Crush Point: When large crowds assemble, is there a way to keep safe? (2011) | Hacker News Reader

Crush Point: When large crowds assemble, is there a way to keep safe? (2011)

newyorker.com

97 pointsgwern44 comments

It's a very long article, and the closest it comes to answering the question of "is there a way to keep safe" are these two sentences: "Keep your elbows akimbo, to protect your chest and give yourself enough breathing room. Don’t fight against the flow of the crowd if you’re trying to get out of it; rather, go with it, and during lulls try to work your way diagonally through the crowd to the perimeter. If you feel faint, grab on to someone, and, if you do fall, try to protect your head."

> Keep your elbows akimbo, to protect your chest and give yourself enough breathing room.

I don't understand this part. Maybe I'm misunderstanding 'akimbo' but what I see in google image search doesn't seem useful to me: https://www.google.com/search?tbm=isch&q=elbows+akimbo

"When people die in huge crowd 'stampedes', it's rarely from being trampled, it's from being crushed and suffocated (while still standing) by densely packed bodies."

https://www.reddit.com/r/todayilearned/comments/3oqcp4/til_t...

It wouldn't take much to lose that stance and have your elbows pushed inwards.

akimbo: hands on the hips and elbows turned outward

https://en.wikipedia.org/wiki/Akimbo

Yeah not sure how that would help from having your chest compressed by the crowd. That would help with saving your sides, are those the most vulnerable parts in such a case?

I'm guessing this is more along the lines of "the best you can do" than perfect. It's not like you have many other options.

That's basically the technique I use when I'm at a show in a really full pit next to the moshers. Having your elbows jut out lets them poke into people who are getting to close and lets you maintain a little bit of breathing room.

I actually keep my hands in more of the "secret service stance" rather than on my hips so that if I'm pushed suddenly I'm more likely to have my arms available for balance, or grabbing/pushing people so I don't fall. Having your arms at your side is not good when you get pushed very suddenly because usually your arms get pinned to your sides and then they're completely useless.

When things get really tight, I put my hands together in front of my chest (up by the sternum) and put my elbows against my sides. That forms a triangle and protects from the front and sides. Again, the hands are up and available so that they don't get pinned when I need them most.

Yeah, that doesn't seem useful to me either. It does seem like that's what the word 'akimbo' usually means, but I'm envisioning that they are advocating something more along the lines of this: http://creativefan.com/important/cf/2012/04/elbow-tattoos/ir...

Thank you.

The New Yorker and The Atlantic can be interesting, but with the rise of the web and not so much empty time to try to fill, one sees how they expand a little bit of information to fill all of the empty space between the ads.

Maybe take a lesson from a mosh pit too and if you see a stranger fall, pull them to their feet ASAP.

Another lesson from mosh pitting: move around, bounce off people, shove people away. Make a bubble for your to move in.

Even as a 130lbs guy, it's surprisingly easy to make a bubble if you just throw yourself at people back-first, and keep moving around roughly in a circle. Flailing your limbs also helps.

Or at least it worked when I was at a hugely packed Guns'n'Roses concert at a festival a few years ago.

The article talked about a crowd surge that bent a steel guard rail in its force. These instances seem like a different world from any mosh pit i've seen.

A crush is a situation where you cannot yourself move freely, let alone move to help pick someone up.

Having been in quite a few mildly scary crowd situations at concerts, "elbows akimbo" seems like the worst possible idea. The main force will be coming from the front and back, but your elbows will be out to the side, so people in front and back will still be able to crush you just as badly, while your arms will get trapped between the people standing beside you, giving you even less mobility than you'd otherwise have. It also seems like a good way to get your arms dislocated in a surge.

In my experience, elbows crossed in front of your chest will give you a little bit of extra breathing room, but even that doesn't do much.

Alternatively, a Reddit post describing essentially the same thing, but in fewer words, that is a good read and has some good advice on avoiding/surviving these situations.

https://np.reddit.com/r/worldnews/comments/3pcvfb/saudi_arab...

In case anyone else was like me in wondering what the outcome of the Walmart case was, it looks like they finally accepted the fine in 2014: http://www.huffingtonpost.com/2015/03/19/walmart-black-frida...

Speaking of Music Festival crowds, having worked at Love Parade a few years back where there were fatalities due to lack of crowd controls and at Tomorrowland last year, I was really impressed with the Sendrato bracelet that Tomorrowland use (http://sendrato.com/ ) which can be potentially used to determine densities of crowds in a particular area, and allow controls to be put in place before problems arise.

Here's a documentary/analysis on the circumstances that led to Germany's 2010 Love Parade disaster: https://www.youtube.com/watch?v=8y73-7lFBNE

Basically, exits were blocked off on both ends and the crowd was large enough that people trapped in the middle were crushed by enough force to led to suffocation. People attempting to move caused compression waves to ripple through the crowd which injured hundreds.

https://en.wikipedia.org/wiki/Love_Parade_disaster

The article mentions the Jamaraat Bridge which just a few months ago had it's deadliest crush yet killing over 2,000 people. https://en.wikipedia.org/wiki/2015_Mina_stampede

article is old and problem is older, research is there if you look hard enough, but until egress and crowd safety gets into building codes don't count on architects to implement the known solutions

http://arxiv.org/pdf/0906.0224v1.pdf

http://www.pmcorp.com/Portals/5/_Downloads/Simulation%20of%2...

Got a link to any cost-benefit calculations? Every new restriction made nationwide to the building code undoubtably costs society many millions or even billions of dollars. (Something like a trillion dollars of housing is built in the US each year.) I couldn't even find any news stories about people getting killed by being crushed by crowds in buildings in the US in the past couple years.

My suspicion is that building codes should be relaxed rather than tightened.

I don't think that the necessary changes apply to very many facilities at all. Maybe a few thousand buildings countrywide need to worry about crowd crushes. These sorts of crushes happen in predictable circumstances involving hundreds of people; and there are not that many concert amphitheaters. Or consider the Jamaraat Bridge - how many crushes is it, by itself, up to now?

Agree with the general line of reasoning, but I'd guess more people are crushed by small crowds in the US than large ones, exactly because the low-hanging large-crowd fruit has been picked. Would need to see some numbers. It's easy to imagine that changing a concert amphitheaters costs of order a million dollars, so you're already talking about order billions of dollars nationwide.

To be sure, less developed countries have all sorts of fixes that ought to be made.

On the other hand, the value of a life is $10-20m these days and a crush or fire can kill hundreds at a stroke, even in a small venue like the infamous Station fire. So a single incident could easily go into the billions.

I would say this issue could be resolved the same way maximum occupancy limits are established. Require buildings to establish maximum egress numbers (i.e. how big a crowd can be before a building is not allowed to open at all until the crowd is partitioned down into groups that are below the maximum egress number. This would force a pod-like crowd control solution that is observed the the NYC NYE event.

With a solution like this, Walmart would not have allowed a 2000 person line to form. Instead they would have had to partition the line into something like 20 groups of 100 people. Each group would be physically separate from the other with a buffer.

Cost of managing such a crowd grows proportionately to the size of the crowd you attract and costs are only really incurred if a crowd ever forms.

The only added cost is the work necessary for someone to calculate a maximum egress group size per building entrance. That's probably minimal extra work and likely to be proportional to the figures calculated by the fire department for getting people out safely in the event of a fire.

don't know about any calculations like that, people usually steer away to give a value to human life, and it would be very low anyway since, as you noted, there are few such incidents happening nowadays.

this is something that would only apply on the biggest buildings anyway, also, since crowd of such kind usually form at predictable times/places, it might be possible to make-do with temporary solutions, at least on entryways, if the outdoor space in front of the entry is big enough.

Actually, attaching a value to human life is a key operational feature of several federal agencies. There really isn't much way around it when you have a large enough jurisdiction and a wide enough selection of interventions. The FDA, EPA, and Department of Transportation use ~$9 million.

https://en.wikipedia.org/wiki/Value_of_life#Life_Value_in_th...

I guess that, given the difficulty we have with modelling pathfinding realistically in general, it's still a hard problem to simulate.

Nautilus published an article last year germane to this subject titled 'Want to Get Out Alive? Follow the Ants'

URL: http://nautil.us/issue/23/dominoes/want-to-get-out-alive-fol...

which suggested inside positioning of large solid round pillars at corner exits engineered to receive the funneled crowd-mass pressure and channel it around to the limited capacity exits.

With a phobia of large groups of people, I cannot even fathom how people allow themselves to get into such situations.

That mecca thing recently blew my mind, they just all crushed themselves to death and kept going.

The mecca death toll is now near 1500 people I believe. 1500!

Imagine there's a place you want to get to along with a lot of other people.

It starts as a nice queue and is pretty orderly but then some people start pushing in and trying to jump ahead in the line. Other people see this and try the same thing. If there's no good exit or crowd control then the back of the crowd slowly pushes against the front until disaster occurs.

People in the back have no idea that there is nowhere to go but they've been standing for hours and want to keep moving forward.

Yeah except for me, the sheer existence of the crowd makes my brain go "avoid avoid avoid at all costs".

I even go shopping in the middle of the night or very early morning when stores first open. I don't mind a few people but a crowd will make me turn around immediately. It is some kind of primal fear to me that shouts danger.

Apparently a great many people don't seem to have that survival instinct.

It's not necessarily a survival instinct, crowds aren't inherently bad, and they rarely result in death or injury -- what if the crowd you're avoiding is the big line for fresh water after a disaster, waiting around until the crowd dissipates may mean that supplies run out.

Reliable news sources are putting it closer to 2100: https://en.wikipedia.org/wiki/2015_Mina_stampede

"Employees asked the police for help. According to a court filing, the police responded that dealing with this crowd was 'not in their job description,' and they left."

Does anyone know if the officers initially on scene here ever faced disciplinary action?

I don't know details of this case, but in general the police don't have a duty to act in specific circumstances. They're more for our overall well being:

http://www.nytimes.com/2005/06/28/politics/justices-rule-pol...

At the risk of being "someone is wrong on the Internet"[1], I'd venture that the police did not face disciplinary action.

[1] https://xkcd.com/386/

Having had some personal experience in hugely dense crowds (like the Edinburgh Hogmanay Street Party[1]) it does indeed feel exactly like being carried along in a shoulders-deep irresistible flow of people. There were actually perceptible currents & flows, areas of turbulence around obstacles, and many other things that suggest they behave something like a fluid.

Resistance is, as explained elsewhere, extremely challenging. The sheer force of a column of people and lack of any sort of feedback means it's quite dangerous and uncomfortable. A friend and I had to rescue several people who'd fallen and were struggling to get back up, or who were being forced into obstacles. The solution was to surround them and form a sort of rugby-huddle that left enough space in the middle for them to get back up or catch their breath.

They might have better crowd management measures these recent years, but I haven't been tempted to go back on new years.

[1] http://www.edinburghfestivalcity.com/assets/000/000/264/Pack...

Update on the OSHA vs Walmart appeal case: looks like Walmart finally gave up: http://www.huffingtonpost.com/2015/03/19/walmart-black-frida...

I guess even the largest retailer on earth can't fight The Man forever.

Immediately this makes me think of nightclub fires. If you are willing to chance self-induced PTSD take a look at the uncensored videos from the Station nightclub fire. Crowded nightclubs are deathtraps.

Last time I was at a show it was particularly crowded (no seats) and I started thinking of that video as I stood there waiting for the band. I could see the 3 exits of the venue from where I was standing but I had this sinking feeling that if something happened there would be no way I'd get to any of them in time. I could feel a sense of claustrophobia rising and I had to actively put it out of my mind so I could just enjoy the show.

On Mythbusters, in their zombie myths episode, the elder duo put their crowd-crush volunteers in torso-length segments of large-diameter drainage tile, and had everyone hold their arms up above their heads while attempting to crowd-crush through a barn door.

It looked like the zombies had all gone broke in the 1920s and were wearing barrels for clothing.

But no one was apparently injured. So I guess shoppers and concertgoers could all wear crush-resistant chest armor?

I wonder if tall people have a significant advantage here.

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