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Obstacles Near Emergency Exits Speed Evacuation
BuzzSkyline writes "Despite fire codes that require emergency exits be clear of obstacles, some types of obstacles actually speed evacuation. The counterintuitive conclusion resulted from a series of experiments performed at a TV studio in Japan. Researchers from the University of Tokyo asked 50 volunteers to exit the studio through a narrow door. Video tapes of the experiments show that people made it out quickest when a pole was placed about 30 degrees to one side of the exit. The lead researcher believes an obstacle reduces jamming and friction among people in crowds by decreasing conflicts as the crowd presses toward the exit. A paper describing the research is scheduled to appear in the journal Physical Review E in September, but a preprint is available on the Physics Arxiv."
Keep your eyes open and you'll see plenty of real world applications of this principle already in place.
It's the woman on the pole that's causing the premature evacuation
I wonder if those volunteers were realistic enough.. They should have set the place on fire to see some face stomping, and in the long run maybe save lots of lives..
People act very irrationally when they are afraid of being burnt alive for some reason.
This is actually a lot more useful than much of the trivial research universities sometimes do.
Their findings can save lives...
It's shocking that anyone in this day and age still finds it surprising when scientific experiments produce counterintuitive results. So-called intuition and common sense are usually nothing more than widely held but unquestioned assumptions. That people involved in software as much as Slashdot readers and contributors should be surprised is even more absurd. We ought to know well that intuitive interfaces are really familiar interfaces; the only really intuitive interface, as some wit once remarked, is the nipple.
In any case, knowledge unverified by scientific experimentation is not knowledge at all. If there is anything surprising here, it is that we made it all the way to 2009 before someone thought to conduct experiments on a matter as important to public safety as emergency exits.
Proud member of the Weirdo-American community.
but small exit ways can lead to death like what happened at the e2 nightclub.
http://en.wikipedia.org/wiki/2003_E2_nightclub_stampede
http://www.cnn.com/2003/US/Midwest/02/18/btsc.flock/
Personally I think it would be most useful to model humans :\
The biggest issue with a real emergency situation is panic. People being squished against fences, walls and other obstacles because there's too many people behind squeezing, making it more dangerous and less efficient. Same is really for people being trampled, it's very dangerous and almost impossible to help someone being trampled back on their feet in such a crowd for the risk of not getting up yourself. I'd be very careful placing obstacles which might lead to more well-behaved behavior in scientific tests (left, right, left, right, that's so much better) but would be very danerous in a real panicking crowd.
Live today, because you never know what tomorrow brings
These guys already figured this out several years ago. (Sorry, I couldn't find a non-subscription link.)
During the pilgrimages to Mecca, one of the things that people are supposed to do is go into a large stadium and cast rocks at three pillars. Zillions of people attend this event, and there have been numerous trampling deaths at the entrance to the stadium. These guys showed that having obstructions near the entrance improves traffic flow, and so they recommended to officials in Mecca to install such obstacles there, resulting in far fewer trampling deaths near the entrance. Other means of traffic calming were used to mitigate deaths elsewhere in the stadium.
There's various places in fluid dynamics where 'obstacles' are put to improve flow aren't there? Those cone shaped things in jet engines for instance (and falcon's have similar cone shaped things in their nostrils.) Maybe this is like that.
In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)
Think of it as impedance matching.
Welcome to the Turing Tarpit, where everything is possible but nothing interesting is easy.
The building codes try to increase exit width to handle higher traffic flow. The reality, at least as suggested by the research, is similar to what landscape architects have known for generations: people walk faster on a narrow sidewalk than a broad one.
In an emergency, you hit the maximum carrying capacity of any pathway. The key to evacuating a densely occupied space is to convince people to spread out to multiple different exit points, which is confusing in an emergency situation.
I don't think anything is perfect, but when people approach a single door from a number of different angles optimum traffic flow doesn't happen.
They are not suggesting making the exit smaller, they are suggesting that an obstacle is placed further from the door to reduce the number of paths to the door and keep the number of people trying to push through the exit at any given time to a minimum. See Fig. 18 in the arXiv paper if you want to look at a diagram of this.
Interestingly enough, these results seem to have been known for a while (probably based on anecdotal evidence). I distinctly remember my fluid mechanics teacher telling our class almost exactly the same thing in 2006, explaining that a crowd headed for the exit behaved in similar ways to a fluid trying to pass through a small opening.
I came here for a good argument
Would a Russian or Italian be as effective?
The weird thing is that people who actually design stuff for crowd control have known this since at the least the 1980s. The goal is to get people ordered into efficient lines heading towards the goals and make sure people understand the process is fair and nothing is to be gained by jumping lines. For a real world example, see Heathrow's newer terminals versus its older ones, or any third world airport: if you make it easy to cheat by changing lines, and other people can see you do it, you get a mob in short order. So, keep lines narrow, and hard to switch from one to another, and people move faster. That means barriers - big ones. Just think Disneyworld, airports, good stadia.
Oh, and design the exit assembly areas so as to encourage dispersion from the final choke point at the exit: ideally, have the exit open to an amphitheater like shape so people will walk/run downhill/in various directions. Add attractors to get them away from the choke point fast: like, big sign advertising free beer 100 yards off to the side (seriously.)
Yes, there are some differences.
The extent of the difference could depend on how high the pole is mounted, e.g. how hard it is for people to step over, crawl underneath, or get around the pole.
I was at this casino minding my own business, and this guy came up to me and said, "You're gonna have to move, you're blocking a fire exit." As though if there was a fire, I wasn't gonna run.
If you're flammible and have legs, you are never blocking a fire exit.
[Mitch Hedberg]
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beware he who would deny you access to information, for in his mind he dreams himself your master
By "slight" I meant "severe." This is what's known as "sarcasm."
You also seem to misunderstand what a "pole" is. They go up and down. A horizontal "bar" is what you are thinking of. The article is NOT proposing putting bars or other actual barricades that have to be climbed over or crawled under around emergency exits... Just a simple vertical pole to encourage traffic to form a line, rather than a mob all trying to force their way through a door at once.
But place a big enough obstacle along the route and these people could refocus their navigation around one static object, rather than on the less predictable movement of others in the crowd.
This is pure speculation of course.
Unless you're a table.
Actually, the asshole in the escalade will try to get in front of everyone else. Then the asshole in the lexus will follow that.
-1 disagree is not a modifier for a reason. -1 troll, flaimbait, redundant, overrated are NOT acceptable substitutes.
Roundabouts help immensely with congestion and crashes. There were far too few before all these roundabouts were built. The accident investigators were getting quite bored.
-1 disagree is not a modifier for a reason. -1 troll, flaimbait, redundant, overrated are NOT acceptable substitutes.