Railway Safety: Analysing Risks and Causes

Transcription

1 Raiway Safety: Anaysing Risks and Causes Say Brearey Raitrack Safety and Standards Directorate 8 December 2000

2 Stop a the trains, cut off the signaing Prevent the TOCs from running with their new paything Sience the dieses, a the money is spent S&SD s found a hazardous event - with apoogies to WH Auden

3 Agenda Reguatory Framework Permissioning Regimes ROTS RSC Reg s 2000 R2P2 Safety Decision Framework VPF Outrage Catastrophic Events Risk Toos Decision Processes 2F S&SD Safety Risk Mode Ladbroke Grove Pubic Inquiry Europe

4 Overview Roe of S&SD Raiway safety cases Safety decision framework S&SD s safety risk mode Mode deveopment Risk profies Exampe of mode uses

5 Raitrack S&SD s Safety Roes Produce Raiway Group Safety Pan Estabish framework for risk contro, inc standards for system safety & safe interworking Manage Raitrack s safety case Accept train operators safety cases Audit & assess safety performance of Raiway Group members Advice and safety eadership

6 Raiway Safety Cases Raiway s safety case cascade is unique Raitrack safety case sets out: nature of operations on infrastructure risks arising safety management arrangements safety decision framework Raitrack safety case accepted by HMRI Train and station operators safety cases accepted by Raitrack Safety & Standards Directorate (S&SD)

7 RSC Reguations 2000 S&SD becomes Raiway Safety HSE to accept train and station operators safety cases aso Singe process to faciitate invovement by Raitrack, Raiway Safety and HSE Safety case cascade broken? Interfaces?

8 Raitrack s Safety Decision Framework Quantitative toerabiity eves set for: workers, passengers, pubic In ALARP region, weigh costs and benefits Two Vaues of Preventing a Fataity: 1.15m for singe fataities 3.22m for mutipe fataities or where risks cose to intoerabe Safety measured in equivaent fataities: 1fataity = 10 major injuries = 200 minor injuries

9 S&SD Safety Risk Mode System wide risk assessment Wi underpin Raitrack s safety case Structured representation of causes and consequences of potentia accidents arising from the operation & maintenance of Raitrack infrastructure Exposed popuations are: Passengers Workers Members of Pubic

10 Safety Risk Mode: Scope A events that can resut in harm to peope from the operation and maintenance of the RCI Train Accidents (ow frequency high consequence) eg: Coisions Deraiments Movement Accidents eg: Passengers faing/injured whie boarding/aighting from trains train-crew struck/crushed by train Non-movement Accidents eg: Sips, trips and fas on patforms worker trapped in machinery

11 Hazardous Events and Precursors A Hazardous event is an event which has the potentia to ead directy to death or injury, eg coision A precursor (cause) is a system or sub system faiure, component faiure, human error or physica effect, which coud individuay or in combination with other precursors resut in the occurrence of a hazardous event Exampe precursors: broken rai, SPAD, dragging brakes

12 Identification of hazardous events Iterative process using 18 generic injury mechanisms, eg: Eectric shock Being crushed Faing Being hit Being trapped Resuts of this were then checked against: Previous studies carried out by the industry A review process within S&SD

13 Identification of hazardous events This iterative process identified 110 hazardous events These events were then aocated to either: Train accidents (24) Movement accidents (32) Non-movement accidents (54)

14 Mode Deveopment Faut trees of Hazardous Events deveoped to eve supportabe by current data sources Event Trees for Hazardous Events incuding: Different types of track & infrastructure features Different times of day Different passenger oadings Other factors which can ead to significanty different outcomes e.g: Is there a reease of toxic or fammabe goods? Is there a fire?

15 Mode Exampe Does train maintain cearances? Y/N Does train obstruct an adjacent ine? N/Y Is there a coision with train on the adjacent ine? N/Y Faut Sequence Frequency (Events/yr) Consequences (Eq fataities/ Event) Risk (Equivaent fataities/yr) Y EXAMPLE FAULT TREE (not fuy deveoped) Faut Sequences Hazardous event definition Passenger train deraiment 0.25 N Deraiment due to roing stock fauts Deraiment due to track fauts Deraiment due to running into obstructions Deraiment due to overspeeding N 0.5 N Broken rai eading to deraiment Bucked rai eading to deraiment Track twist eading to deraiment Precursors Y 0.2 Y EXAMPLE EVENT TREE (not fuy deveoped) Coective Risk = 1.75 RELATIONSHIP BETWEEN FAULT TREE AND EVENT TREE ANALYSIS

16 Deveopment of SRM database Project Database that contains records on: Faut Tree cause precursor data Event Tree consequence precursor data Event Tree consequence data These records contain detais: Assumptions Derivations References

17 Mode outputs The mode produces: The frequency of the hazardous event per year The risk in terms of equivaent fataities per year Using RiskVu we are abe to anayse the mode s resuts to: Identify the risk profie of the hazardous events The risk contribution from individua precursors The risk contribution from groups of precursors Carry out risk sensitivity to changes in data Produce F-N curves for the hazardous events

18 Risk profie (equivaent fataities/year >1) HEM 25 Adut trespasser struck/crushed whie on the RCI HEN 14: P a s s e nge r s ips, trips a nd fa s HET 10: P a s s e nge r tra in c o is io n with ro a d ve hic e o n e ve c ro s s ings HET 1: Cois ion between two pas senger trains (o ther than in s tatio ns) HEN 24: Wo rker s ips, trips and fas (<2m) HEM 27: MOP pedestrian struck/crushed by train o n eve cro ss ing HET 12: Deraiment of passenger train (other than in station) HEN 38: Adut trespasser eectric shock - contact with conductor rai HEM 9: P assenger fa/injured whie boarding or aighting train Hazardous event HEM 2: P as s enger fas fro m train in running HEM 26: Chid trespasser struck/crushed whie on the RCI HEM 8: P as s enger fas fro m patfo rm and s truck by train HEM 12: Passenger trespasser struck whie crossing track at station HEN 45: M OP fa fro m o uts ide o nto R C I HEN 42: Chid trespasser eectric shock - contact with conductor rai HEM 28: MOP pedes trian s truck/crus hed by train o n fo o tpath cro s s ing HET 13: Deraiment of non-passenger train (other than in station) HEN 37: Adut trespasser eectric shock - contact with OHL HEN 21: Worker struck/crushed by structura coapse or arge object HEM 19: Worker struck / crushed by train HEM 6: P assenger fas between train and patform HEM 30: M OP fa whie riding ie ga y o n tra in HEN 10: P assenger eectric shock at station (Conductor rai) HET 9: C o is io n with buffe r s to ps HET 2: Coisio n between a pass enger train and no n-pass enger train (o ther than in s tatio ns ) Risk (equivaent fataities/year)

19 Risk profie: train accidents HET 10: Passenger train coision w ith road vehice on eve crossings HET 1: Coision betw een tw o passenger trains (other than in stations) HET 12: Deraiment of passenger train (other than in station) HET 13: Deraiment of non-passenger train (other than in station) HET 9: Coision w ith buffer stops HET 2: Coision betw een a passenger train and non-passenger train (other than in stations) HET 11: Non-passenger train coision w ith road vehice on eve crossings Hazardous events HET 16: Abnorma dynamic forces e.g. Abnorma deceeration HET 18: Fire on passenger train (other than in station) HET 6: Coision betw een tw o passenger trains in station (permissive w orking) HET 20: Fire on freight train (other than in station) HET 24: Exposion on freight train HET 14: Deraiment of passenger train in station HET 3: Coision betw een tw o non-passenger trains (other than in stations) HET 15: Deraiment of non-passenger train in station HET 22: Structura coapse at station HET 21: Train crushed by structura coapse or arge object (other than in station) HET 23: Exposion on passenger train HET 17: Fire on train passenger train in station Risk (equivaent fataities/year)

20 Risk profie: movement accidents Hazardous event HEM 27: MOP pedestrian struck/crushed by train on eve crossing HEM 9: Passenger fa/injured whie boarding or aighting train HEM 2: Passenger fas from train in running HEM 8: Passenger fas from patform and struck by train HEM 28: MOP pedestrian struck/crushed by train on footpath crossing HEM 19: Worker struck / crushed by train HEM 6: Passenger fas between train and patform HEM 30: MOP fa whie riding iegay on train HEM 3: Passenger struck whie eaning out of train HEM 10: Passenger hit by object whie on patform HEM 16: Train crew fa/injured whie boarding or aighting train HEM 14: Train Crew struck/crushed by train HEM 7: Passenger fas out of train onto track at station HEM 20: Worker struck by fying object HEM 5: Train door coses on passenger HEM 11: Passenger struck whie crossing track at station on crossing HEM 23: Train door coses on rai workers HEM 21: Worker fas between train and patform HEM 4: Passenger struck by object through train window HEM 13: Train overcrowding HEM 22: Worker/train crew fas out of train onto track at station HEM 18: Train Crew hit by object through train window HEM 24: Worker struck whie eaning out of on-track machine/vehice HEM 17: Train Crew struck whie eaning out of train HEM 1: Evacuation foowing stopped train HEM 32: MOP struck by objects from RCI HEM 15: Train Crew fas from train in running HEM 29: MOP outside RCI struck/crushed as a resut of RCI operations Risk (equivaent fataities /year) 5

21 Risk profie: non - movement accidents HEN 14: Passenger sips, trips and fas HEN 24: Worker sips, trips and fas (<2m) HEN 45: MOP fa from outside onto RCI HEN 21: Worker struck/crushed by structura coapse or arge object HEN 10: Passenger eectric shock at station (Conductor rai) HEN 25: Worker sips, trips and fas (>2m) HEN 13: Passenger fas from patform onto to track (no train present) HEN 30: Worker eectric shock (Conductor rai) HEN 51: MOP eectric shock - contact with OHL HEN 26: Worker struck/ crushed by non-train vehice Hazardous events HEN 5: Exposion at Station HEN 49: MOP exposed to exposion on RCI HEN 22: Worker trapped in machinery HEN 46: MOP sip, trip or fa on eve crossing HEN 29: Worker exposure to hazardous substances HEN 52: MOP eectric shock - contact with conductor rai HEN 28: Worker exposure to arcing HEN 33: Worker asphyxiation/ drowning HEN 27: Worker burns HEN 31: Worker eectric shock (OHL) HEN 32: Worker eectric shock (Non-traction suppies) HEN 35: Worker invoved in road traffic accident whie on the RCI HEN 54: MOP exposed to hazardous substances eakage on RCI HEN 20: Train Crew eectric shock - Overhead ine HEN 23: Worker trapped / crushed or hit whie on patform area HEN 9: Passenger eectric shock at station (OHL) Risk (equivaent fataities/year)

22 Risk profie: trespass HEM 25 Adut trespasser struck/crushed whie on the RCI HEN 38: Adut trespasser eectric shock - contact with conductor rai HEM 26: Chid trespasser struck/crushed whie on the RCI HEM 12: Passenger trespasser struck whie crossing track at station Hazardous events HEN 42: Chid trespasser eectric shock - contact with conductor rai HEN 37: Adut trespasser eectric shock - contact with OHL HEN 41: Chid trespasser eectric shock - contact with OHL HEN 36: Adut trespasser fas whie inside RCI HEN 40: Chid trespasser fas whie inside RCI HEN 43: Chid trespasser eectric shock - contact with non-traction suppies HEN 39: Adut trespasser eectric shock - contact with non-traction suppies Risk (equivaent fataities/year)

23 Exampe Uses The mode can be used to respond to questions such as: What is the risk contribution of track twist to passenger train deraiment? How much woud the overa risk from deraiment increase given a 50% increase in the frequency of track twists? What is the current eve of risk reating to the operation of road vehice eve crossings?

24 Where next? Risk profie on Raitrack infrastructure Risk assessment for Raitrack s safety case Avaiabe to RG members Reguar risk profie buetins Identify gaps in risk contro, sensitivity anaysis, cost benefit assessments Inform S&SD activities: Raiway Group Safety Pan, Group Standards & audit programme