Is too much safety stuff dangerous?

[ComUtoR]

Sorry, I shouldn't have used that bit of slang.

No worries, just never heard it before.

 

[atraindriver]

<deleted>

 

[AndrewE]

No I don't think so. People do not drive on the road more recklessly because [they] know that their car has an airbag to save them in the event of a crash so I doubt anyone would drive a train dangerously and expect safely equipment to save them. It's not safe to be too reliant on anything

I'm afraid I believe the opposite is true in the case of motorists. Not necessarily airbags, but front-wheel drive, better braking and all sorts of other things mean that lots of people drive as though they were invincible, when if they drove a Morris Minor or more powerful rear-wheel drive car in the same way they wouldn't last a week.
Train driving, however, is treated as a responsible professional job (with lots of different sorts of oversight and reporting) and is therefore not treated as a lark, unlike boy racers on the roads. The recruitment is rather more stringent than passing a driving test too. I very much doubt that I could get through it (or could have, even as a 20-year old. I suspect it was a rather different process then though...)

 

[ComUtoR]

I don't.

There's a (perhaps surprising) number of acronyms and terms which are operator or area specific, and I quite often read terminology here which is clearly being used in the belief that it's well known and will be understood by everyone, but which mean nothing to me.

KVB - Contrôle de vitesse par balises

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

 

[atraindriver]

<deleted>

 

[ComUtoR]

On the wiki page it states

Contrôle" is abbreviated to "K", to distinguish it from "Commande

The closest equivalent UK system is TVM, which is used by HS1 but that will all change when we move to ETCS

 

[silverfoxcc]

To mods, feel free to amend/delete if warranted

With the advance of digital systems, ( and i am only throwing this out as a suggestion,so willing to get actual reasons why it cannot be done rather than a NO) how easy would it be to put a screen in the cab that gives advance warnings of Temp speed restrictions. ie a sender attached to a sleeper that can easily be installed when reqd and would throw up a message eg 50 mph at X location/station/MP this could be made to activate brakes should the speed not be reduced within a certain distance from the restriction.

On a tangent, but possible safely orientated. I notice that on the GW most if not all stations now have the fast lines barricaded off.Now i imagine that the thinking behind this is to minimise certain incidents along this line, but surely someone who is intent on such an action can still attempt it on the slow lines! I am guessing some psychologist has come up with the hypothesis that this would dissuade a such a person, but if they really wanted to complete the deed there is still the opportunity. Or is there another reason for the fencing

On a lighter note ,if there could be one, it does take away good video locations, however i am all for keeping such actions to a minimum.

 

[alxndr]

To mods, feel free to amend/delete if warranted

With the advance of digital systems, ( and i am only throwing this out as a suggestion,so willing to get actual reasons why it cannot be done rather than a NO) how easy would it be to put a screen in the cab that gives advance warnings of Temp speed restrictions. ie a sender attached to a sleeper that can easily be installed when reqd and would throw up a message eg 50 mph at X location/station/MP this could be made to activate brakes should the speed not be reduced within a certain distance from the restriction.

What you describe is not hugely dissimilar to what is where ATP (Automatic Train Protection) is installed. There if there is a TSR or ESR the usual No SR (No Speed Restriction) data plug is replaced with one with the appropriate speed data and location (although there will usually be a short period where the blue unsupervised plug is fitted which warns that there is a speed restriction but the speed is not known as it takes a while for the chips with the correct information to be blown).

Whether something similar could be implemented across the rest of the network is a harder question to answer. ATP was deemed too expensive and thus TPWS was installed, so we're not going to see that spread any further. I believe you could program a EuroBalise to do this, although at the moment they're primarily being installed for selective door opening and pantograph control as far as I'm aware. The biggest barrier to doing this would probably getting the relevant trainbourne equipment installed.

 

[SHD]

I wonder why KVB instead of CVB? **

I suppose it could possibly something to do with pronunciation of the letters, or it could be one of those little railway mysteries.*


* Such as why the industry insists that the few remaining old telegraphic codewords have to be acronyms for something (see SPATE for an example).

** [Edit: a footnote on the Wiki page explains it as "Contrôle" is abbreviated to "K", to distinguish it from "Commande"]

Sorry for not explaining the meaning of KVB before. Although I tried my best to provide details on the way it works!

Indeed I n SNCF parlance and acronyms, “contrôle” is K, and “commande” is C. The difference between the two may not be obvious: “contrôle” refers to monitoring, verifying that a system operates within a set of determined parameters, whereas “commande” refers to what is best translated in English as... control (action performed on a system by the operator to modify its state or output).

On the wiki page it states



The closest equivalent UK system is TVM, which is used by HS1 but that will all change when we move to ETCS

KVB is in use at St Pancras International. TVM is installed on high speed lines in France, Belgium and the UK and is a complete in-cab signaling system which informs the driver in real time of the current & next block permissible speed, and of course will apply emergency braking if the speed of the train is too high. TVM also automatically controls the opening/closing of the main breaker when passing neutral sections, as well as other smaller stuff.

It is said to be much more transparent for drivers than KVB.

 

[61653 HTAFC]

With regard to human error, Clarkson also said that the most dangerous part of a car is the squishy bit behind the wheel.

 

[DelW]

On a tangent, but possible safely orientated. I notice that on the GW most if not all stations now have the fast lines barricaded off.Now i imagine that the thinking behind this is to minimise certain incidents along this line, but surely someone who is intent on such an action can still attempt it on the slow lines! I am guessing some psychologist has come up with the hypothesis that this would dissuade a such a person, but if they really wanted to complete the deed there is still the opportunity. Or is there another reason for the fencing

This isn't meant to sound callous, and apologies if it comes across that way, but it's possible that risk assessment and mitigation studies have worked out that an incident on the fast lines is more disruptive, and particularly is disruptive over a wider area, than a similar incident on the slow / local lines. Plus at a station where fast trains don't stop, the fast line platforms are likely to have few or no other passengers on them; having other people around is more likely to discourage said incidents from happening at all.

 

[quantinghome]

I'm afraid I believe the opposite is true in the case of motorists. Not necessarily airbags, but front-wheel drive, better braking and all sorts of other things mean that lots of people drive as though they were invincible, when if they drove a Morris Minor or more powerful rear-wheel drive car in the same way they wouldn't last a week.

It may be true that some motorists drive more dangerously than they would otherwise because they have better brakes and so on. But the statistic speak for themselves. Road fatalities were over 6000 in the 1970s. They're now below 2000. If they has been any general worsening of driver behaviour, it's been more than offset by improvements in car safety.

 

[Bletchleyite]

This isn't meant to sound callous, and apologies if it comes across that way, but it's possible that risk assessment and mitigation studies have worked out that an incident on the fast lines is more disruptive, and particularly is disruptive over a wider area, than a similar incident on the slow / local lines. Plus at a station where fast trains don't stop, the fast line platforms are likely to have few or no other passengers on them; having other people around is more likely to discourage said incidents from happening at all.

It's a fair whack of the latter. If the fast lines are not fenced, you can't know that someone who is standing by them is a risk until they actually step off, at which point you've got one dead, one traumatised (the driver) and about three to four hours of delay to the train plus every other train that would pass there.

If they are fenced, as soon as someone steps the wrong side of the fence you know they are in the wrong, and it is possible to then challenge them before they do something stupid.

It's also worth noting that they are not there for safety reasons, though that is a useful side-effect - they are there to reduce the massive cost of disruption caused by suicides, and they have proven very successful at this.

Other than Platform Edge Doors you can't barricade the slow lines (because people sort-of need to be able to board trains) so that risk cannot be mitigated, so it isn't.

 

[philthetube]

No I don't think so. People do not drive on the road more recklessly because know that their car has an airbag to save them in the event of a crash so I doubt anyone would drive a train dangerously and expect safely equipment to save them. It's not safe to be too reliant on anything

I'm afraid I believe the opposite is true in the case of motorists. Not necessarily airbags, but front-wheel drive, better braking and all sorts of other things mean that lots of people drive as though they were invincible, when if they drove a Morris Minor or more powerful rear-wheel drive car in the same way they wouldn't last a week.
Train driving, however, is treated as a responsible professional job (with lots of different sorts of oversight and reporting) and is therefore not treated as a lark, unlike boy racers on the roads. The recruitment is rather more stringent than passing a driving test too. I very much doubt that I could get through it (or could have, even as a 20-year old. I suspect it was a rather different process then though...)

I wonder how people would drive if cars were made of cardboard, therefore giving no perception of protection.

 

[Bletchleyite]

I wonder how people would drive if cars were made of cardboard, therefore giving no perception of protection.

I suppose you would establish that by looking at what novice motorcyclists do.

 

[ejstubbs]

Jeremy Clarkson said driving standards would improve if a large spike was welded to the centre of all steering wheels!

Many people have said it, but the person who first made the suggestion was Gordon Tullock:

The name "Tullock's spike" refers to a thought experiment in which Tullock suggested that if governments were serious about making motorists drive more safely, they should mandate that a sharp spike be installed in the center of each car's steering wheel, to increase the probability that an accident would be fatal to the driver. Tullock's idea was that the normal process of risk compensation would then lead to safer driving by the affected drivers.

See also There's Actually A Name For A Steering Wheel With A Big Spike In The Middle:

Tullock came up with the idea around the time seatbelts in cars were being mandated.

 

[MarkyT]

From the Wikipedia page: https://en.wikipedia.org/wiki/Contrôle_de_vitesse_par_balises

KVB or Contrôle de Vitesse par Balises (it could be translated by Speed control by beacons) is a train protection system used in France and in London St. Pancras International station. It checks and controls the speed of moving trains.

Also now at Ashford International in UK to allow cl.374s to call.

 

[SHD]

From the Wikipedia page: https://en.wikipedia.org/wiki/Contrôle_de_vitesse_par_balises

Also now at Ashford International in UK to allow cl.374s to call.

There is a mistake in the Wikipedia article - the 1985 Flaujac rail disaster, while tragic and deadly, was not really a factor in the decision to go-ahead with KVB deployment. Flaujac was a head-on collision on a single track, on a rural line not equipped with ground-mobile communications.

The 1985 crash that proved that speed control at signal and protected points was absolutely necessary is Argenton-sur-Creuse - non-observance by the driver of a temporary speed restriction protecting a workzone, although the driver had canceled the crocodile - AWS equivalent - warning. The train derailed, and another train was coming in the opposite direction. The signalling setup was extremely complicated to decipher, which certainly contributed to the disaster. The chairman of SNCF was forced to resign, as the crash - which occurred at the end of the summer vacation - was the third deadly accident of the summer; in total, the série noire of 1985 claimed 88 lives.

 

[al78]

It may be true that some motorists drive more dangerously than they would otherwise because they have better brakes and so on. But the statistic speak for themselves. Road fatalities were over 6000 in the 1970s. They're now below 2000. If they has been any general worsening of driver behaviour, it's been more than offset by improvements in car safety.

Risk compensation is a real effect, and applies where there is a real perception of increased safety, but it is unlikely that risk compensation will totally override a safety benefit all the time.

With motorists, it is not just the safety of the driver and passengers that matters, it is the safety of non-occupants, in particular vulnerable road users. The risk associated with motoring are largely externalised on pedestrians and cyclists, and if a greater feeling of safety results in drivers compensating by taking more risks, that will manifest itself in an increase in risk for vulnerable road users, which won't be visible looking at all road KSI numbers.

 

[Ken H]

It's a bad habit when your in professional mode. I think a lot of it is caused by treating what is technically an acronym as a single word. I never think of the DRA as Drivers Reminder Appliance and simply think of is a a noun :/

TPWS - Train Protection Warning System (grids in the track)
AWS - Advanced Warning System (magnets in the track)

KVB I know what it is but sod knows what it stands for, I don't use it.

RAIB - Rail Accident Investigation Branch
SPAD - Signal Passed at Danger

PSR - Permanent Speed Restriction

BBC - British Broadcasting Corporation
HGV - Heavy Goods Vehicle

TLA - Three letter acronym

 

[Ken H]

To mods, feel free to amend/delete if warranted

With the advance of digital systems, ( and i am only throwing this out as a suggestion,so willing to get actual reasons why it cannot be done rather than a NO) how easy would it be to put a screen in the cab that gives advance warnings of Temp speed restrictions. ie a sender attached to a sleeper that can easily be installed when reqd and would throw up a message eg 50 mph at X location/station/MP this could be made to activate brakes should the speed not be reduced within a certain distance from the restriction.

On a tangent, but possible safely orientated. I notice that on the GW most if not all stations now have the fast lines barricaded off.Now i imagine that the thinking behind this is to minimise certain incidents along this line, but surely someone who is intent on such an action can still attempt it on the slow lines! I am guessing some psychologist has come up with the hypothesis that this would dissuade a such a person, but if they really wanted to complete the deed there is still the opportunity. Or is there another reason for the fencing

On a lighter note ,if there could be one, it does take away good video locations, however i am all for keeping such actions to a minimum.

Why not base it on GPS? with a decent rooftop antenna its pretty accurate. An onboard computer could then hold positions of speed restrictions, distances to stations etc. And display relevant data to the driver.
The only downside is on 4 track sections where the fast and slow lines have different speed limits. is GPS good enough to know which line you are on?

 

[Mathew S]

Why not base it on GPS? with a decent rooftop antenna its pretty accurate. An onboard computer could then hold positions of speed restrictions, distances to stations etc. And display relevant data to the driver.
The only downside is on 4 track sections where the fast and slow lines have different speed limits. is GPS good enough to know which line you are on?

What would you do when GPS goes down though? Or during periods of 'degraded accuracy'? GPS can be manipulated, interfered with, and increasingly isn't regarded as a secure enough system to use as the sole component of life & death applications.

 

[SHD]

Why not base it on GPS? with a decent rooftop antenna its pretty accurate. An onboard computer could then hold positions of speed restrictions, distances to stations etc. And display relevant data to the driver.
The only downside is on 4 track sections where the fast and slow lines have different speed limits. is GPS good enough to know which line you are on?

Something like that?
https://www.igen.fr/ipad/2016/07/la-sncf-equipe-tous-ses-conducteurs-dun-ipad-96419

Sorry, I could not find a link in English. But in a nutshell, SNCF has developed an iPad app that is now deployed for all drivers in France. It is _not_ a safety feature but a helping reminder for drivers. It replaces the traditional, paper-based “fiche train” (the detailed timetable with information on the stopping pattern, line speeds, and any recent changes such as works on the line). The monitoring of the progression of the train along the line is based on the iPad’s GPS.



On the left part of the screen: the “fiche train” data. From left to right: line speeds, kilometre posts, stations/junctions/remarkable points on the line, and timetable

 

[DerekC]

The idea that you can have "too much safety" and it's best to leave responsibility on the driver (or the signaller) has been around since the dawn of railways and was usually an excuse used by companies who didn't want to spend money on safety systems, preferring their staff to be prosecuted for manslaughter after an accident (as many were in the early days). Of course the world is different now. Decades of effort by HMRI after many, many accidents resulted in the addition of systems to prevent or trap human error. Now we rightly consider the human factors aspects of system design alongside the technology to try to do even better - so for example a system like AWS which has flaws (repetitive cancel leading to a SPAD) should not be allowed to stand alone - so we added TPWS as well, to trap the SPADs at high risk locations. Does this encourage careless driving? All the statistical evidence suggests the opposite.

The other aspect that needs to be thought about carefully is what happens when the safety systems go wrong. Railways are not very good at that bit - the old "fail to red" concept is OK as a first line of defence to prevent collisions, but many accidents in the past have happened when the railway is in a degraded state, because there is no backup system to trap errors which occur when the main system has failed. Currently we accept that the railway virtually stops when there is a serious signalling failure because the risk of moving trains is too high. That's not going to be tolerable much longer - public expectation will be that the railway gets up to date with technology that can keep trains moving.

 

[ComUtoR]

Currently we accept that the railway virtually stops when there is a serious signalling failure because the risk of moving trains is too high. That's not going to be tolerable much longer - public expectation will be that the railway gets up to date with technology that can keep trains moving.

PoSA (Proceed on Sight Authority) and ESW (Emergency Special Working) have been introduced recently to address exactly that.

 

[Ken H]

The idea that you can have "too much safety" and it's best to leave responsibility on the driver (or the signaller) has been around since the dawn of railways and was usually an excuse used by companies who didn't want to spend money on safety systems, preferring their staff to be prosecuted for manslaughter after an accident (as many were in the early days). Of course the world is different now. Decades of effort by HMRI after many, many accidents resulted in the addition of systems to prevent or trap human error. Now we rightly consider the human factors aspects of system design alongside the technology to try to do even better - so for example a system like AWS which has flaws (repetitive cancel leading to a SPAD) should not be allowed to stand alone - so we added TPWS as well, to trap the SPADs at high risk locations. Does this encourage careless driving? All the statistical evidence suggests the opposite.

The other aspect that needs to be thought about carefully is what happens when the safety systems go wrong. Railways are not very good at that bit - the old "fail to red" concept is OK as a first line of defence to prevent collisions, but many accidents in the past have happened when the railway is in a degraded state, because there is no backup system to trap errors which occur when the main system has failed. Currently we accept that the railway virtually stops when there is a serious signalling failure because the risk of moving trains is too high. That's not going to be tolerable much longer - public expectation will be that the railway gets up to date with technology that can keep trains moving.

stop and proceed was discussed on another thread. Thats when a train stops at a signal and the signal post phone doesnt work. So the rule was (may still be) that the train can proceed to the next signal at a speed that they can stop short of any obstruction. Also on the London underground (after resetting the tripcock)
But that is when all the checks and balances go. All the tech is now useless and the safety is 100 reliant on the driver seeing things. And the driver of the train behind not driving a little faster, and driving into the back of the first train.
We have also discussed permissive working on here. Again this relies on the driver seeing a train already in section.


But I wasnt just thinking of AWS when i started the thread. There are lots of things we expect to work safely. Are we so used to the tech working faultlessly that when it does fail, we are not equipped to cope?

 

[Bald Rick]

Something like that?
https://www.igen.fr/ipad/2016/07/la-sncf-equipe-tous-ses-conducteurs-dun-ipad-96419

Sorry, I could not find a link in English. But in a nutshell, SNCF has developed an iPad app that is now deployed for all drivers in France. It is _not_ a safety feature but a helping reminder for drivers. It replaces the traditional, paper-based “fiche train” (the detailed timetable with information on the stopping pattern, line speeds, and any recent changes such as works on the line). The monitoring of the progression of the train along the line is based on the iPad’s GPS.

View attachment 59482

On the left part of the screen: the “fiche train” data. From left to right: line speeds, kilometre posts, stations/junctions/remarkable points on the line, and timetable

Already in use over here with some operators, albeit in a different way.

 

[edwin_m]

Risk compensation is a real effect, and applies where there is a real perception of increased safety, but it is unlikely that risk compensation will totally override a safety benefit all the time.

With motorists, it is not just the safety of the driver and passengers that matters, it is the safety of non-occupants, in particular vulnerable road users. The risk associated with motoring are largely externalised on pedestrians and cyclists, and if a greater feeling of safety results in drivers compensating by taking more risks, that will manifest itself in an increase in risk for vulnerable road users, which won't be visible looking at all road KSI numbers.

I thought that too but just checked the statistics and pedestrian fatalities have also gone down by about 75% since 1979.
https://www.gov.uk/government/statistical-data-sets/ras30-reported-casualties-in-road-accidents (linked Excel table "casualties by type of casualty", not quotable)

 

[randyrippley]

There's an old basic adage that needs restating here as no-one else seems to have remembered it:
The more safety devices you add to a system, the less reliable that system becomes due to the need to "fail safe".
The corollary is that the more frequently you get incorrect safety warnings or checks, the less safe the system becomes due to complacency.

 

[DanDaDriver]

There's an old basic adage that needs restating here as no-one else seems to have remembered it:
The more safety devices you add to a system, the less reliable that system becomes due to the need to "fail safe".
The corollary is that the more frequently you get incorrect safety warnings or checks, the less safe the system becomes due to complacency.

They had a similar argument against putting safety guards around spinning machines in Victorian mills.