Yamanote Line Platform Gates

[bill937ca]

 

[CaptOblivious]

dislike.

[westfalen]

As a train driver coming into a crowded platform I could appreciate them but as a railfan I don't know. I'll see them in person in a couple of weeks.

[bill937ca]

Platform barriers slow to spread

 

http://search.japantimes.co.jp/member/member.html?mode=getarticle&file=nn20100829a7.html

[KenS]

As a modeler, I hate the idea of platform gates in general (so much extra work, and they restrict the types of trains a station can support), and as a railfan I worry that full-height ones will severely limit the kinds of photos/videos we'll see in the future.

 

There's also a real-world version of the flexibility problem: you need identical trains for gates to work, and "identical" isn't an adjective readily applied in Japan.  In fact, it's probably not true most places in the long run. Even on a subway there may be several generations of cars in use simultaneously, and at a main line station there are likely to be different trains serving different uses (local, suburban, and regional inter-city) with different passenger loadings and ingress/egress traffic requirements.  You could solve this by standardizing door placement, but that will need to be optimized for the busier commuter trains, which will have a negative effect on suburban/regional train capacity; there's a reason long-distance trains have doors at the ends: more seats in the middle.

 

And lack of flexibility has a cost.  The Yamanote line added six-door cars when it needed more capacity.  JR East has said that reduced traffic due to the economic downturn removed the need for those, so removing them to allow gates to be added was acceptable.  But what happens ten years down the road when they need more capacity?  Replace every train and rebuild all of the gates simultaneously?  That sounds very expensive.

 

But those concerns aside, I have more mixed thoughts.  There are two reasons I've heard for platform gates: suicide prevention and safety (against people accidentally falling on the tracks due to crowding, vision problems, or intoxication).

 

You can't really stop someone intent on killing themselves.  But gates (full height, not the Yamanote-style low gates) remove a situation where a depressed individual might give in to an impulse.  Even low gates raise the difficulty, which would likely dissuade some individuals. I tend to doubt that the number of those justifies the extra cost, as well as thinking that there may be better ways to achieve that goal with the same money (help line staffing; station improvents to make them less dark and gloomy; track-obstruction and end-of-platform pressure sensors, although many Japanese stations already have those; etc.).  That the Yamanote line has low gates despite its reputation for suicides tends to make me think that JRs planners don't see gates as a cost-effective suicide-prevention solution (of course corporate cost-effectiveness isn't the same as the social value of a cost being justified).

 

Saftety is a harder issue.  Given the rush-hour crowding that takes place in some of the urban Japanese stations, it's hard to say this isn't a good idea, at least in theory.  Of course it's not clear how well these gates will work when people are jammed up against the doors trying to wedge into a packed train.  What happens to that crowd when the train doors close, but they can't back up past the platform gates?  Do they just remain there, unable to move to the side or back?  I can actually see where the gates could increase risk in overcrowded conditions by keeping peope at the edge of the platform as the train pulls out.

 

In the end, I'm skeptical that platform gates are really a good idea.  There are certainly plenty of situations where they will provide an advantage. But they aren't risk free. And although you can't put a cost on a life, it's a fundamental of civil engineering that you must put a cost on improvements justified only on safety.  It's often a high cost: many structures have significant safety margins against unlikely risks, but at some point you have to say that the added safety doesn't justify the cost increase.  This just seems like spending a lot of money, directly and indirectly in limitations on future train size/design, to achieve a statistically small improvement.

 

And all that leave me thinking that they're probably not a good idea.  But I'm not absolutely convinced.  The Yamanote line gates will at least provide a large-scale test of the concept. I'm aware that there are already several other stations in Tokyo with gates, but the sheer volume of passengers affected once all of the Yamanote stations are equipped will be a much larger test, I believe. And it's a line that will need its trains replaced in the next decade (due to the current ones wearing out, if nothing else), so it should test the long-term effectiveness and cost also. So it does seem like a good test case for JR.  If it's going to work anywhere, it should work here. And this line is likely to highlight any problems as well.

[Guest ___]

That delay between the platform gate and the train doors opening one would think would cause an increase in load and unload times. Considering a two second delay in train operations ripples through out the entire network, I'd hate be the scheduler who had to build in gaps to either increase or decrease load times.

 

[railzilla]

AFAIK Platform screen doors where first used in Singapores MRT and there only in the underground stations. Main reason for the platform doors was the need for air conditioning in tunnel stations. If safety where the main reason the elevated station would needed platform doors from the beginning too.

There are even fully automated metro system which have no doors. There might be a delay for opening both train and platform doors, but thanks to the platform doors trains can run a higher speed while approaching or leaving a station. So the doors might even have a small benefit in regards of speed.

Personally i am more pro than contra for platform doors. Wagon length and door spacing needs to be standardized but thats not an impossible task. I saw the remains of a rail suicide for twice already and both cases where in a station next to a platform. So maybe platform doors are a good way to reduce rail suicides.

[westfalen]

That delay between the platform gate and the train doors opening one would think would cause an increase in load and unload times. Considering a two second delay in train operations ripples through out the entire network, I'd hate be the scheduler who had to build in gaps to either increase or decrease load times.

You may hav a point there. A few years ago in Brisbane they decided after someone got caught in the closing doors of a train to have an automatic announcement saying 'doors closing, please stand clear'. Until the trains were modified the train crew had to make the announcement themselves then close the doors, the extra few seconds made each train several minutes late over the course of its run.

[bikkuri bahn]

I'm no expert on the psychology of those contemplating suicide, but my understanding is that even little disincentives, such as mirrors or special lighting, often discourage potential suicides.  A half-height barrier may not deter the most determined or athletic, but most cases, I think, presented by that obstacle, will either rethink their actions, or do the deed elsewhere.  Anyway, the barriers also serve to prevent people from being shoved (intentionally or otherwise) unto the tracks, or simply from falling onto them due to platform crowding, being drunk, or being in a wheelchair/pram.

[Guest ___]

AFAIK Platform screen doors where first used in Singapores MRT and there only in the underground stations. Main reason for the platform doors was the need for air conditioning in tunnel stations. If safety where the main reason the elevated station would needed platform doors from the beginning too.

There are even fully automated metro system which have no doors. There might be a delay for opening both train and platform doors, but thanks to the platform doors trains can run a higher speed while approaching or leaving a station. So the doors might even have a small benefit in regards of speed.

Personally i am more pro than contra for platform doors. Wagon length and door spacing needs to be standardized but thats not an impossible task. I saw the remains of a rail suicide for twice already and both cases where in a station next to a platform. So maybe platform doors are a good way to reduce rail suicides.

 

Playing devil's advocate here. While SBS installed the doors first on the North East MRT line, and SMRT added them later to existing stations, were only on the underground stations to keep them cool as already stated. There is yet to be any barriers on the above ground stations and I recall as reported in the Straits Times that the Ministry of Transport stated that there are no plans to add them to any above ground stations on either SBS or SMRT lines. I do not foresee trains arriving at stations faster with the advent of the barriers on any of the JR lines. Braking is already optimized for the fasting possible deceleration while maintaining maximum passenger comfort. I think they're already at that threshold.

 

I also don't foresee platform doors as a way to prevent suicides. As stated, it's not hard to climb over them. In fact here in DC not too long ago, NHK did a report on them, showing how easy it is to get around them, and how much it will compound the issues of loose clothing items such as mufflers to get stuck in them. This is already a winter issue in Japan as it it. If someone wants to die by train hard enough, it's not that hard to do, especially with all the at-grades there are on both the JR and private lines.

[disturbman]

There's also a real-world version of the flexibility problem: you need identical trains for gates to work, and "identical" isn't an adjective readily applied in Japan.  In fact, it's probably not true most places in the long run. Even on a subway there may be several generations of cars in use simultaneously, and at a main line station there are likely to be different trains serving different uses (local, suburban, and regional inter-city) with different passenger loadings and ingress/egress traffic requirements.  You could solve this by standardizing door placement, but that will need to be optimized for the busier commuter trains, which will have a negative effect on suburban/regional train capacity; there's a reason long-distance trains have doors at the ends: more seats in the middle.

 

Well, usually the lines being equiped with PSDs only see one type of train servicing them and usualy the commuter/underground stock are standardized. I don't see that argument as a problem. If you need to run a long distance train on those line you can also adapt the door patterns on the IC stock to the position of the PSD and not open everyone of them when the train stops. :)

 

And lack of flexibility has a cost.  The Yamanote line added six-door cars when it needed more capacity.  JR East has said that reduced traffic due to the economic downturn removed the need for those, so removing them to allow gates to be added was acceptable.  But what happens ten years down the road when they need more capacity?  Replace every train and rebuild all of the gates simultaneously?  That sounds very expensive.

 

Well I don't think a 6-door standee only car as a perenial solution. If there is such overload problem then the network needs to be expand in a way that can offer some comfort to users. Sure it will be more expensive in a long run but also a lot more future oriented. Anyway, since Japan is on the verge of an impressive population shrinking the lines patronage will more likely shrink as a result in the not so distant future.

 

You can't really stop someone intent on killing themselves.  But gates (full height, not the Yamanote-style low gates) remove a situation where a depressed individual might give in to an impulse.  Even low gates raise the difficulty, which would likely dissuade some individuals. I tend to doubt that the number of those justifies the extra cost, as well as thinking that there may be better ways to achieve that goal with the same money (help line staffing; station improvents to make them less dark and gloomy; track-obstruction and end-of-platform pressure sensors, although many Japanese stations already have those; etc.).  That the Yamanote line has low gates despite its reputation for suicides tends to make me think that JRs planners don't see gates as a cost-effective suicide-prevention solution (of course corporate cost-effectiveness isn't the same as the social value of a cost being justified).

 

Well, you don't think but there is studies about that kind of stuff and (from what I've heard) they proved your point wrong. Even a low barrier type like on the Yamanote as been proven enough to deter most of the suicide attempts. :)

 

Safety is a harder issue.  Given the rush-hour crowding that takes place in some of the urban Japanese stations, it's hard to say this isn't a good idea, at least in theory.  Of course it's not clear how well these gates will work when people are jammed up against the doors trying to wedge into a packed train.  What happens to that crowd when the train doors close, but they can't back up past the platform gates?  Do they just remain there, unable to move to the side or back?  I can actually see where the gates could increase risk in overcrowded conditions by keeping peope at the edge of the platform as the train pulls out.

 

You really think nobody thought about that? ;) That kind of PSD is equiped this system that don't allow doors to close on someone or to let someone be trapped between the train and the PSD. :)

 

 

Well, PSD works quite fine around the world. I don't see how it could be more a bad idea here. ;) The real problem with PSDs are the slight increase of dwelling time they induce.

[Guest ___]

All the gates do, is just turn a would be jumper in to SEP. It still doesn't solve the cause of the problem to begin with. The gates only goes to negate the larger social issue to someone else, probably another train station or line without the gates. It will work about as well as the women only cars to combat gropers. Maybe JR needs to look to to do more of what the military claims to do here and look harder at prevention in the first place. JR is a stakeholder in all this and had to invest billions of yen in gates, and even go as far to install "soothing anti-suicide blue lighting" in an attempt to protect its profits and reduce delays brought on by jumpers. That didn't work either. Personally, the gates won't affect me any as how I shoot images, I just see half height barriers as a waste of money. Full-height I see the value to, but the half height, no way. Some one wants to off themselves that bad, the gates do nothing to stop them.

[disturbman]

Yeah for sure they will still have to deal with suicides but their numbers should go down as most people won't have the necessary courage/force/whatever to jump them. Half-height is already pretty high and maybe station can't handle full-height (but maybe two-third height) PSD due to structural deficiency.

 

But Aaron excuse me, it's not JR's (or any subway/rail company) role to do suicide prevention. Suicide is a general problem. Prevention has to be done at a societal level and be based on some psychological and social networks.

[David]

disturbman is right in that JR East isn't the one creating the problem, they're just one of several convenient outlets for the result.

 

I think we might be underestimating how effective the "half height" barriers are. In addition to facts already mentioned about deterrence, I think they make it a lot harder for the average Japanese person to successfully commit suicide. The first part is look at the height of the barrier next to an actual person - while for some of us tall westerners those barriers must only be waste high, for many Japanese they'ed need to climb over the barrier.

 

Climbing over might not seem to be a big factor in preventing a successful suicide, but from a Toronto perspective I think it is. We get a number of suicides by TTC subway (averages about 1 failed attempt and 1 successful per month ), and a big factor in success is that the smart jumpers do it near the end of the platform where the car enters the station - those that do so from the middle and especially the wrong end of the platform can find themselves sitting on the tracks staring at the driver of a stopped car. I think that the time it takes for someone to climb over the barrier (unless they've really planned out some kind of running start) adds critical reaction time for the driver and station staff to either stop them before they get on the tracks, or bring the train to an emergency stop before it hits them.