Should the third rail ban be lifted?

[Bald Rick]

Tangential question - is it likely to be acceptable, or indeed possible, to have a short section of third rail at terminal stations (e..g Uckfield) for charging BEMUs?
I would presume yes as clearly a similar arrangement (with the charging rail only energised when the train is platformed) is allowed at West Ealing, only with the charging rail in the centre of the running rails rathen than to one side.

Likely yes, with appropriate risk controls; one example might be that it is only live when a train is on the section concerned, thereby greatly reducing the risk of a passenger coming into contact with the live rail if they descend from the platform.

 

[renegademaster]

The thing with Uckfield is that's it's probably dependent on the eventual electrostar replacement. The sensible thing to do would be pick an EMU that has a battery option as an extra to the order. The catch being they still probably around for the next 15 years at least. Batteries will probably be a lot better by then.

 

[zwk500]

That assessment would need to be done for each individual station and the results could vary. Uckfield feels the most likely for third rail to pass out of the few relevant non-electrified terminals. Somewhere like Salisbury or Exeter there will be a greater risk of people going onto the tracks and variety of rolling stock/train movements complicating switching.

Uckfield being single-platform helps reduce the risk of anybody wanting to be on the other side of the track, and it should be reasonable possible to appropriately fence off the buffer stops from the high street. However it does have a significant environmental disadvantage in being located very close to the banks of the river Uck, which floods on a fairly regular basis (the river channel is not that big and the town is built in a steep valley at the start of the Weald).

Pic showing the 2000 floods (very bad), with railway top right: https://www.alamy.com/stock-photo-f...b464a51eb343fa6d9f63936c50a9c28b&searchtype=0

There are, of course, plenty of other places with flood risk that are third rail electrified, so it's certainly not a deal-breaker, but it is another thing to consider.

 

[bramling]

There are 4,456 single track kilometres of electrification with conductor rail on Network Rail infrastructure, which includes various sidings and loops.

To electrify the infill areas commonly proposed on these pages - North Downs, Uckfield, and Ore to Ashford - would be a further c215km. Thats as near as makes no difference an extra 5%. On a route mileage basis it will be higher (I guess 7%) but I don’t have those numbers to hand, so will stick with 5%.

Extrapolating the numbers provided by @ainsworth74 above, that implies an additional 6-7 fatalities, and 20-21 injuries over the next three decades were those routes to be electrified with conductor rail. That’s just about 1 incident per year on these new sections. I note the suggestion that rural routes are less likely to see incidents, I suspect the numbers don’t bear that out, but I don’t know. However it is likely that the addition of third rail in areas where there currently is none will potentially lead to a higher rate of incidents than the average, at least for an initial period. I don’t have evidence of that so will exclude it. And, also, I suspect that incidents are correlated more to route mileage than track mileage, but again will exclude that and stick with the lower, 5% number, on track mileage whcih leads to the extrapolation above. (For example, one could use different yet reasonable assumptions that would broadly double the anticipated extra incident numbers).

Now, it might be that the benefits to society of electric trains on these lines is worth the fact that there would be, on average, an incident every year on them, but you will need to demonstrate that through risk assessment compared to alternatives, one of which is ‘do nothing.’ If, say, you are the MD of the Southern Region, and that assessment is not done, and you electrify with conductor rail anyway*, you will find yourself in the dock in court in short order following the first incident.

In the current world where battery trains are in service in the UK and worldwide and therefore clearly a possible alternative, you would need to demonstrate that the cost of buying and maintaining battery trains for these lines is grossly disproportionate compared to the cost of buying and maintaining straight EMUs plus 215km of third rail electrification (including all the necessary distribution equipment, power supplies, changes to signalling, changes to track, level crossings, signage, etc), plus not having the other benefits (safety, performance, and financial) that battery trains have. Grossly disproportionate has a defintion in these circumstances, which I shan’t go into detail of here, as it gets complex. The short version is that the value of each life saved / injury avoided is multiplied by at least 2.5 times the norm used in socio-economic business cases.

Therefore, imagine again you are the MD of Southern Region. You have done the relevant risk assessments, and all the paperwork, and found that the whole life cost of battery trains is lower than or the same as electrifying with conductor rail. Nevertheless you sign the paperwork to deliver third rail*. Someone, at some point, has a fatal incident. You will be charged with Manslaughter by gross negligence, be found guilty, and sent to prison.

Therefore the only circumstance where it makes sense to electrify these sections with third rail is if it can be demonstrated, unequivocally, that the cost of the alternative(s) on a whole life basis is grossly disproportionate compared to the cost of third rail electrification, taking into account the expected lives lost and injuries occurring.


It is my contention, based on my knowledge and experience of how much these things cost, that battery trains in this example would be much, much cheaper, as well as safer, than new third rail.

Perhaps this thread could be bookmarked somehow, as this keeps cropping up.

* It is hypothetical of course, but if the MD of Southern Region did sign off on a new conductor rail installation with no risk assessment, or an assessment which showed that alternatives were better, then the ORR would not approve the entry into service of the equipment when it was built, and the MD would be sacked (if they hadn’t been sacked already).

It’s interesting to observe that all of the above largely boils down to *could* the DC network be expanded, to which this does provide a pretty watertight “no not really” answer.

However the premise of the thread is *should* the network be extended. The legislative issues could presumably be sidestepped if politicians were prepared to change the law, albeit I’m not sure if there would be the appetite for it considering the availability of batteries.

It’s probably unfortunate that BR didn’t include Ashford-Hastings and Uckfield as part of the adjacent Hastings and East Grinstead schemes. Was this ever seriously looked at, or were these lines just too much of a backwater at the time? One would think that Ashford-Hastings could have been minimally specified for a maximum half-hourly 4-car service, with some ability to utilise existing supplies at either end.

 

[778]

It’s interesting to observe that all of the above largely boils down to *could* the DC network be expanded, to which this does provide a pretty watertight “no not really” answer.

However the premise of the thread is *should* the network be extended. The legislative issues could presumably be sidestepped if politicians were prepared to change the law, albeit I’m not sure if there would be the appetite for it considering the availability of batteries.

It’s probably unfortunate that BR didn’t include Ashford-Hastings and Uckfield as part of the adjacent Hastings and East Grinstead schemes. Was this ever seriously looked at, or were these lines just too much of a backwater at the time? One would think that Ashford-Hastings could have been minimally specified for a maximum half-hourly 4-car service, with some ability to utilise existing supplies at either end.

According to another thread on this forum, BR was planning to electrify the Marshlink and Uckfield lines in 1995, but the plans were dropped when the railway was privatised.

 

[MarkyT]

The thing with Uckfield is that's it's probably dependent on the eventual electrostar replacement. The sensible thing to do would be pick an EMU that has a battery option as an extra to the order.

Manufacturers seem to be offering these options. Alstom, with the recent Irish order for example, the latest Siemens concepts, and of course the OG modern British train, Stadler's groundbreaking FLIRT.

The catch being they still probably around for the next 15 years at least. Batteries will probably be a lot better by then.

The SE metro fleet replacement may specify all trains with a moderate battery capability for emergencies, depot movements etc, and its likely the size of such a battery could be varied fairly easily in a modern design. A shorter-term option for Uckfield might be an add-on order to the SE contract for a similar train, configured for longer-distance regional rather than high-density urban service, and with a larger battery for Uckfield, of course. Such vehicles might be maintained at the same London area depot as their SE cousins.

 

[yorksrob]

It’s negligible, and certainly not “a lot”. A few tonnes of battery on, say 150 tonnes of train (for a 4 car). Besides, the energy required to move the extra weight is mostly recoverable during braking - it goes back into the battery.



We do that very well now! Its no different to the current position.




Well the answer there is to buy more battery trains. Again no different to the current position.

I think that we're very lucky that BR took the initiative that it did in the 1980's/early 90's to undertake those infills/extensions, otherwise the network in the South would be very patchy and awkward to operate indeed.

== Doublepost prevention - post automatically merged: 13 Mar 2026 ==

Nothing to say that the yellow shrouding boards found in depots couldn't be put in either side of the third rail for a few metres beyond the level crossings (already past the gaps of the third rail in existence around crossings).

Indeed. A lot of crossings have wooden "cattle grids" to make trespass difficult anyway. Third rail in stations has had shrouding boards at least since I were a lad.

 

[MarkyT]

I think that we're very lucky that BR took the initiative that it did in the 1980's/early 90's to undertake those infills/extensions, otherwise the network in the South would be very patchy and awkward to operate indeed.

Some of those extensions were carried out very economically, with compromises in HV feeder voltage and the number of substations. That led to load limitations that still hamper capacity and performance today. If EMUs all had batteries, such sections might become more manageable without further infrastructure interventions, with each train able to blend in battery power to maintain performance during any short periods when supply voltage drops significantly due to peaks of demand.

 

[yorksrob]

Some of those extensions were carried out very economically, with compromises in HV feeder voltage and the number of substations. That led to load limitations that still hamper capacity and performance today. If EMUs all had batteries, such sections might become more manageable without further infrastructure interventions, with each train able to blend in battery power to maintain performance during any short periods when supply voltage drops significantly due to peaks of demand.

It's true, although I believe they managed to get a 4CEP down to Weymouth once.

 

[35B]

It's true, although I believe they managed to get a 4CEP down to Weymouth once.

Indeed, the SEG took a 4-CEP + 4-EBP formation down there (https://www.sixbellsjunction.co.uk/90s/910112se.htm)

 

[renegademaster]

A shorter-term option for Uckfield might be an add-on order to the SE contract for a similar train, configured for longer-distance regional rather than high-density urban service, and with a larger battery for Uckfield, of course.

It's not going to be ideal for Selhurst to replace a somewhat similar micro fleet with a completely different one. Especially considering the 1 Turbostar an hour into London is pretty much a drop in the ocean of London emmisions so their's no real pressure to be rid of them

 

[yorksrob]

Indeed, the SEG took a 4-CEP + 4-EBP formation down there (https://www.sixbellsjunction.co.uk/90s/910112se.htm)

Oh, that sounds magnificent (although I imagine I'd have difficulty going long distance on the EPB non-stop nowadays ).

 

[Dr Hoo]

According to another thread on this forum, BR was planning to electrify the Marshlink and Uckfield lines in 1995, but the plans were dropped when the railway was privatised.

Can you provide a link, please?

Although I was in Scotland around that time I find the claim quite extraordinary. For a start even though the train operations were still part of BR at that time the infrastructure had passed to Railtrack in April 1994. The sheer change in safety culture that had been ushered in by the Hidden Report into the Clapham Junction crash (published in September 1989 after the Electricity at Work Regulations had gone though Parliament back in April) had led to an overdue transformation in 'compliance' and oversight. Investment capital was still extremely scarce after the 1991 financial crisis and for the next few years was focussed on completing Channel Tunnel related works. Ironically this had included belated delivery of third rail schemes such as the West London Line and Tonbridge-Redhill that had essentially been committed ever since the Treaty of Canterbury in 1986. The management culture of what had been Network SouthEast had also changed after various senior management moves.

 

[yorksrob]

Hooray for the international treaty ! We should have snuck the Marshlink in at the time.

 

[Tio Terry]

Is there a third rail ban?

I thought that the legal position in regard to protection from bare live conductors had changed in such a way that any new installations were effectively banned without an adequate safety risk assessment that showed that the risk was acceptable.

That would not be retrospective but would apply to any proposed new installations.

 

[yorksrob]

Is there a third rail ban?

I thought that the legal position in regard to protection from bare live conductors had changed in such a way that any new installations were effectively banned without an adequate safety risk assessment that showed that the risk was acceptable.

That would not be retrospective but would apply to any proposed new installations.

Yes, that's a de facto third rail ban.

 

[Tio Terry]

Yes, that's a de facto third rail ban.

No.

That is a very sensible safety requirement.

 

[yorksrob]

No.

That is a very sensible safety requirement.

No, it is a ban - to all intents and purposes though.

 

[Tio Terry]

No, it is a ban - to all intents and purposes though.

No, not at all.

There is a need to meet safety requirements.

Are you saying safety requirements should be ignored?

 

[Bald Rick]

Can you provide a link, please?

Although I was in Scotland around that time I find the claim quite extraordinary. For a start even though the train operations were still part of BR at that time the infrastructure had passed to Railtrack in April 1994. The sheer change in safety culture that had been ushered in by the Hidden Report into the Clapham Junction crash (published in September 1989 after the Electricity at Work Regulations had gone though Parliament back in April) had led to an overdue transformation in 'compliance' and oversight. Investment capital was still extremely scarce after the 1991 financial crisis and for the next few years was focussed on completing Channel Tunnel related works. Ironically this had included belated delivery of third rail schemes such as the West London Line and Tonbridge-Redhill that had essentially been committed ever since the Treaty of Canterbury in 1986. The management culture of what had been Network SouthEast had also changed after various senior management moves.

I don’t have a link, but I’m reasonably sure* that NSE had a stated objective of electrifying the rest of the North Downs, Uckfield and Ore - Ashford in around 1992/3. But then the recesson intervened and all non Channel Tunnel investment stopped; then privatisation followed and by then it was too late.

*I’m sure I’ve read it somewhere. Also an ‘informed‘source’** told me when we were talking about the subject a year or two ago.


**Chris Green

 

[bramling]

Indeed, the SEG took a 4-CEP + 4-EBP formation down there (https://www.sixbellsjunction.co.uk/90s/910112se.htm)

One of the slamdoor farewell tours ran a CEP+VEP+CIG combination down there. I was half expecting it to be somewhat sluggish on the climb going out of Weymouth, but it was surprisingly sprightly.

Of course, as ever the issue with some of the schemes is not what can be run as a “one off”, but what can be run day in day out, and in particular if an item of plant needs to be out of commission for whatever reason.

 

[amahy]

There is a need to meet safety requirements.

Are you saying safety requirements should be ignored?

But said "safety requirements" are all over the place, like how 132 deaths caused by the 3rd rail in 30 years (see post #132) is deemed unsafe, but 1,500+ on the roads in a year is fine, according to the ORR and DfT. (Note that this assumption is made on the grounds that these organisations do basically nothing to address the latter problem.)

 

[778]

I don’t have a link, but I’m reasonably sure* that NSE had a stated objective of electrifying the rest of the North Downs, Uckfield and Ore - Ashford in around 1992/3. But then the recesson intervened and all non Channel Tunnel investment stopped; then privatisation followed and by then it was too late.

*I’m sure I’ve read it somewhere. Also an ‘informed‘source’** told me when we were talking about the subject a year or two ago.


**Chris Green

I think Bletchley - Bedford was supposed to be electrified as well?

 

[Tio Terry]

But said "safety requirements" are all over the place, like how 132 deaths caused by the 3rd rail in 30 years (see post #132) is deemed unsafe, but 1,500+ on the roads in a year is fine, according to the ORR and DfT. (Note that this assumption is made on the grounds that these organisations do basically nothing to address the latter problem.)

I think you are missing the regulations applicable to bare electrical conductors.

What was acceptable in the past is no longer acceptable in the present.

 

[WAO]

I think you are missing the regulations applicable to bare electrical conductors.

What was acceptable in the past is no longer acceptable in the present.

I think that "regulations" are the problem; they are not the Laws of the Medes and the Persians, and ought to be subject to question and revision. That is a role of the Chartered Engineer (as opposed to the lower grades). The "regulations" for 25kV have been questioned publicly at senior level recently. As has been pointed out dc casualties include suicides (and no doubt intentional adult trespass) so true accidents are much rarer, which is why the existing (but suboptimal) dc system is perpetuated and modest percentage infills are unobjectionable. The battery argument should then be settled on its economic and operational merits.

The predominant hazard on the railway is kinetic not electrical energy.

WAO

 

[Magdalia]

But said "safety requirements" are all over the place, like how 132 deaths caused by the 3rd rail in 30 years (see post #132) is deemed unsafe, but 1,500+ on the roads in a year is fine, according to the ORR and DfT. (Note that this assumption is made on the grounds that these organisations do basically nothing to address the latter problem.)

The 132 deaths caused by 3rd rail in 30 years are not comparable with all road deaths, a more sensible comparison is with pedestrian deaths.

There are 4,456 single track kilometres of electrification with conductor rail on Network Rail infrastructure, which includes various sidings and loops.

132 deaths in 30 years is about 4.5 deaths per year, that's roughly 1 death per 1,000 track km per year.

Total pedestrian road deaths are about 400 per year, and total road length is about 400,000km. That's about 1 pedestrian death per 1,000 road km per year.

For people on foot a 3rd rail electrified railway is similarly dangerous to a road.

And of course it is nonsense to suggest that nothing is done to address safety issues on the roads. Here is just one recent example of a road project done to improve safety:

Second phase of Cambridge Addenbrooke's roundabout work to start

The outer ring of the roundabout will be closed overnight for 15 weeks this summer.

www.bbc.co.uk

A second phase of works will start this month to try to make a roundabout safer.

Construction is being carried out on the Addenbrooke's Hospital roundabout in Cambridge to improve safety for pedestrians, cyclists and motorists.

 

[Bald Rick]

As has been pointed out dc casualties include suicides

For the second time, the DC casualties do not include suicides.

 

[WAO]

Apologies, per your post#171. Mea Culpa.

Suicides across then system at about 250/year are an awful problem, for the staff also.

WAO

 

[Technologist]

Doesn't make much sense as described. What would your shoebox device actually do? How would it be actuated when a train passed over it? How would the current get to it? (That would need extra draggy wires, presumably). If you run the system at a higher voltage you still need "wires". Oh, and of course higher voltage would need new trains and new substations -or at least very expensive conversion of old ones. It sounds more like about £10M/km to me. And if you are going to use a BEMU in case the switches fail, why bother with the third rail at all?

The BEMU still needs partial electrification to function, in many cases we might also want to use 3rd rail to provide the "charge island" to allow them to run much further off the network.

My proposed solution would have an insulated bus bar to carry the 3rd rail current, this would have a cost commensurate with a rail. Every 100m or so this would be connected to a 100m long section of the 3rd rail via the breaker box. If a train is not present then the box does not connect the 3rd rail section to the energised bus bar, were someone/thing to bridge between the 3rd rail and a running rail no current would flow. When the box detects a train it connects the bus bar to the 3rd rail, potentially checking for a short circuit before doing so. The train passes over the energised section completing the circuit, when it leaves the circuit the box disconnects that section of 3rd rail.

Thus the only live sections of 3rd rail are under a train or recently under a train. We can therefore make an argument that we could run the 3rd rail at a much higher voltage potentially allowing much higher power transfer and much less frequent sub stations. This might potentially be a more resilient and lower cost solution than 25kv OHLE.

Since this would be used on new sections of line initially we would have 3rd rail BEMUs that were also able to operate on 750VDC 3rd rail, with modern power electronics multiple voltages are not a massive challenge.

 

[yorksrob]

No, not at all.

There is a need to meet safety requirements.

Are you saying safety requirements should be ignored?

Absolutely not. The safety requirements pertaining to the third rail network as a whole should be followed.

And it is a de facto ban.