« Sunspots forever | Main | India fact of the day »
The safety of elevators
Nonetheless, elevators are extraordinarily safe—far safer than cars, to say nothing of other forms of vertical transport. Escalators are scary. Statistics are elusive...but the claim, routinely advanced by elevator professionals, that elevators are ten times as safe as escalators seems to arise from fifteen-year-old numbers showing that, while there are roughly twenty times as many elevators as escalators, there are only a third more elevator accidents. An average of twenty-six people die in (or on) elevators in the United States every year, but most of these are people being paid to work on them. That may still seem like a lot, until you consider that that many die in automobiles every five hours. In New York City, home to fifty-eight thousand elevators, there are eleven billion elevator trips a year—thirty million every day—and yet hardly more than two dozen passengers get banged up enough to seek medical attention. The Otis Elevator Company, the world’s oldest and biggest elevator manufacturer, claims that its products carry the equivalent of the world’s population every five days.
And I like this passage:
Two things make tall buildings possible: the steel frame and the safety elevator. The elevator, underrated and overlooked, is to the city what paper is to reading and gunpowder is to war. Without the elevator, there would be no verticality, no density, and, without these, none of the urban advantages of energy efficiency, economic productivity, and cultural ferment.
Here is the article, interesting throughout.
Posted by Tyler Cowen on April 17, 2008 at 06:34 AM in Data Source | Permalink
Comments
best book *ever* about elevators: The Intuitionist by Colson Whitehead!
Posted by: angus at Apr 17, 2008 8:08:57 AM
Agree that elevators are a boon to mankind. But escalators = scary?
Posted by: meter at Apr 17, 2008 8:28:31 AM
And to prove your point, from today's NYT:
A 36-year-old man who was leaving a Mets game with his relatives at Shea Stadium in Queens on Tuesday night was killed after he fell over the side of an escalator and plunged more than 30 feet, the police and Mets officials said.
Posted by: Ted Craig at Apr 17, 2008 8:57:20 AM
Two things make tall buildings possible: the steel frame and...
Not really - most high-rises these days are built using a concrete central core with concrete floors cantilevering off the central core. Steel-frame high-rises, such as the WTC, are very much in the minority.
Posted by: Bartman at Apr 17, 2008 9:24:07 AM
I remember explaining the concept of "safety elevator" to my kids when they were small so they could understand why it's physically impossible for an elevator to free fall. I figured they would spend a lot of time in elevators over their lives, and they ought to have that piece of mind. I think a lot of phobias would be ameliorated if everyone understood this concept.
Posted by: M. Hodak at Apr 17, 2008 10:41:33 AM
I think a lot of phobias would be ameliorated if everyone understood this concept.
Or knew to jump a split second before a loose elevator is about to hit the ground =)
Posted by: MS at Apr 17, 2008 11:23:27 AM
"Two things make tall buildings possible: the steel frame and..."
"Not really - most high-rises these days are built using a concrete central core "
Maybe change the "k" in "make" to a "d" as in "made."
There are surely reasons that steel which was newer than concrete was used in the first skyscrapers, before concrete.
And, then people learned that the skyscraper was valuable for the "ferment" within cities. Now, they are a no-brainer.
However, had the WTC been one of the first skyscrapers and been knocked down just as telecommuting was gaining popularity, we might have completely skipped over them, and the elevator would be completely useless. Or, had the counterweight safety elevator concept not been derived to coincide with the advent of the skyscraper we might be praising the escalator. Technology history is fascinating. It doesn't seem to progress along an infallible path as it seems in hindsight.
It's also interesting that the skyscraper is an under-appreciated support for the effectiveness of cities, and the elevator is an underappreciated facilitator of the skyscraper. I don't want to go into an unappreciated business!
Posted by: Andrew at Apr 17, 2008 11:51:59 AM
I believe it is Mike Wallace's Gotham that points out that Otis's contribution was not the elevator so much as the elevator's automated safety brake.
Posted by: Thelonious_Nick at Apr 17, 2008 12:03:39 PM
I think Tyler exaggerates the case.
There are some very dense Georgian cities built in the late 18th century or early 19th. The houses are made from brick and have 4 or 5 floors. They have a basement, a ground floor and two or three upper floors. These buildings have no steel and no elevators but they still permit large cities to be built.
If we did not have the elevator and reinforcement then there would still be large, dense cities, just not perhaps ones as dense as there are now.
Posted by: Anonymous at Apr 17, 2008 12:19:07 PM
Elevators...safe?
I bet Safe T. Rider would be to differ.
Posted by: Raymond Saade at Apr 17, 2008 12:40:27 PM
How about a link for my vague memory: I recall a phrasing decades past attributed to NYTimes columnist Paul Krugman something like, "Elevators are among the most cost-effective innovations of the 20th century." Can anyone point me in the right direction? I am writing a paper, "Propinquity Matters," tying together health improvements via germ theory of disease, urbanization, and productivity growth." All ideas welcome at wpm26@georgetown.edu.
Posted by: W McGreevey at Apr 17, 2008 12:52:50 PM
Not really - most high-rises these days are built using a concrete central core with concrete floors cantilevering off the central core. Steel-frame high-rises, such as the WTC, are very much in the minority.
He isn't talking about the outside steel frame like the WTC. He is talking about reinforced concrete construction, where concrete is poured over a 'frame' of steel rebar... which IS what pretty much makes our modern high-rises possible.
There are some very dense Georgian cities built in the late 18th century or early 19th. The houses are made from brick and have 4 or 5 floors. They have a basement, a ground floor and two or three upper floors. These buildings have no steel and no elevators but they still permit large cities to be built.
But what is the historical context of these buildings? Where they pleasant places to live, or where they tenements? Certainly elevators and reenforced concrete have made high-density living a more pleasant experience, even if it is possible to do it without those things to 18th and 19th century standards of comfort.
Posted by: Rex Rhino at Apr 17, 2008 12:57:17 PM
I would just like to remind people, that in a typical year, more people in America die from elevator accidents than die from terrorist attacks! Clearly, anyone who doesn't support a multi-billion dollar War-On-Elevators hates America and Freedom!
Posted by: Rex Rhino at Apr 17, 2008 1:08:52 PM
"Or knew to jump a split second before a loose elevator is about to hit the ground =)"
I saw a 20/20 episode on falling elevators over 10 years ago that said jumping won't help at all, because at that velocity, you will still break your spine. The best way to survive is to lay flat on your back. Although, you would need to be in a large empty elevator when it broke on the 22nd floor for you to have the time and space to lay down...
Posted by: brainwarped at Apr 17, 2008 3:38:24 PM
It is hard to predict alternative technologies. Imagine a system of pneumatic tubes though high-rise building that could push people up with air. Low-tech versions of these air elevators are offered as inexpensive alternative systems for homes now. Probably they could have been developed for taller buildings if for some reason current elevator technology stumbled over key inventions, or were repressed by regulations.
And the advantage of having invested millions or billions in pneumatic tube systems for people could have been that these systems could be deployed for people and goods through cities as an alternative to current transit systems.
Another alternative technology is the one deployed at Six Flags in New Jersey (see Kingda Ka segment from Modern Marvels on YouTube). It sends people 465 feet up with vigorous hydraulic push. No cables needed.
Posted by: gregory Rehmke at Apr 17, 2008 3:39:58 PM
From driving by on the interstate the Otis elevator headquarters building in Connecticut looks like it does not contain an elevator.
Posted by: spencer at Apr 17, 2008 5:43:29 PM
I agree elevators are great. But wouldn't injuries/distance traveled be a more meaningful comparison with cars?
Posted by: Joe at Apr 17, 2008 6:46:12 PM
This is a great quote:
Loading up an empty elevator car with discarded Christmas trees, pressing the button for the top floor, then throwing in a match, so that by the time the car reaches the top it is ablaze with heat so intense that the alloy (called “babbitt”) connecting the cables to the car melts, and the car, a fireball now, plunges into the pit: this practice, apparently popular in New York City housing projects, is inadvisable.
Posted by: tomhynes at Apr 17, 2008 7:59:51 PM
This is a great quote:
Loading up an empty elevator car with discarded Christmas trees, pressing the button for the top floor, then throwing in a match, so that by the time the car reaches the top it is ablaze with heat so intense that the alloy (called “babbitt”) connecting the cables to the car melts, and the car, a fireball now, plunges into the pit: this practice, apparently popular in New York City housing projects, is inadvisable.
Posted by: tomhynes at Apr 17, 2008 8:00:14 PM
This is a great quote:
Loading up an empty elevator car with discarded Christmas trees, pressing the button for the top floor, then throwing in a match, so that by the time the car reaches the top it is ablaze with heat so intense that the alloy (called “babbitt”) connecting the cables to the car melts, and the car, a fireball now, plunges into the pit: this practice, apparently popular in New York City housing projects, is inadvisable.
Posted by: tomhynes at Apr 17, 2008 8:00:31 PM
Me:
"There are some very dense Georgian cities built in the late 18th century or early 19th. The houses are made from brick and have 4 or 5 floors. They have a basement, a ground floor and two or three upper floors. These buildings have no steel and no elevators but they still permit large cities to be built."
Rex Rhino:
"But what is the historical context of these buildings? Where they pleasant places to live, or where they tenements? Certainly elevators and reenforced concrete have made high-density living a more pleasant experience, even if it is possible to do it without those things to 18th and 19th century standards of comfort."
Well it depends on the building and its state of repair, some are awful and always have been. Some are opulent and always have been, many of the fancier parts of Bath and Chelsea in England, and Cork in Ireland are Georgian for example.
What the elevator and concrete reinforcement bring us is the ability to build _very_ densely. Walking up more than 2 flights of stairs is tedious, so people generally don't build many building with more than 4 or 5 floors. However reasonably high density can be achieved, with modern levels of comfort without elevators.
Also, in many cases concrete reinforcement is used simply because it is easier than other methods. Not because building a particular building is impossible without it. The Grand Hotel in Scarborough in England was built shortly before concrete reinforcement was invented in the 1860s. It has no reinforcement, but it is 12 floors high and has 365 rooms. This was done mainly with brickwork, there are similar buildings in the US I believe. Concrete reinforcement made this sort of stuff much easier and made building even larger building possible.
Posted by: Anonymous at Apr 18, 2008 8:46:47 AM
I was taught that the revolving door was pretty important to the development of tall buildings. The theory was that elevator shafts were basically enormous chimneys, and you had to avoid the blasts of air that would come every time somebody opened the front door.
Well, it wasn't an architecture professor who taught us that, so it could be a crock for all I know.
Posted by: David at Apr 20, 2008 4:59:09 AM
David: I was taught that the revolving door was pretty important to the development of tall buildings.
That's true.
Posted by: Anonymous at Apr 21, 2008 9:48:21 AM