RMweb Premium phil-b259 Posted July 19, 2019 Author RMweb Premium Share Posted July 19, 2019 7 minutes ago, martin_wynne said: Hopefully not copied and pasted? Otherwise whoever wrote "uninterpreted" several times instead of "uninterrupted" is in the wrong job. Martin. Spelling was never my strong point - and autocorrect doesn't always help... 2 2 Link to post Share on other sites More sharing options...
jim.snowdon Posted July 19, 2019 Share Posted July 19, 2019 15 minutes ago, martin_wynne said: Hopefully not copied and pasted? Otherwise whoever wrote "uninterpreted" several times instead of "uninterrupted" is in the wrong job. Martin. Having a pretty good idea what Phil's day job is, I wouldn't doubt the veracity of his comments. Jim 2 1 Link to post Share on other sites More sharing options...
RMweb Gold martin_wynne Posted July 19, 2019 RMweb Gold Share Posted July 19, 2019 9 minutes ago, phil-b259 said: Spelling was never my strong point - and autocorrect doesn't always help... Had you written "interpreted" it would have made a telling change of wording. Simply having an uninterrupted view of something doesn't necessarily mean that you can interpret what you are seeing. cheers, Martin. Link to post Share on other sites More sharing options...
43110andyb Posted July 19, 2019 Share Posted July 19, 2019 Latest update- Published 4 July 2019 Last updated 19 July 2019 — see all updates From: Rail Accident Investigation Branch At around 09:52 hrs on Wednesday 3 July 2019, two track workers were struck and fatally injured by a passenger train at Margam East Junction on the South Wales Main Line. A third track worker came very close to being struck. These three workers were part of a group of six staff, who were undertaking scheduled track maintenance on lines that were still open to traffic. The train, which was travelling from Swansea to London Paddington, was approaching Margam on the up line at around 73 mph (117 km/h). Its driver saw three track workers walking away from him on the adjacent line and, beyond them, three more track workers on the line ahead of his train. He sounded the train horn and applied the emergency brakes. The track workers walking on the adjacent line became aware of the train approaching and tried to warn their colleagues as the train passed them. The three track workers on the up line were working on a set of points, using a petrol-engined tool for loosening and tightening large nuts. Consequently, at least one of the workers was wearing ear defenders. CCTV images taken from a camera at the front of the train suggest that the workers did not become aware of the train until it was very close to them. By this time, it was travelling at around 50 mph (80 km/h). The RAIB’s investigation will identify the sequence of events that led to the accident and consider: what might have influenced the actions of those on site the protection arrangements that were in place the planning of the work and the implementation of Network Rail’s standard for keeping people safe on or near the line any relevant underlying management or organisational factors Our investigation is independent of any investigation by the railway industry, the British Transport Police or by the industry’s regulator, the Office of Rail and Road. We will publish our findings, including any recommendations to improve safety, at the conclusion of our investigation. This report will be available on our website. You can subscribe to automated emails notifying you when we publish our reports. 2 Link to post Share on other sites More sharing options...
Ken.W Posted July 19, 2019 Share Posted July 19, 2019 (edited) A very tragic event indeed, even more so if what's been hinted above is correct, though we'll of course have to wait of the final report to see. One thing I will now comment upon from the details now given, which was much discussed and speculated previously. There was some speculation as to why the train and passengers were detained what to some seemed an exceptional amount of time. The train is reported as traveling "at around 50 mph", with the emergency brakes having already been applied at the time of the incident. I would expect then, this being an 800, that it would have then come to a stand in under a train length.... This also tallys with the previous post regarding the window blinds being lowered. I have stopped at a similar speed and distance, due fortunately to nothing more than a signal reversion, and that was with an HST.... Approaching Berwick station northbound, booked non-stop but on cautionary signals so brake in step 2 and about 50 as I reach the platform ramp when the next signal ahead, just short of the platform end, reverts back to danger. Bang brake to emergency. Not only did I actually stop short of the signal, the rear coach and power car would have still been short of the platform. Edited July 19, 2019 by Ken.W 2 1 1 Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted July 20, 2019 RMweb Gold Share Posted July 20, 2019 16 hours ago, martin_wynne said: Hopefully not copied and pasted? Otherwise whoever wrote "uninterpreted" several times instead of "uninterrupted" is in the wrong job. Martin. The authoritative source, or probably the most relevant in this instance, is Handbook 20 - https://catalogues.rssb.co.uk/rgs/rulebooks/GERT8000-HB20 Iss 2.pdf 1 2 Link to post Share on other sites More sharing options...
43110andyb Posted July 20, 2019 Share Posted July 20, 2019 1 hour ago, The Stationmaster said: The authoritative source, or probably the most relevant in this instance, is Handbook 20 - https://catalogues.rssb.co.uk/rgs/rulebooks/GERT8000-HB20 Iss 2.pdf Very similar but be mindful that Safe work leader (SWL) is not currently used apart from I believe a small section of projects division. The work group would be using a COSS & PIC (person in charge), they can be one in the same person but with complex work COSS/PIC duties can be shared out within a group if required. Duties of a COSS -https://catalogues.rssb.co.uk/rgs/rulebooks/GERT8000-HB7 Iss 5.pdf 2 Link to post Share on other sites More sharing options...
RMweb Gold The Johnster Posted July 20, 2019 RMweb Gold Share Posted July 20, 2019 15 hours ago, Ken.W said: A very tragic event indeed, even more so if what's been hinted above is correct, though we'll of course have to wait of the final report to see. One thing I will now comment upon from the details now given, which was much discussed and speculated previously. There was some speculation as to why the train and passengers were detained what to some seemed an exceptional amount of time. The train is reported as traveling "at around 50 mph", with the emergency brakes having already been applied at the time of the incident. I would expect then, this being an 800, that it would have then come to a stand in under a train length.... This also tallys with the previous post regarding the window blinds being lowered. I have stopped at a similar speed and distance, due fortunately to nothing more than a signal reversion, and that was with an HST.... Approaching Berwick station northbound, booked non-stop but on cautionary signals so brake in step 2 and about 50 as I reach the platform ramp when the next signal ahead, just short of the platform end, reverts back to danger. Bang brake to emergency. Not only did I actually stop short of the signal, the rear coach and power car would have still been short of the platform. The original BBC website report showed what appeared to be a sheeted victim being stretchered away and the train standing straddling the turnout, supporting the impression of a full emergency brake application shortly before the victims were struck and from around 50mph at the location of the incident on a dry rail. This photo was taken from an overbridge about half a mile in rear and is heavily telephotoed, but it looks to me as if the turnout is under the 2nd to last vehicle and the sheeted victim a little ahead of that; of course, he'd have been carried by the impact a little way before even starting his (not very pleasant) work. As for the time the train was kept standing, it has to be examined by qualified staff before being allowed to continue it's journey, over and above the requirements of the Transport Police's investigation, which demands closure of all running lines while it is in progress. A C&W examiner presumably had to be brought in from either Malefant (Swansea) or Stoke Gifford (Bristol Parkway), and as there is no road access to that location, might have taken some time to get there given that he'd have had to walk a good distance to the site. The BBC report mentioned that passengers had praised the way they were dealt with by the staff concerned (mostly the train manager I assume) and kept informed. Power was available on the train so the airco was kept running and refreshments were available; it was an unpleasant experience for the passengers no doubt but no physical discomfort was experienced by them as a result of the stoppage; anyone who witnessed any part of the direct aftemath or the recovery operation may well have felt uncomfortable, though. The curtain drawing seems to have been done on passengers' own initiative as there was a party of 6th form schoolchildren occupying that part of the train; I do not know if they were accompanied by a teacher. As far as I am aware, nobody complained about the delay; people generally show a bit of understanding in these terrible situations, and a common humanity comes into play. Again, as far as I aware, nobody reported suffering from shock or being ill, either. The staff on the train and those trackside in the recovery operation seem to have behaved admirably in circumstances nobody ever wants to have to deal with, as did the passengers. 3 Link to post Share on other sites More sharing options...
Southernman46 Posted July 22, 2019 Share Posted July 22, 2019 On 11/07/2019 at 19:01, jim.snowdon said: Indeed not, but that sort of training material, even though the incidents are staged, probably got the point over better than today's training presentations do. Apart from the strap men who get it wrong, how many people have, for example, seen what at 750V DC short circuit looks like, or have ever seen a short circuiting bar used on the real railway? Jim Yup - short circuiting bar trials at Wimbledon Substation where we had all 4 rectifiers feeding the siding adjacent to the Sub with pretty much only the cabling to attenuate the fault. Proved that the SR s/c bar is a sound design and the LM "flop-down" version is shite (we never actually managed to recover one after it's journey into the undergrowth). Highest recorded fault current was (I kid you not) 84kA at 750v. and many other times - exploding pots / shoegear / set of clamp fishplates on one memorable occasion / DC Circuit breaker commission tests and my personal favourite (apart from the time me and the Wimbledon SM almost got blown up at Barnes - described in a post above) was the time my rail-measuring wheel slipped out of its handle grip and fell neatly across the conductor and running rail at Farnborough ……………. after contemplating this for a few seconds and "enjoying" the pyrotechnics proceeded to remove said apparatus with its odometer box now on fire with a well-aimed boot. Cue embarrassing call to Eastleigh ECR ………………….. Happy days 1 2 Link to post Share on other sites More sharing options...
jim.snowdon Posted July 22, 2019 Share Posted July 22, 2019 2 hours ago, Southernman46 said: Yup - short circuiting bar trials at Wimbledon Substation where we had all 4 rectifiers feeding the siding adjacent to the Sub with pretty much only the cabling to attenuate the fault. Proved that the SR s/c bar is a sound design and the LM "flop-down" version is shite (we never actually managed to recover one after it's journey into the undergrowth). Highest recorded fault current was (I kid you not) 84kA at 750v. Which is why I eventually managed to get it banned from the Liverpool area, at least for NR use, and the SR type bar made standard instead. The short bar is still carried on the 507/508 stock, but only because they had been modified some time in the past such that the long Southern Region bar can no longer be fitted, and use of a short circuiting bar by tran crew is a rare event these days, especially with the much improved communications. Its days are now numbered by the impending arrival of replacement stock that will carry the long bar. Jim 1 2 Link to post Share on other sites More sharing options...
Zomboid Posted July 22, 2019 Share Posted July 22, 2019 9 hours ago, Southernman46 said: Highest recorded fault current was (I kid you not) 84kA at 750v. I was told of how Wimbledon was used to test to destruction the capabilities of the Main DC breakers. I don't remember the details now but I think it took over 40kA to ruin at least one design. Chosen because it was on top of the grid, and all those rectifiers will get the fault up about as high as it's possible to anywhere on NR. How you broke 84kA without destroying the track breakers though... Tripping the rectifier HV breakers instead? Link to post Share on other sites More sharing options...
jim.snowdon Posted July 22, 2019 Share Posted July 22, 2019 1 hour ago, Zomboid said: I was told of how Wimbledon was used to test to destruction the capabilities of the Main DC breakers. I don't remember the details now but I think it took over 40kA to ruin at least one design. Chosen because it was on top of the grid, and all those rectifiers will get the fault up about as high as it's possible to anywhere on NR. How you broke 84kA without destroying the track breakers though... Tripping the rectifier HV breakers instead? I have a copy of the report from that testing, and if I recall correctly, the objectives were to prove that the methods for short circuiting (bars & straps) would withstand the fault current from a four rectifier substation, of which Wimbledon was one of very few, as well as establishing what the fault currents would be. Even now, there are no many four rectifier substations. Two and three are more common, and have commensurately lower fault currents. Jim 1 2 Link to post Share on other sites More sharing options...
Trog Posted July 22, 2019 Share Posted July 22, 2019 When the DC rail at Farringdon (City Widened Lines) was new one of our track gangs was working there, with no isolation needed due to the con rail not yet having been commissioned. The supervisor felt uneasy about working next to un-isolated con rail even though he knew that it was still un-commissioned. So just to be sure to be sure (him being of the Irish persuasion) he dropped a fish plate onto the con and running rails. BANG! The short apparently carried on going until the fishplate melted and dripped off the rails. 5 1 Link to post Share on other sites More sharing options...
RMweb Premium Chris116 Posted July 23, 2019 RMweb Premium Share Posted July 23, 2019 10 hours ago, Trog said: When the DC rail at Farringdon (City Widened Lines) was new one of our track gangs was working there, with no isolation needed due to the con rail not yet having been commissioned. The supervisor felt uneasy about working next to un-isolated con rail even though he knew that it was still un-commissioned. So just to be sure to be sure (him being of the Irish persuasion) he dropped a fish plate onto the con and running rails. BANG! The short apparently carried on going until the fishplate melted and dripped off the rails. Never ASSuME anything on the railway! Well done that supervisor. 5 Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted July 23, 2019 RMweb Premium Share Posted July 23, 2019 Throwing a fish plate across a power circuit like that if you think it might be live isn't exactly the safest of things to do either. 2 Link to post Share on other sites More sharing options...
RMweb Premium phil-b259 Posted July 23, 2019 Author RMweb Premium Share Posted July 23, 2019 1 hour ago, jjb1970 said: Throwing a fish plate across a power circuit like that if you think it might be live isn't exactly the safest of things to do either. Not least because as the supervisor found out the 'trip' current of traction circuit breakers is extremely high and will NOT necessarily trip even with a dead short between the conductor and running rails - you run the risk of molten metal flying about..... Always best to treat it as live at all times (something those of us who mainly work outside possessions do automatically....) 6 Link to post Share on other sites More sharing options...
Trog Posted July 23, 2019 Share Posted July 23, 2019 1 hour ago, jjb1970 said: Throwing a fish plate across a power circuit like that if you think it might be live isn't exactly the safest of things to do either. When doing something like that you would make sure you were not looking at it as the plate dropped. Also why would that be an unsafe thing to do on a con-rail that you have been assured by the electrical engineers is not connected to the power yet. Hence why they can not give you an isolation. Link to post Share on other sites More sharing options...
Trog Posted July 23, 2019 Share Posted July 23, 2019 37 minutes ago, phil-b259 said: Not least because as the supervisor found out the 'trip' current of traction circuit breakers is extremely high and will NOT necessarily trip even with a dead short between the conductor and running rails - you run the risk of molten metal flying about..... Always best to treat it as live at all times (something those of us who mainly work outside possessions do automatically....) What breakers? We were told at the time that 'someone' had accidentally connected the rails directly to the DC power supply. 1 2 Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted July 23, 2019 RMweb Premium Share Posted July 23, 2019 If you have any reason whatsoever to suspect something is live, or has accumulated a static charge which has not been earthed, then the safe system of work should have suitable procedures in place to request that it is proven to be isolated and dead. The forces that can be released by inducing short circuits or full earth faults can be huge even when protection acts very quickly. Link to post Share on other sites More sharing options...
RMweb Premium phil-b259 Posted July 23, 2019 Author RMweb Premium Share Posted July 23, 2019 6 minutes ago, Trog said: When doing something like that you would make sure you were not looking at it as the plate dropped. Also why would that be an unsafe thing to do on a con-rail that you have been assured by the electrical engineers is not connected to the power yet. Hence why they can not give you an isolation. Because, as happened in this case, people and procedures are not guaranteed to be perfect 100% of the time. Which neatly brings the topic back to the incident in Wales..... 2 Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted July 23, 2019 RMweb Premium Share Posted July 23, 2019 As a senior authorised person in electricity generation I could be asked to demonstrate that any apparatus was dead by touching it before people started work under a permit I was issuing, it's a pretty effective way to make sure whoever has told you something is safe has confidence in their safety precautions. 3 1 1 Link to post Share on other sites More sharing options...
RMweb Premium phil-b259 Posted July 23, 2019 Author RMweb Premium Share Posted July 23, 2019 (edited) 21 minutes ago, jjb1970 said: As a senior authorised person in electricity generation I could be asked to demonstrate that any apparatus was dead by touching it before people started work under a permit I was issuing, it's a pretty effective way to make sure whoever has told you something is safe has confidence in their safety precautions. Which is all very well for stuff that was in work and subsequently switched off for work to take place. A bit different from the incident Trog outlined where the 3rd rail was, according to all the records not yet energised / commissioned and thus should not have been switched on in the first place. This distinction between 'new works' and 'maintenance works' is why the post Clapham Junc crash S&T world is split into 2 very distinct disciplines each with their own testing regimes that reflect the different risks:- (1) 'Maintenance testers' who can only replace on a like for like basis (on the assumption that whatever is installed is correct / live / working) (2) 'New works testers' who can only install / commission new equipment Edited July 23, 2019 by phil-b259 2 Link to post Share on other sites More sharing options...
RMweb Premium St Enodoc Posted July 23, 2019 RMweb Premium Share Posted July 23, 2019 53 minutes ago, jjb1970 said: If you have any reason whatsoever to suspect something is live, or has accumulated a static charge which has not been earthed, then the safe system of work should have suitable procedures in place to request that it is proven to be isolated and dead. The forces that can be released by inducing short circuits or full earth faults can be huge even when protection acts very quickly. 51 minutes ago, phil-b259 said: Because, as happened in this case, people and procedures are not guaranteed to be perfect 100% of the time. Which neatly brings the topic back to the incident in Wales..... You must always treat any circuit as live unless you can be absoultely sure that it is not. 4 Link to post Share on other sites More sharing options...
Trog Posted July 23, 2019 Share Posted July 23, 2019 1 hour ago, jjb1970 said: As a senior authorised person in electricity generation I could be asked to demonstrate that any apparatus was dead by touching it before people started work under a permit I was issuing, it's a pretty effective way to make sure whoever has told you something is safe has confidence in their safety precautions. it would never work on the railway, as the incompetent have to be kept in a fit state to be promoted out of harms way. 3 2 Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted July 24, 2019 RMweb Premium Share Posted July 24, 2019 8 hours ago, phil-b259 said: Which is all very well for stuff that was in work and subsequently switched off for work to take place. A bit different from the incident Trog outlined where the 3rd rail was, according to all the records not yet energised / commissioned and thus should not have been switched on in the first place. This distinction between 'new works' and 'maintenance works' is why the post Clapham Junc crash S&T world is split into 2 very distinct disciplines each with their own testing regimes that reflect the different risks:- (1) 'Maintenance testers' who can only replace on a like for like basis (on the assumption that whatever is installed is correct / live / working) (2) 'New works testers' who can only install / commission new equipment That's an issue of control responsibility, but it does not alter the fundamental principles of safe working on electrical apparatus. If apparatus has not been handed over by a new construction contractor or another division of a company then it should still be under their control and clearly delineated. Electrical conductors do not have to be connected to be hazardous, they can accumulate induced voltage, be energised for testing etc. Cross boundary procedures and processes should manage the interface between the two systems. Link to post Share on other sites More sharing options...
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