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How One of the Deadliest Hajj Accidents Unfolded

nytimes.com

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Re: How One of the Deadliest Hajj Accidents Unfolded

#11

Post by gohrt »

sremani wrote: post #5
exmuslim wrote: post #4

Earlier quoted context omitted.

>Article doesn't mention any steps the organizers are making to fix it That's because they are making none. The "steps" (rituals) of Hajj have been the same for over 1400 years, there's no reason for such accidents to happen when you: Know where people are headed. When people are headed there. The number of those people. And most importantly UNLIMITED fucking ressources! Knowing that many people lost their lives beca…

I think expansion of the pathways and re-architecting the landscape to take on capacity has created conditions for "mega" stampedes, so instead of few people here and there, the stampede cascades and creates bigger chaos and takes more lives. This is what happens when expansion of capacity is done without decent safety measures in place.

Safety measures aren't enough. The requirements are impossible: In finite time window T, N people attempt pass through finite region R. N increases every year, past the point where they just don't fit.

Re: How One of the Deadliest Hajj Accidents Unfolded

#13

Post by mohsinr »

gohrt wrote: post #11
sremani wrote: post #5

Earlier quoted context omitted.

I think expansion of the pathways and re-architecting the landscape to take on capacity has created conditions for "mega" stampedes, so instead of few people here and there, the stampede cascades and creates bigger chaos and takes more lives. This is what happens when expansion of capacity is done without decent safety measures in place.

Safety measures aren't enough. The requirements are impossible: In finite time window T, N people attempt pass through finite region R. N increases every year, past the point where they just don't fit.

Number of peoples have not increased for last 10 years! https://en.wikipedia.org/wiki/Hajj#Number_of_pilgrims_per_ye...

Looks like some other factors contributed to this very unfortunate accident.

Re: How One of the Deadliest Hajj Accidents Unfolded

#14

Post by sctb »

exmuslim wrote: post #4
tantalor wrote: post #2

> caused by two large groups of pilgrims converging onto Street 204 Sounds like a traffic management problem. Article doesn't mention any steps the organizers are making to fix it. Perhaps controls at intersections?

>Article doesn't mention any steps the organizers are making to fix it That's because they are making none. The "steps" (rituals) of Hajj have been the same for over 1400 years, there's no reason for such accidents to happen when you: Know where people are headed. When people are headed there. The number of those people. And most importantly UNLIMITED fucking ressources! Knowing that many people lost their lives beca…

This comment contains both informative content and uncivil insults that the guidelines ask us not to make. Please give us the former without the latter. It's even more important around controversial topics that we comment civilly and reflectively.

https://news.ycombinator.com/newsguidelines.html

Re: How One of the Deadliest Hajj Accidents Unfolded

#15

Post by exmuslim »

sctb wrote: post #14
exmuslim wrote: post #4

Earlier quoted context omitted.

>Article doesn't mention any steps the organizers are making to fix it That's because they are making none. The "steps" (rituals) of Hajj have been the same for over 1400 years, there's no reason for such accidents to happen when you: Know where people are headed. When people are headed there. The number of those people. And most importantly UNLIMITED fucking ressources! Knowing that many people lost their lives beca…

This comment contains both informative content and uncivil insults that the guidelines ask us not to make. Please give us the former without the latter. It's even more important around controversial topics that we comment civilly and reflectively. https://news.ycombinator.com/newsguidelines.html

I apologize.

I agree.

Re: How One of the Deadliest Hajj Accidents Unfolded

#16

Post by Analemma_ »

visakanv wrote: post #9
jawns wrote: post #7

Even after reading the piece, I'm still struggling to understand the mechanics of it all. Under normal conditions, when people walking in front of you stop, you stop also so you don't bump into them. Makes sense, right? So you would think that as long as everybody obeys that simple rule of movement, this should never happen. But having been caught in a much less serious "crush" once, I know it's not that simple. In m…

I once saw a reddit comment that explained it really, really well: https://np.reddit.com/r/worldnews/comments/3pcvfb/saudi_arab...

There's also a good New Yorker article that made a lot of the same points, but in the form of a longform article, if you prefer that: http://www.newyorker.com/magazine/2011/02/07/crush-point. The bottom line is that past a certain "person density", crowds are actually governed by a lot of the same laws as fluid dynamics. When you introduce a "wall" in front of the flow, the people at the back don't even know it because they're too far away to notice. They can't know to "stop" any more than water at the back of a pipe can suddenly stop if the water ahead of it encounters an obstacle.

Re: How One of the Deadliest Hajj Accidents Unfolded

#17

Post by hexane360 »

tantalor wrote: post #2

> caused by two large groups of pilgrims converging onto Street 204 Sounds like a traffic management problem. Article doesn't mention any steps the organizers are making to fix it. Perhaps controls at intersections?

So while steps aren't being taken, several steps can be taken. Any way you can isolate one large group into several small groups, you prevent extreme pressures from building. This can be accomplished with barriers and gates to dampen waves and pressure. (As long as you don't introduce crush against these barriers)

Re: How One of the Deadliest Hajj Accidents Unfolded

#18

Post by mbrameld »

jawns wrote: post #7

Even after reading the piece, I'm still struggling to understand the mechanics of it all. Under normal conditions, when people walking in front of you stop, you stop also so you don't bump into them. Makes sense, right? So you would think that as long as everybody obeys that simple rule of movement, this should never happen. But having been caught in a much less serious "crush" once, I know it's not that simple. In m…

At a certain density a crowd of people starts behaving more like a fluid than a group of individuals.

Re: How One of the Deadliest Hajj Accidents Unfolded

#19

Post by Animats »

exmuslim wrote: post #4
tantalor wrote: post #2

> caused by two large groups of pilgrims converging onto Street 204 Sounds like a traffic management problem. Article doesn't mention any steps the organizers are making to fix it. Perhaps controls at intersections?

>Article doesn't mention any steps the organizers are making to fix it That's because they are making none. The "steps" (rituals) of Hajj have been the same for over 1400 years, there's no reason for such accidents to happen when you: Know where people are headed. When people are headed there. The number of those people. And most importantly UNLIMITED fucking ressources! Knowing that many people lost their lives beca…

The Saudis have tried to fix the problem, but not very effectively. They've built lots of tunnels and ramps. But they tend to build hard-sided walkways without escape routes. They also have too many long pathways where people can't see what's happening ahead. So anything that causes a stoppage can cause a crush.

The Mina crush may have been started by a VIP visit by the Saudi minister of defense, with a big entourage, interfering with the traffic flow. The 1990 tunnel crush was triggered by some people falling off a bridge over the tunnel exit, stopping traffic at the exit to a long tunnel.

But it's the long, inescapable walkways which are the problem. There's a good analysis at a crowd safety site.[1]

A German firm did the crowd planning for the Grand Mosque capacity upgrade in 2010, and that seems to be working well.[2] That's six miles from Mina. The Grand Mosque area is now insanely overbuilt (the giant five star hotel with giant clock tower, run by Fairmont Hotels, across from the Kaaba, looks like something from Vegas) but has much more traffic capacity.

[1] http://www.workingwithcrowds.com/2015/09/hajj-pilgrimage-mor... [2] http://spectrum.ieee.org/tech-talk/computing/software/hajj-p...

Re: How One of the Deadliest Hajj Accidents Unfolded

#20

Post by neffy »

exmuslim wrote: post #15
sctb wrote: post #14

Earlier quoted context omitted.

This comment contains both informative content and uncivil insults that the guidelines ask us not to make. Please give us the former without the latter. It's even more important around controversial topics that we comment civilly and reflectively. https://news.ycombinator.com/newsguidelines.html

I apologize. I agree.

I'm glad you said it though. The Saudi's really do have a lot to answer for.
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