they're a security measure screw.

There are a half-dozen or so compressed-air coupling mechanisms. I think this is to force you into a single manufacturer's product. Hell, same thing applies to staple gun staples. Really very irritating, that.

Lots of electronic equipment has proprietary connectors. Garmin GPSes use their own type of socket.

Hell, there are even a few types of car cigarette lighter sizes... and that despite there being a ton of aftermarket equipment that would like there to be a single size.
posted by five fresh fish at 8:48 AM on March 23, 2005

Mr Chrysler, why did you steal 40,000 hotel coat hangers, knowing as you must have that hotel coat hangers are designed to be useless outside hotel wardrobes?
posted by kokogiak at 8:49 AM on March 23, 2005

Clocks with Roman numerals usually have the number 4 represented by IIII, rather than the standard IV. Supposedly, this is for asthetic reasons.
posted by veedubya at 8:49 AM on March 23, 2005

Internet Explorer's creative interpretation of various web standards helps maintain their hegemony. Web designers have to decide if their page will be correct, or if it will look right on the browser that 90% of the world uses.
posted by Capn at 8:53 AM on March 23, 2005

Most fittings designed to carry hydrogen under any pressure are reverse threaded to prevent anyone trying to use non-H2 approved fittings instead.
posted by thatwhichfalls at 8:55 AM on March 23, 2005

Some OEMs sell computers containing powersupplies that appear to have standard molex connectors, but the wires are rearranged.
posted by Eamon at 9:11 AM on March 23, 2005

Propane tanks used to be reverse threaded, too, thatwhichfalls. They're not anymore, though.
posted by MrMoonPie at 9:14 AM on March 23, 2005

This principle seems to be very much at work in the design of jailhouse toilets and other penal fixtures. There is also a "suicide resistant" model.

Also, sdrawkcab, if the placement of women's buttons were to prevent people on their left from looking in their shirts, the buttons would be on the right-hand side of the shirt rather than the left.
posted by mokujin at 9:15 AM on March 23, 2005

Oh, and on my old 82 Corolla/Tercel, the cigarette lighter's polarity was the opposite of that of most accessories. I quickly learned to cut and reverse the wires of anything (like a radar detector) I wanted to plug in.
posted by MrMoonPie at 9:16 AM on March 23, 2005

When unleaded gas was first introduced, cars that required it had narrower gas tank filling tubes so they couldn't take leaded gas -- nozzles which were, at that time, standard -- because it was damaging to catalytic converters. Manufacturers had to make narrower pump nozzles to fit these new gas tank
posted by jessamyn at 9:16 AM on March 23, 2005

- Security lugnuts on car wheels -- the kinds that have a tapered cylindrical outside and serpentine trench that accommodates a special tool, rather than a hex shape.

- The left (or is it right?) pedal spindle on a bike is always reverse-threaded. This is for functional reasons, to prevent it from unscrewing during riding. Bikes are rife with weird standards, in fact: There are two common kinds of bottom-bracket thread patterns (English & Italian), a rarer kind (French--there's always a weird French standard for things on bikes), and the very rare Swiss. Bike tire sizes are a black hole of confusion, where 1.25" does not equal 1 1/4". Sheldon Brown has a vast compendium of this minutia.

- The USA is still using the imperial measurement system. Us and who else? Kenya? This has to be the biggest example of an idiosyncratic standard in the world.

- Paper weights in the USA are confusing even for the imperial system. The Chicago Manual has a good writeup on this.

- I don't know much about this, but I understand there's a special (and now obselete) pipe size for gas heating equipment in Texas.
posted by adamrice at 9:20 AM on March 23, 2005

Considering in other countries lightbulbs use bayonet sockets, I question why, for the purpose of loss prevention, the subways didn't go to those?

Quicker production, cheaper, and ready for sale.
posted by shepd at 9:23 AM on March 23, 2005

To elaborate on what veedubya said, the Jeppesen aeronautical charts (used by most airlines) have a proprietary 7-ring binder system (see pic). I've never been able to find a binder at office supply stores that will handle these pages, so ostensibly it's so that you buy Jeppesen's pricey line of binders.
posted by rolypolyman at 9:51 AM on March 23, 2005

MrMoonPie, couldn't you have swapped the wires over on the lighter socket? Was there some reason that the lighter itself wouldn't get hot with the polarity reversed?
posted by veedubya at 10:18 AM on March 23, 2005

I think this has to do with the illusion of hygeine as well as [maybe?] holding more paper than the standard roll.

I read an article in the Globe about this a few years ago. Basically, those one-at-a-time dispensers encourage you to use less. The article was about how a local food chain went from standard napkin dispensers to packs that make you take one at a time in a time-consuming, deliberate fashion. The result was fewer unused napkins being thrown away and tens of thousands in savings. The article mentioned that restrooms have been using this method for years, and the cost was secondary-- toilets clog less frequently if people are discouraged from using huge wads of paper.
posted by Mayor Curley at 10:26 AM on March 23, 2005

Each camera manufacturer has their own standard for SLR lens mounts, for the most part.
posted by bshort at 10:37 AM on March 23, 2005

Train tracks in Australia were built by different companies in different states. Each company used a different gauge (width) of rails, ensuring that you'd have to change trains (and tracks) at every border. They've finally fixed the problem.

The buttons on the left/right for means/women's shirts has many different proposed explanations. I think that the chambermaid explanation is the most likely.

Different pinball machine manufacturers used different styles of flipper, score reel, and score wheel assemblies, resulting in a need to carry parts for all 3 major manufacturers. This being despite the fact that all those parts ended up performing exactly the same function.

I've heard that BMWs require specialized tools to work on the in-cabin parts.
posted by Four Flavors at 10:45 AM on March 23, 2005

A lot of weedwhackers/brushcutters have reversed threads on the heads. I assume it's done for the same reason adamrice noted about bike pedals.
posted by joaquim at 11:04 AM on March 23, 2005

trharlan, the left-hand screws on bicycles (on pedals, for example) is so that the prevailing motion doesn't tend to loosen the threads. Chrysler did this on some vehicle lugnuts in the 60's, and most spindle nuts (on the non-drive axle) are still like that.
posted by notsnot at 11:04 AM on March 23, 2005

Five-sided nut to turn on a fire hydrant.
posted by buxtonbluecat at 11:44 AM on March 23, 2005

My understanding is that the original typewriters were designed with the letters arranged in alphabetical order but early typists regularly jammed the keys by typing too fast, so the QWERTY keyboard was designed to slow typists down. This would be a case of the redesign supplanting the earlier standard.

I feel the same fascination for this topic as I have for the notion that maps, dictionaries and even books of logarithmic tables (back when ships needed them to navigate) supposedly had deliberate inaccuracies in order to find copyright infringers. I've always wondered if some crew starved to death because of they got unlucky and relied on some of the 'gotcha' information....
posted by kimota at 12:05 PM on March 23, 2005

Train tracks in Australia were built by different companies in different states. Each company used a different gauge (width) of rails, ensuring that you'd have to change trains (and tracks) at every border.

There's something similar in American history. At least one historian attests that a factor in the Confederate states' defeat in the American Civil War was due to their differing gauges. Meanwhile, the Union standardized on one gauge. The result was faster troop transports and more resilient supply lines. From Snopes:

Nonetheless, despite this commonality of equipment, well into the 19th century the U.S. still did not have one "standard" railroad gauge. At the time of the Civil War, even though nearly all of the Confederacy's railroad equipment had came from the North or from Britain (of the 470 locomotives built in the U.S. in 1860, for example, only 19 were manufactured in the South), 113 different railroad companies in the Confederacy operated on three different gauges of track. This lack of standardization was, as historian James McPherson points out, one of the many reasons the Union was able to finally vanquish the Confederacy militarily.

posted by jbrjake at 12:28 PM on March 23, 2005

Regarding the buttons, the most convincing explanation I'd ever heard was an expansion of cosmicbandito's point...that initially, all buttons were arranged like women's buttons still are, because anyone who could afford clothing with buttons was being dressed by someone else, and that someone else was assumed to be right-handed. Especially since you'd be talking about big buttons, and big plackets, that would make sense.

The story I've heard said that men changed the direction of their plackets when ceremonial swords became much more fashionable, since if you wear your scabbard on your left hip and draw the sword with your right, your hilt would be likely to catch on the edge of the placket. Switching the direction of the buttons means that you're drawing the sword "with" the placket, across a smooth, broad stretch of cloth. (Think of 17th/18th century coats, with the really big, broadly spaced double-vested buttons, and it kind of makes sense. With the modern inch-wide placket, it wouldn't really matter.)

Of course, that could all be entirely apocryphal, but it made sense to me.
posted by LairBob at 12:47 PM on March 23, 2005

the QWERTY keyboard was designed to slow typists down

More precisely, so that certain two-key combinations were far apart. Analysis of letter combination stats doesn't immediately support me here, but here's a quick explanation. Note that two-finger combinations were not sufficiently considered in Dvorak, so that the alternate key layout is not, in fact, faster.

deliberate inaccuracies

Usually included fake place names in maps. Phone books would include fake entries. Unfortunately for the makers, phone books were deemed uncopyrightable, though that may change.

Pardon the minor derail.
posted by NickDouglas at 12:48 PM on March 23, 2005

<sub>Now that the cold meds are clearly kicking in, I'm going to go lie down before I say "makes sense" one more time.

Whoops.</sub>
posted by LairBob at 12:50 PM on March 23, 2005

Allied agents in WWII used to smuggle tiny bits of microfilm containing valuable info in their big hollow coat buttons: the top of the button unscrewed like a jar lid. Well, the Germans caught on, and to foil them, the Allies reversed the threads on the button to left-hand. It worked; the Germans eventually stopped fondling their buttons since they weren't unscrewing anymore.
posted by Specklet at 1:28 PM on March 23, 2005

The U.S. and it's allies use an 81mm mortar system for mid-range indirect fire support. After the introduction of the 81mm system, Russia came out with an 82mm mortar system, capable of using not only the 82mm mortar ammunition designed for it, but also the 81mm mortar rounds the U.S. produces.

I'm sure there are other examples of military weapon systems designed to accept someone else's ammo without the enemy's weapon systems being able to accept theirs.
posted by cactus at 1:30 PM on March 23, 2005

The "fire hydrant" example reminded me of a math teacher I used work with--he used to love examples of this. He'd always give bonus questions like "Why do fire hydrants have five-sided bolts?", and "Why are manhole covers round?" (Because a circle is just about the only shape that can't fall into itself.)

I've tried to dig up some of his other questions, but that was like 15 years ago...
posted by LairBob at 1:40 PM on March 23, 2005

The designs on US paper currency (and presumably bills in other nations) are purposefully complex to thwart counterfeiters.

Spam email titles are purposefully odd in order to make you curious about their contents.

Some TV shows last slightly longer than their official length (i.e. ending at 10:01 instead of 10:00) in order to thwart TIVOs and channel surfers.
posted by grumblebee at 3:48 PM on March 23, 2005

The list is beyond endless...

Apple's attempt to corner the music file format. Microsoft's and their attempt to corner the video file format. Sony memory stick. Proprietary battery packs of all kinds in all kinds of hardware. Intel regularly changes their CPU sockets simply to break computability with new processors (BX chipset rules!!!). Compaq hot swap drive sleds.
posted by Chuckles at 4:16 PM on March 23, 2005

Some TV shows last slightly longer than their official length (i.e. ending at 10:01 instead of 10:00) in order to thwart TIVOs and channel surfers.

I'm not an expert on this but I have always reasoned that TBS's shows started and ended five minutes past the half hours because viewers would have already missed the first part of other channels's shows and thus be forced to remain on TBS. Also it's interesting that Leno and Letterman always begin at exactly 11:37pm. I guess they reached some sort of agreement?
posted by foraneagle2 at 5:29 PM on March 23, 2005

Response by poster: Wow, thanks everyone for the answers. Lots of paths that I hadn't even considered. "Safety" is an important one that keeps coming up. After my younger brother accidently put diesel fuel in his car, I remember thinking that diesel nozzles and diesel tank openings should be some shape that isn't compatible with regular fuel openings. Or maybe just a larger diameter.
posted by Jeff Howard at 6:32 PM on March 23, 2005

My understanding is that gents should walk on the street side of their ladies so that the slops aimed at the gutter from upstairs windows will be less likely to land on said ladies. Also, so that passing carriages splashing the gutters out will dampen the gents, not the ladies.

The button-side thing is not universal. It's reversed in China.

Harley-Davidsons used to be rife with proprietary hardware. Instead of the standard 1/4-20 or 1/4-28 screws that the rest of the US used, H-D used 1/4-24. Nobody had those screws but your Harley dealer.

Bridgeport milling machines used special ball bearings on the table spindles. As I recall, they were an inch dimension on the OD, and a metric size on the ID, but I may have that backward. At any rate, they were not the standard metric-sized bearing that you could buy anywhere for a couple of bucks, and you had to give Bridgeport a lot more for bearings that fit.
posted by Kirth Gerson at 6:43 PM on March 23, 2005

MrMoonPie, couldn't you have swapped the wires over on the lighter socket? Was there some reason that the lighter itself wouldn't get hot with the polarity reversed?

The reason is, there's only one wire going to the cigarette lighter. The car's chassis us used for the second wire, and if it's hooked up to the positive terminal of the battery, you're getting positive on that side of the connection, whether you like it or not.

What he really needed was an adapter that swaps 'em round.
posted by kindall at 6:46 PM on March 23, 2005

Another light bulb example. Commercial florescent bulbs have a single broad nipple at each end for the electrical contact, rather than the double-pins on those intended for home use. This is apparently to discourage theft.
posted by Good Brain at 8:38 PM on March 23, 2005

ISO paper sizes and U.S. deviations, yet another topic I'm somewhat ashamed to find so fascinating.
posted by fatllama at 8:45 PM on March 23, 2005

re: florescent bulbs -- my guess is that it's because the second pins are unnecessary. At any given time, the tubes use only one set of pins. During startup, one pair get a momentary but extremely high-voltage zap to initiate conduction; the second pair are then used to maintain conduction. I should imagine a commercial system might very well have circuitry that allows both to occur on the same wire.
posted by five fresh fish at 10:38 PM on March 23, 2005

The street-side water shut-off for a previous home was pentagonal, like the fire hydrants mentioned above.
posted by NortonDC at 12:32 AM on March 24, 2005

kindall, now I feel stupid, considering as how I'd previously mentioned positive-earthed cars.
posted by veedubya at 3:45 AM on March 24, 2005

I feel the same fascination for this topic as I have for the notion that maps, dictionaries and even books of logarithmic tables (back when ships needed them to navigate) supposedly had deliberate inaccuracies in order to find copyright infringers.

As noted above, this is common with maps. It's also extremely common in occult circles; 'blinds' are often used to track copyright (you would be astonished at the amount of outright theft in most publications in the field), track versions, etc. Pat Zalewski is famous for doing this.
posted by dirtynumbangelboy at 7:57 AM on March 24, 2005

Also with the subway (at least Toronto's), the voltage is at non-standard levels so that people can neither steal components nor plug something in and steal power while in the subway car.
posted by heatherann at 10:55 AM on March 24, 2005

The other thing with the single pins is they are easier to install. This is important when your dealing with a 8' tube at the top of a 20' ladder.
posted by Mitheral at 2:24 PM on March 24, 2005

Jeff Howard: I remember thinking that diesel nozzles and diesel tank openings should be some shape that isn't compatible with regular fuel openings. Or maybe just a larger diameter.

This already happens with low (for cars) verses high (for highway tractors) flow pumps. The nozzle on a high flow pump won't fit into a car's fill pipe.

This didn't stop a guy from attempting to fill his rabbit at the tractor pump at my sister's service station a few years back. Man a lot of diesel can come out of a hose a couple inches in diameter in a short period of time.
posted by Mitheral at 2:29 PM on March 24, 2005