annex e hazard log - national infrastructure planning · annex e hazard log. highways agency – m4...

HIGHWAYS AGENCY – M4 JUNCTIONS 3 TO 12 SMART MOTORWAY

ENGINEERING AND DESIGN REPORT ANNEXES HAZARD LOG AND HAZARD LOG REPORTANNEX EFEBRUARY 2015 UPDATED JULY 2015

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Annex E Hazard Log



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EXECUTIVE SUMMARY

Introduction

The M4 J3 - 12 Smart Motorway (M4 J3-12 Sm) scheme will be implemented on the M4 betweenJunction 3 (J3) and Junction 12 (J12). This document is the hazard log report for the implementationof the M4 J3-12 Sm scheme at Stage Gate Assessment Review (SGAR) 3.

Its purpose is to provide documentary evidence that the relevant hazards have been identified andassessed for the M4 J3-12 Sm scheme. This has been achieved by ensuring that:

An appropriate process has been used for identifying hazards and populating the hazard log;

High scoring hazards (i.e. those with the greatest level of risk) have been identified andassessed;

Hazards related to specific populations (i.e. on road resources / maintenance workers) havebeen identified and assessed.

The scope of this hazard log report is the assessment of risk between the baseline and with Smoperational for the M4 J3-12.

The highest risk hazard scores were reviewed at the Project Safety Control Review Group (PSCRG)on 12th September 2013 [15], 28 November 2013 [16], 11 December 2014 [18] and 5 February 2015[19]. As the design develops, additional data becomes available and assumptions change, riskassessments will be reviewed and the hazard log updated.

Conclusions

The hazard analysis work undertaken to SGAR3 leads to the conclusion that, based on the All LaneRunning (ALR) design requirements, the M4 J3-12 Sm scheme is likely to be no worse in terms ofsafety performance than the baseline due to:

A reduction in risk for 13 of the 17 highest scoring existing motorway hazards (i.e. those witha risk score of E08/S08 and above), due to a controlled environment being provided through acombination of regularly spaced mandatory speed signals, speed enforcement, andcomprehensive CCTV coverage.

One highest scoring new hazard is introduced (H152 Vehicle recovered from ERA – (E8.00).

Two existing highest scoring hazard increase in risk

Status: There is a PSCRG to be held on 5th February 2015. This report has beenupdated with the assumption that any hazards to be reviewed at the PSCRG will beendorsed. This status box will be removed before final issue.



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o H135 Vehicle stops in running lane - Off peak (Event) (E07.50 to E08.00)

o H149 Vehicle drifts off carriageway (i.e. leaving the carriageway as a result of theroad environment) (E08.00 to E08.10)

One hazard has been eliminated from the hazard log

o H62 On road resources work unprotected - S06. On road resources always workunder protection from either the Traffic Officer Vehicle (TOV) or Emergency TrafficManagement (ETM)

Calculations show that the total score for ‘after’ represents approximately a reduction ofrisk of 18% when compared with the safety baseline (no motorway incident detection andautomatic signalling queue protection).

This analysis suggests that the scheme is likely to meet its road user safety objective.

A more detailed assessment of road worker safety has been undertaken by the scheme, concludingthat it is likely that the road worker safety objective for maintainers will be achieved; however this canonly be confirmed once the Maintenance and Repair Strategy Statement (MRSS) is completed andsigned off.

It is noted that when comparing the predicted reduction in risk with the actual motorway with MIDAS(10% safety benefit compared to the baseline) the scheme would still expect to see a reduction in riskof approximately 8%.

The outcomes of the hazard log summarised within this hazard log report are generally in line with thegeneric ALR hazard log. Despite the use of numbers the risk score is at best semi-quantitative anddoes not provide an absolute measure of risk.

Recommendations

The hazard log will be updated as and when required during the scheme design process. In particularit will be updated if either of the following occurs:

Future design changes, for example if mitigations identified to protect maintainers change.

If significant new evidence emerges which could impact on the hazard scores, for examplemonitoring results from similar Sm schemes.

The hazard log report will be periodically reviewed and re-issued if there are any significant changesto the hazard log, at SGAR5.



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CONTENTS: EXECUTIVE SUMMARY............................................................... I

1 INTRODUCTION ..................................................61.1 DOCUMENT PURPOSE 6

1.2 DOCUMENT SCOPE 6

1.3 DESCRIPTION OF SCHEME 6

1.4 THE KEY SAFETY CHALLENGES 6

2 HAZARD LOG SCORING ....................................82.1 POPULATION OF THE HAZARD LOG 8

2.2 KEY ASSUMPTIONS 9

2.3 SAFETY BASELINE AND OBJECTIVES 11

2.4 KEY HAZARDS 12

3 HAZARD LOG ACTIONS ................................... 153.2 COMPARISON WITH GENERIC SAFETY ASSESSMENT 21

3.3 HAZARDS RELATED TO SPECIFIC POPULATIONS 22

3.4 VERIFICATION OF HAZARD LOG SCORES 22

4 FUTURE HAZARD LOGACTIVITIES/RECOMMENDATIONS .................. 24

5 REFERENCES ................................................... 25

ANNEXES: ANNEX A: GLOSSARY OF TERMS ANDABBREVIATIONS

ANNEX B: SIGNIFICANT ASSUMPTIONSDIFFERENT TO GENERIC

ANNEX C: MEDIUM SCORING HAZARDS

ANNEX D: SPECIFIC POPULATION HAZARDS

ANNEX E: SCORING PARAMETERS AND INDICES

ANNEX F: IMPLICATIONS OF M42 SMARTMOTORWAY THREE YEAR SAFETYREVIEW

ANNEX G: ALR DESIGN REQUIREMENT



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LIST OF FIGURES: FIGURE 2-1: HAZARD LOG DEVELOPMENT .............................9

FIGURE 5-1: : HAZARD SCORES ARE CALCULATED ASFOLLOWS: ........................................................ 34

FIGURE 5-2: ILLUSTRATIVE DRAWING OF ALR ..................... 41

LIST OF TABLES: TABLE 2-1: M4 J3 TO J12 HAZARD LOG KEYASSUMPTIONS ...................................................9

TABLE 2-2: MAIN DIFFERENCES BETWEEN M4 J3-12AND GENERIC ASSUMPTIONS ........................ 10

TABLE 3-1: HIGHEST SCORING HAZARDS FOR M4 J3-12 SM SCHEME................................................. 16

TABLE 5-1: ASSUMPTIONS USED WITH HIGHEST RISKSCORE .............................................................. 28

TABLE 5-2: MEDIUM SCORING HAZARDS .............................. 29

TABLE 5-3: MOST SIGNIFICANT AND RELEVANTHAZARDS THAT APPLY TO ON ROADRESOURCES .................................................... 31

TABLE 5-4: MOST SIGNIFICANT AND RELEVANTHAZARDS THAT APPLY TOMAINTENANCE WORKERS .............................. 33

TABLE 5-5: EVENT FREQUENCY INDICES .............................. 35

TABLE 5-6: STATE FREQUENCY INDICES (LIKELIHOODSCORE) ............................................................. 35

TABLE 5-7: COLLISION INDICES (RATE/PROBABILITYTHAT HAZARD LEAD TO AN ACCIDENT) ....... 36

TABLE 5-8: SEVERITY INDICES (SEVERITY OFACCIDENT SCORE) .......................................... 36

TABLE 5-9: AFTER SCORING VALUES .................................... 37

TABLE 5-10: ANALYSIS OF PIA FIGURES - 60%REDUCTION IN RISK ........................................ 38



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1 INTRODUCTION

1.1 Document Purpose

The purpose of this document is to provide documentary evidence that the relevant hazards havebeen identified and assessed for the M4 J3-12 Smart Motorway (M4 J3-12 Sm) scheme.

1.2 Document Scope

The M4 J3-12 Sm scheme will be implemented on the M4 between Junction 3 (J3) and Junction 12(J12). This document is the hazard log report for the implementation of the M4 J3-12 Sm scheme atStage Gate Assessment Review (SGAR) 3.

The report has been produced to accompany the hazard log for the M4 J3-12 Sm scheme, to assist inachieving SGAR3 and contains a snapshot of the hazard log as of April 2014.

The scope of this hazard log report is the assessment of risk between the baseline and with Smoperation for the M4 J3-12 Sm scheme.

This report contains the following:

A description of the process followed to populate the scores for each hazard;

A list of the key assumptions that underpin the hazard analysis;

A list of the high scoring hazards, i.e. those that have been identified as having the greatestrisk associated with them;

Where necessary additional information on the risk assessment process;

Outstanding actions for consideration during subsequent project control framework (PCF)stages.

1.3 Description of Scheme

For further background information on the M4 J3-12 Sm scheme, refer to the Highway Agency’s ClientScheme Requirements product.

1.4 The key safety challenges

The key safety challenges for the M4 J3-12 Sm scheme relate to:

Status: There is a PSCRG to be held on 5th February 2015. This report has beenupdated with the assumption that any hazards to be reviewed at the PSCRG will beendorsed. This status box will be removed before final issue.



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The on-road operation (Traffic Officer Service and core responders) implications from havingno hard shoulder.

The acceptance of the All Lane Running (ALR) design by emergency services and other keystakeholders.

The impact on maintenance access and existing maintenance operations through the removalof the hard shoulder.

The impact of the increased technology equipment and associated infrastructure that isrequired to safely operate an Sm scheme.



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2 HAZARD LOG SCORING

2.1 Population of the hazard log

To populate the hazard log for the M4 J3-12 Sm scheme a list of assumptions was first produced.These assumptions were derived using the generic hazard log and from data collated from the Area 3Asset Support Contract (ASC) and Area 5 DBFO contract.

Once the assumptions had been determined, individual risk assessments for each hazard in thehazard log were carried out using the methodology described in Annex E (see also the project safetyrisk management work instructions, interim advice note (IAN) 139/11 [7] [8]). All the hazards in thegeneric Sm hazard log relevant to ALR1 have been used at this stage with the exception of hazardH62 On-road resources work unprotected (S06.00), which has been deleted as on road resources(traffic officers) are not permitted by their procedures to work unprotected. No new hazards have beenincorporated into the hazard log at SGAR3.

Following the publication of the M42 Sm three year safety review [1] greater assurance is nowavailable that a scheme conforming to IAN 111/09 [4] can achieve considerable safety benefits (seeAnnex F). It can be seen from the description of ALR in Annex G that there are differences betweenALR and IAN 111/09 (for example permanent conversion of the hard shoulder to a running lane).However, there are key elements in common, most notably variable mandatory speed control andspeed enforcement, consequently hazards that are impacted by these elements should see aconsiderable improvement in risk. Therefore, the hazard log supporting IAN 161/13 ALR builds on thehazard log that supports IAN 111/09.

The process for the development of the M4 J3–12 Sm hazard log is shown overleaf in Figure 2-1. TheM4 J3–12 hazard log is based on the generic IAN 161/13 hazard log. It also takes account of workfrom other ALR schemes, e.g. M1 J28–31, M1 J32–35a and M25 J23–27. This provides confidencethat the assumptions and risk assessments, and therefore the hazard log, are robust and consistentwith other ALR schemes currently designed.

1 The Smart Motorways generic hazard log includes hazards relating to hard shoulder opening as ithas been used previously for Hard Shoulder Running (HSR) schemes. These hazards are notrelevant to an ALR scheme and hence have not been used.



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Figure 2-1: Hazard log development

The significant hazard risk scores were reviewed by the Project Safety Control Review Group(PSCRG) on 12th September 2013 [15], 28 November 2013 [16], 11 December 2014 [18] and 5February 2015 [19].

2.2 Key assumptions

The hazard log contains a number of assumptions on which the risk assessments are based. Keyassumptions are listed in Table 2-1:

Table 2-1: M4 J3 to J12 hazard log key assumptions

Assumption

Scheme length 31.88 miles (51.31 km)

Distance betweenrefuges

Average 1.14 miles (1.85km)

Vehicles per day 123,795 (average annual weekday traffic 2012)

Signal gantryspacing

Average 900m (0.9km)

Junction layouts The design provides Through Junction Running (TJR) at junctions 4, 5, 6, 7,8/9,11 as directed by Roads Programme Steering Group (RPSG).



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Assumption

Gradients Gradients are not expected to have an impact on the operation or safety of theM4 J3-12 Sm scheme.

Concrete barrier Concrete barrier throughout on a hardened central reserve.

Overrun design Risk will be mitigated through further analysis using Civils Technical AppraisalGroup ‘Overrun design tool’ (tool was submitted to the National Safety ControlReview Group (NSCRG) where it was endorsed at the 8th November 2012meeting).

Remote controltraffic management(TM) signs

Provided in central reserve and verge associated with fixed taper points,eradicating carriageway crossings for deployment and removing the need forimpact protection vehicle in lane four for offside signs as detailed in thescheme Maintenance and Repair Strategy Statement (MRSS).

Remote diagnostics Will be utilised to limit visits to technology (variable message signs (MS4s andMS3s), lane specific signals and CCTV.

Signal sequencingrules

Changes to signal sequencing rules to incorporate MS4s with lane specificsignalling will be completed in time for implementation on the scheme.

Signals During -ALR operation signals will be used to display speed limits duringdeployment and removing of TM.

Most of the assumptions are in line with those used in the generic ALR demonstration of meetingsafety objective report [10].

The most significant differences between the M4 J3 to J12 and generic assumptions are listed inTable 2-2 below:

Table 2-2: main differences between M4 J3-12 and generic assumptions

Assumption M4 J3-12value

Genericvalue

Affectedhazards

Difference to genericassumption

A53 Percentage of trafficvolume during peakperiods

29% 20.00% H91

H135

H135

Site specific data showshigher percentage of peaktraffic volume compared togeneric assumption.



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Assumption M4 J3-12value

Genericvalue

Affectedhazards

Difference to genericassumption

A59 Percentage peak periodby time

17% 29% H76 The generic figure is basedon an assumption of 7hr ofpeak period a day. The sitespecific value was based onthe opening hard shoulderthreshold on IAN 111/09schemes.

A71 Vehicles per day permotorway mile

123,795 130,000 H37

H91

H149

The generic figure is basedon an assumption of 7hr ofpeak period a day. The sitespecific value was based onthe opening hard shoulderthreshold on IAN 111/09schemes.

2.3 Safety baseline and objectives

To quantify the hazard assessment it is necessary to define a safety baseline against which thechange in risk is to be measured. The derivation of the safety baseline is described in the safety plan[9].

As MIDAS queue protection is installed on the scheme the safety baseline is:

110% of the number (averaged per annum) of Fatal and Weighted Injury (FWI) casualties,and the rate of FWIs per billion vehicle miles per annum, averaged for the three years priorto the installation of the scheme.

The scheme will satisfy the safety objective for road users if both of the two key indicators above aredemonstrated to be no worse than the safety baseline for the three years after full scheme opening. Inaddition no population (e.g. car drivers, pedestrians, HGV drivers and motorcyclists) isdisproportionately adversely affected in terms of safety and risk to each population remains tolerable.



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There will be no specific numerical safety objective set for road workers. This risk will be managed inaccordance with the requirements of the Health and Safety at Work Act and subsidiary regulations tobe So Far As Is Reasonably Practicable (SFAIRP)2.

2.4 Key hazards

2.4.1 Overview

The scoring exercise and the hazard log structure enables the safety team to target further safetyappraisal at those issues that pose the greatest risk and where further action is likely to have thegreatest safety impact. The highest risk hazards were considered to be those:

With a ‘before’ or ‘after’ risk score of 8.0 or more.

With respect to the existing risk and before implementation of a scheme existing motorway hazardswith a score of 8.0 or more account for nearly 89% of the existing risk on the scheme. Similarly,existing hazards (before implementation of the scheme) with a score of 7.5 or more account for 95%of the existing risk and hazards with a score of 7.0 or more account for 99% of the existing risk (seeAnnex C).

In total new hazards resulting from the implementation of the scheme are expected to addapproximately 4% to the existing risk (these hazards are associated with the operation of the ERAs).Therefore, to match or better the safety baseline the risk associated with existing hazards mustdecrease by more than 4% as a result of the scheme.

The project has also considered the higher scoring hazards affecting key specific road user groups:

On road resources (traffic officers);

Maintenance workers.

The ‘Before’ and ‘After’ scores associated with the highest risk on road resource (traffic officers) andmaintenance workers hazards are presented in Annex D.

2 Currently there is no numerical objective or target for Road Worker accidents on SM projects andthe risk is managed in accordance with SFAIRP. The Highways Agency's “Aiming for Zero” strategy isintended to be a catalyst for further positive action to reduce the risk to Road Workers. One part of thestrategy aims to eliminate all fatalities and serious injuries to Road Workers maintaining the HighwaysAgency’s road network. The Highways Agency does have a target for road worker safety (this beingan Accident Frequency Rate (AFR) of 0.1 incidents reportable under the Reporting of Injuries,Diseases and Dangerous Occurrences Regulations 1995 (RIDDOR) per 100,000 hours worked andpresented as a 12 month rolling average) and that the scheme, through committing to manage risksfor road workers so far as is reasonably practicable, is contributing to achieving this target.



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The parameters that make up each risk score are presented in Annex E.

2.4.2 Assessment of ‘ALR’ against the baseline

Road user safety objective

At this stage the hazard analysis work leads to the conclusion that the safety risk of the M4 J3-12 Smscheme is likely to be no worse than the baseline due to:

A reduction in risk for a significant number (15) of the highest scoring (E08/S08 and above)existing motorway hazards (17), due to a controlled environment being provided through acombination of regularly spaced mandatory speed signals, speed enforcement, andcomprehensive CCTV coverage;

One highest scoring new Sm hazard is introduced (H152 Vehicle recovered from ERA –(E8.00));

Two existing highest scoring hazard increase in risk

o H135 Vehicle stops in running lane - off peak (Event) (E07.50 to E08.00);

o H149 Vehicle drifts off carriageway (i.e. leaving the carriageway as a result of theroad environment) (E08.00 to E08.10).

Calculations show that the ‘total score’ for ‘after’ represents approximately a reduction of riskof 18% when compared with the safety baseline (no MIDAS queue protection).

This analysis suggests that the scheme is likely to meet its road user safety objective.

It is noted that when comparing the predicted reduction in risk with the actual motorway with MIDAS(10% safety benefit compared to the baseline) the scheme would still expect to see a reduction in riskof approximately 8%.

Road worker safety objective

The most significant hazards relating to on road resources (traffic officers) and maintenance workersare listed in Annex D.

The generic ALR safety assessment, detailed within the Demonstration of Meeting Safety Objective(DMSO) report [10], suggested that without the implementation of mitigation measures it wasdetermined that ”it cannot be concluded that the safety objective is likely to be achieved or that therisk is managed [so far as is reasonably practicable] SFAIRP”.

Various national tasks are being progressed to deliver additional mitigation measures which providefurther safety benefits to road workers. These include:



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Signalling through road works (inc. 40 mph speed limits through deployment, during andremoval of TM);

Remote interrogation of VMS and lane specific signals (over IP);

IAN 150/12 (published in November 2012), Temporary Traffic Management Signing:Simplification of lane change zone signing for relaxation schemes;

The principles for determining optimum fixed taper locations for the deployment of trafficmanagement;

The use of remote control TM signs and assessing the potential type of remote control TMsign;

The use of Rigid Concrete Barrier (RCB) throughout the scheme length;

Rationalising of planned maintenance activities into other planned works.

The current status of the work being undertaken on the various national road worker safety workpackages is described in more detail in the ALR - demonstration of meeting safety objective report[10].

Review of the Traffic Officer hazards in Annex D suggests that the road worker safety objectiveshould be achieved for Traffic Officers. H34 “Incident management” – rolling block has increased fromE6.0 to E6.5. This is a ‘Low Risk’ score classification and has a lower score when compared to otherTraffic Officer hazards.

2.4.3 Notes on assessment methodology

Despite the use of numbers the risk score is at best semi-quantitative and does not provide anabsolute measure of risk. The methodology is designed to place each hazard into one of a number ofbands so that it can be seen clearly which hazards are considered to present the greatest risk.

This approach also facilitates the calculation of risk changes that a project brings about, thus enablingan assessment to be made as to whether a project has achieved its safety objective. To completesuch an assessment each hazard must be reviewed and the impact that the project has on its scoreconsidered. By adding together the impact of all such risk changes, the overall change in risk that theproject brings is calculated.

However, the use of semi-quantitative approach means that undue weight should not be placed onthe quoted change in risk as it is only indicative of the change in risk for the scheme as a whole.Evidence from the M42 Sm scheme indicates that there is a good correlation between the predictedsafety risk assessment of the hazard log and the actual safety performance and type of accidents,although it should be recognised that the hazard log is not an accident (level) prediction tool.



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3 HAZARD LOG ACTIONS3.1.1 High scoring hazards

The highest scoring hazards are listed below (S08/E08 and above). These drive the hazard analysissummarised in section 2 and represent approximately 89% of the total baseline risk. When reviewingTable 3-1 “Change in risk relative to before”:

‘0.0’ means no change in risk for M4 J3 to J12 Sm (yellow)

‘-‘ means a reduction in risk score for M4 J3 to J12 Sm (green)

‘+’ means an increase in risk score for M4 J3to J12 Sm (red)

When reviewing Table 3-1 the difference between a M4 J3-12 risk score and a generic risk score ishighlighted as follows:

Higher risk score in generic hazard log (blue)

Lower risk score in generic hazard log (pink)

The highest scoring hazards were reviewed at PSCRG on 14 May 2013, 12 September 2013 (focuson M4 J8/9-12), 28 November 2013 (focus on M4 J8/9-12), 11 December 2014 [18] and 5 February2015 [19]. As the design develops, additional data becomes available and assumptions change, therisk assessments will be reviewed and the hazard log updated.



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Table 3-1: Highest scoring hazards for M4 J3-12 Sm scheme

Hazard Description

M4 J3 to J12 Generic ALR

Reason fordifference in M4 J3to J12 and genericrisk scores

Risk scorebefore

Change in riskrelative tobefore

Risk afterscore

Risk scorebefore

Change inriskrelative tobefore Risk after score

H37Individual vehicle is driventoo fast

S09.00 - 0.25 S08.75 S09.00 - 0.23 S08.77Slight differencedue to higher peaktraffic volumes

H67Pedestrian in running lane- live traffic

E08.50 0.00 E08.50 E08.50 0.00 E08.50 No difference

H138Driver fatigued - unable toperceive hazardseffectively

E08.90 - 0.01 E08.89 E09.00 - 0.01 E08.99

Presence ofmotorway servicearea (MSA)between J11 andJ12, which shouldhelp decrease driverfatigue.

H76Rapid change of generalvehicle speed

E08.50 - 0.34 E08.16 E08.50 - 0.34 E08.16 No difference



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Hazard Description



Risk scorebefore


Risk afterscore

Risk scorebefore


H135Vehicle stops in runninglane - off peak (Event)

E07.50 + 0.50 E08.00 E07.81 + 0.50 E08.31

Lower score due tolower percentagetraffic off-peakcompared togeneric case

H52Maintenance workerssetting up and taking downwork site

S07.82 - 0.06 S07.76 S08.00 0.00 S08.00

Hazard scoreidentified fromHighways Agencyroad worker safetyassessment tool



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Hazard Description



Risk scorebefore


Risk afterscore

Risk scorebefore


H149

Vehicle drifts offcarriageway (i.e. leavingthe carriageway as a resultof road environment)

E08.00 + 0.1 E08.1 E08.00 0.00 E08.00

Slight increase inrisk as some trafficis travelling nearerthe edge of thecarriageway and atnational speedduring off peaktimes. PSCRGproposed that thesame change to therisk score should beconsidered for thegeneric ALR hazardlog.

H152Vehicle recovered fromERA

N/A N/A E08.00 N/A N/A E08.00 No difference

H89Sudden weaving at exitpoint




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Hazard Description



Risk scorebefore


Risk afterscore

Risk scorebefore


H54Motorcycles filter throughtraffic


H13Driver loses control ofvehicle


H120Vehicle rejoins runninglane


H121Vehicle reversing alongexit slip


H103 Unsafe lane changing E08.00 - 0.17 E07.83 E08.00 - 0.17 E07.83 No difference

H11Driver ignores closedlane(s) signals that areprotecting an incident

E08.00 0.00 E08.00 E08.00 0.00 E08.00 No difference

H112Vehicle enters maincarriageway unsafely

E08.00 - 0.20 E07.80 E08.00 - 0.20 E07.80

No change noted,based upon theoptimum designbeing provided ateach merge location



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Hazard Description



Risk scorebefore


Risk afterscore

Risk scorebefore


along with use ofthe overrun designtool

H91 Tail gating S08.50 - 0.30 S08.20 S08.50 -0.30 S08.20 No difference

H154Vehicle stopped on hardshoulder (D3M) or verge(ALR)

S08.00 - 1.0 S07.00 S08.00 - 1.5 S06.50

Hard shoulderretained through J3,4b, 10, 12 (genericdesign assumesTJR throughout)



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3.2 Comparison with generic safety assessment

Table 3-1 shows that for most of the highest scoring hazards of the M4 J3–12 Sm scheme, the riskscore for the baseline and the change in risk for the implementation of Sm is the same as that in thegeneric ALR hazard log. However there are four hazards where the risk score from the M4 J3–12 Smscheme is lower than the generic risk score.

For H37 ‘Individual vehicle is driven too fast’ the risk reduction for M4 J3-12 Sm is slightly greater thanfor a generic ALR scheme because of higher peak traffic volume when the benefit of mandatoryspeed limits and the provision of a controlled environment are greatest.

For H138 Driver fatigued - unable to perceive hazards effectively’ the ‘before’ score is slightly lowerthan the generic score due to the presence of a motorway service area (MSA) between J11 and J12,which should help decrease driver fatigue.

For H135 ‘Vehicle stops in running lane - off peak’ the risk score for M4 J3–12 Sm is lower than thescore in the generic ALR hazard log as a result of lower off peak traffic flows.

For H52 ‘Maintenance workers setting up and taking down work site’ the risk score is also slightlylower. The hazard score is from applying the Highways Agency road worker safety assessment tool,which shows that with mitigations such as RCB and remote control TM signing the risk from thishazard remains broadly unchanged from the level before implementation of Sm.

The risk score for M4 J3-12 is slightly higher for H149 ‘Vehicle drifts off carriageway (i.e. leaving thecarriageway as a result of road environment)’. The increase in risk for this hazard (compared to ‘nochange’ in the generic ALR case) was endorsed at the 12th September 2013 PSCRG. PSCRGproposed that the same change to the risk score should be considered for the generic ALR hazardlog.

The change score for H11 ‘Driver ignores closed lane(s) signals that are protecting an incident’ hasbeen changed from a ‘-0.2’ to a ‘0’ since the publication of the SGAR 2 version of this hazard logreport in line with changes to the generic ALR hazard log. The change in score reflects results frommonitoring of the M25 ALR sections, which show that at times significant number of drivers ignoreRed X lane closure signals. The score changes was endorsed by the PSCRG on 11 December 2014.

The risk reduction for H154 ‘Vehicle stopped on hard shoulder (D3M) or verge (ALR)’ is lower for M4J3-12 Sm compared to the generic ALR hazard log as a hard shoulder is retained through J3, 4b, 10,12, whereas the generic design assumes the provision of Through Junction Running (TJR)throughout).

Hazard H62 ‘On road resources work unprotected’ (S06) has been eliminated from the hazard log. Onroad resources always work under protection from either the Traffic Officer Vehicle (TOV) orEmergency Traffic Management (ETM). This applies to both the current motorway and after ALRimplementation. It is noted that the Highways Agency was recently issued with a Crown Censure – the



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equivalent of a criminal prosecution – for safety failings after the fatality of a Traffic Officer who wasstruck by a vehicle on the M25. The Health and Safety Executive (HSE), which investigated, took thedecision to deliver a Censure after identifying failures in the Highways Agency’s quarterly supervisionchecks at the Dartford outstation. This has been taken into account within the hazard log but is notedthat this incident was due to correct safety procedures not being followed.

Hazard H95 ‘TO/maintainer in running lane’ covers situations where a traffic officer (TO) or maintainercrosses one or several running lanes (e.g. to retrieve debris) which historically would have involvedusing the hard shoulder as a starting point. The generic hazard log assumes that with the introductionof ALR no areas of hard shoulder remain from which to start work and therefore the generic riskassessment for H95 has been revised to take into account that rolling road blocks are now used moreregularly instead of stopping on the hard shoulder and crossing running lanes. The risk from thishazard (H95) has therefore been eliminated from the generic hazard log. However, the M4 J3-12 Smscheme will retain some areas of hard shoulder through junctions 3, 4b, 10 and 12. Therefore, the‘before’ score for H95 has been reduced to an E6.5 (was previously assessed as E8.0 at SGAR 2).The risk from this hazard, although significantly reduced, is not completely eliminated and a residualrisk remains, which is reflected by the risk reduction score of ‘-1.5’ and the ‘after’ score of E5.0. Therisk of H34 ‘Incident management - rolling block’ has increased from E5.0 to E6.0.

3.3 Hazards related to specific populations

The Highways Agency’s Standard for the Safety Risk Assessment on the Strategic Road Network,GD04) defines four populations that must be taken into account when considering what is reasonablyrequired to manage their safety risk exposure [20]. Therefore, in addition to considering the impact ofthe scheme on the safety of all road users, the initial hazard log work has considered the safetyimpact of the scheme for the following specific user groups:

On road resources (traffic officers);

Maintenance workers.

These are largely aligned with populations 1 and 2 (Workers) as defined in GD04. Annex D providesdetails of the assessments. Other populations as set out in the Managed Motorway – All LaneRunning, Demonstration of Meeting Safety Objective Report [10] will be assessed as the designdevelops. It is expected that the risk for these populations is comparable to that of a generic ALRscheme and lower than the baseline D3M risk.

3.4 Verification of hazard log scores

A generic ALR hazard log has been produced during the development of IAN161/12. The hazardscores were verified at a Highways Agency workshop on 1st February 2012. As part of the update toIAN161 and the associated safety documentation a workshop took place on 18th March 2013 to



REV 02 PAGE 23

discuss amendments to hazard scores based upon changes to the IAN161 document. The outcomeis recorded in the ALR DMSO report [10]. IAN 161/13 was published in August 2013 [5].

Work has been undertaken to look at the specific hazards relating to maintenance. A HighwaysAgency workshop took place on 29th February 2012 to discuss progress on managing maintenanceworker safety risk.

The assumptions used in the generic ALR hazard risk scores have been reviewed at a workshopusing M1 J28 to J31 specific data on 29th August 2012, attended by Highways Agencyrepresentatives. The hazard analysis work reported here has been undertaken by members of the M1J28 to J31 Sm project team who have considerable experience of undertaking such assessments onother Sm schemes (including the M42 J3a to J7 and Birmingham Box Sm phases 1, 2 and 3schemes).

PSCRG has reviewed the highest scoring hazard risk scores as detailed in sections 3.1.1 and 3.4.1.This review gives confidence in the conclusion reached that the scheme is likely to meet its safetyobjective.

3.4.1 Actions

The hazard assessment work was supported by PSCRG as follows:

M4 J3-12 Sm, 26 March 2013: Road worker safety assessment – review and endorsement ofresults from road worker safety assessment tool including additional mitigation measures(remotely operated signs, rationalisation of maintenance activities and the deployment ofRCB) to enable the scheme to meet the safety objective [13]

M4 J3-12 Sm, 14 May 2013: Hazard log – significant hazard review [14]

M4 J8-12 Sm, 12 September 2013: Hazard log – significant hazard review [15]

M4 J8-12 Sm, 28 November 2013: Hazard log – significant hazard review [16]

M4 J3-12 Sm, 09 April 2014: PSCRG remit and endorsement of design solutions [17]

M4 J3-12 Sm, 11 December 2014: Hazard log – significant hazard review [18]

M4 J3-12 Sm, 5 February 2015: Hazard log – significant hazard review [19]



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4 FUTURE HAZARD LOG ACTIVITIES/RECOMMENDATIONS

The hazard log will be updated as and when required during the scheme design process. In particularit will be updated if either of the following occurs:

New hazards that are identified as the design develops will be added to the hazard log andtheir risk will be assessed. Additional mitigation measures will be identified where necessary;

Risk assessments of existing hazards will be reviewed and updated as the design develops;

Future design changes, for example if mitigations identified to protect maintainers change;

If significant new evidence emerges which could impact on the hazard scores, for examplemonitoring results from other similar Sm schemes or recommendations from an investigationinto a road worker incident (either on the scheme or another ALR scheme).

The hazard log report will be periodically reviewed and re-issued if there are any significant changesto the hazard log, or through the development phase.



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5 REFERENCES

Note: the documents marked * are available from the “Additional DCO document links” section of theHighways Agency project website http://www.highways.gov.uk/roads/road-projects/m4-junctions-3-12/

[1] M42 MM Monitoring and Evaluation, Three Year Safety Review, HCG, January 2011

[2] Advanced Motorway Signalling and Traffic Management Feasibility Study, A report to theSecretary of State for Transport, DfT, March 2008

[3] Chief Highway Engineer Memorandum 276/11, Managed Motorway Requirements

[4] Interim Advice Note 111/09, Managed Motorways Implementation Guidance, Hard ShoulderRunning

[5] Interim Advice Note 161/13, Managed Motorways - All Lane Running

[6] M4 J3 to J12 Smart Motorway Operating Regime Report

[7] Guidance For Work Instructions 001-004 – Appendices Project Safety Risk Management,IAN139/11*

[8] Managed Motorway Hazard Log Process Document*

[9] M4 J3 to J12 Smart Motorway Safety Plan

[10] 1039092-DMS-017, Managed Motorway – All Lane Running, Demonstration of MeetingSafety Objective Report

[11] M4 J3 to J12 Smart Motorway Maintenance and Repair Strategy Statement

[12] Aiming for Zero - Road Worker Safety Priority Projects

[13] M4 J3-12 Sm PSCRG minutes 26 March 2013

[14] M4 J3-12 Sm PSCRG minutes 14 May 2013

[15] M4 J8-12 Sm PSCRG minutes 12 September 2013

[16] M4 J8-12 Sm PSCRG minutes 28 November 2013

[17] M4 J3-12 Sm PSCRG minutes 02 April 2014

[18] M4 J3-12 Sm PSCRG minutes 11 December 2014

[19] M4 J3-12 Sm PSCRG minutes 05 February 2015

[20] GD04/12 Standard for Safety Risk Assessment on the Strategic Road Network



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Annex A: Glossary of terms and abbreviations

Acronym Description

ALR All lane running

AMI Advanced motorway indicators

ASC Asset Support Contract

CCTV Closed circuit television

CM Controlled Motorways

CR Central reserve

DMSO Demonstration of meeting safety objective

ERA Emergency refuge area

ERT Emergency roadside telephone

FWI Fatal weighted injury

HGV Heavy goods vehicle

HSR Hard shoulder running

IAN Interim advice note

LGV Large goods vehicle

MAC Managing agent contractor ADD ASC?

MIDAS Motorway incident detection and automatic signalling

MRSS Maintenance and repair strategy statement

MSA Motorway service area

MS3 Message sign, mark 3

MS4 Message sign, mark 4

NDDD Network Delivery and Development Directorate

NSCRG National Safety Control Review Group

ORR On-road resource

PCF Project control framework

PIA Personal injury accident

PSCRG Project Safety Control Review Group

PTZ Pan-tilt-zoom

RCB Rigid Concrete Barrier

RCC Regional Control Centre

RPSG Roads Programme Steering Group

SFAIRP So far as is reasonably practicable

SGAR Stage gate assessment review

Sm Smart motorways

TechMAC Technology managing agent contractor



REV 02 PAGE 27

Acronym Description

TJR Through junction running

TM Traffic management

TO Traffic officer

VMS Variable message sign

VMSL Variable mandatory speed limits



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Annex B: Significant assumptions different to generic

Table 5-1 below details some of the key assumptions used for M4 J3-12 Sm scheme. It highlightswhere assumptions differ from those used in the generic hazard log:

1. Decreases in assumption are highlighted in green (-)

2. Increases in assumption are highlighted in red (+)

3. No change in assumption are highlighted in yellow (0)

Table 5-1: Assumptions used with highest risk score

Assumption Reference M4 J3 to J12 Value Generic ALRValue

Difference

A4 - Average duration for a breakdown 50 50 0

A22 - Number of breakdowns per day permotorway mile

1.60 1.56 +0.04

A25 - Number of lane closures per day permotorway mile

0.20 0.22 -0.02

A37 - Percentage of breakdowns that cannotbe fixed on site and require towing

25% 25% 0

A38 - Percentage of breakdowns that fail toreach an ERA

50% 50% 0

A53 - Percentage of traffic volume duringpeak periods

29.40% 20% + 9.40%

A71 - Vehicles per day per motorway mile 123,795 130,000 -6,205



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Annex C: Medium scoring hazards

Further to Table 3-1, the table below contains the medium scoring hazards (E07.5 / S07.5 and E07 /S07). The hazards scoring E07/S07 and above represent 99% of the existing scheme risk. Whenreviewing table A3-1 the following points should be considered:

1. N/A = not applicable is for when a hazard only applies ‘after’ implementation of Sm.

2. Post implementation risk scores: ‘0.0’ means no change in risk (highlighted in yellow).

3. Decreases in hazard risk score are highlighted in green (-)

4. Increases in hazard risk score are highlighted in red (+).

5. ‘Eliminated’ means that the risk has been eliminated.

6. The hazard ID reflects the Sm-ALR hazard ID (generic and for M4 J3 – 12 Sm). Whereapplicable the hazard ID in brackets reflects the numbering that was previously adopted forHSR schemes.

Table 5-2: Medium scoring hazards

HazardBaseline risk

scoreAfter risk

scoreChange with

ALRID Description

H141(H33) HGV-LGV-Bus exits ERA N/A E07.5 New Hazard

H79 Roadworks - long term static S07.5 S07.5 0.0

H113 Vehicle exits ERA N/A E07.5 New Hazard

H110 Vehicle drifts out of lane E07.5 E07.43 - 0.07

H137(H8)

Debris in running lane (being hit or causing unsafemanoeuvre) S07.5 S07.23 - 0.27

H155 Vehicle stops in running lane – Peak E07.0 E07.5 + 0.5

H147(H73) Pedestrians walking in lane 1 (applies to ALR only N/A S07.00 New Hazard

H116 Vehicle misjudges entry to ERA N/A E07.0 New Hazard

H126 Vehicle stopped on slip road (off or on slip) E07.0 E07.10 + 0.1

H122 Vehicle reversing back to exit slip E07.0 E07.06 + 0.06

H32 Health deterioration of vehicle occupant E07.0 E07.05 + 0.05

H42 Lane(s) closed, but driver unable to leave lane and E07.0 E07.0 0.0



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HazardBaseline risk

scoreAfter risk

scoreChange with

ALRID Description

stops

H68 Pedestrian on slip road S07.0 S07.0 0.0

H150(H114)

Vehicle in ERA (or verge) obtrudes into lane 1(applies only to ALR) N/A S07.0 New Hazard

H131 Vehicle suddenly decelerates at end of on slip road E07.0 E07.0 0.0

H36 Incidents or congestion caused in other lanes orcarriageway due to rubber necking S07.0 S06.9 - 0.1

H123 Vehicle reversing up entry slip E07.0 E06.9 - 0.1

H94 TO arrives, but has difficulty containing the scene E07.0 E06.9 - 0.1

H104 Unsafe lane changing in the slip road (both off andon slips) E07.0 E06.86 - 0.14

H77 Reduced visibility due to weather conditions S07.0 S06.8 - 0.2

H99 TOs/emergency services not despatched in atimely manner E07.0 E06.8 - 0.2

H102 Undertaking E07.0 E06.8 - 0.2

H2 Abnormal loads - notifiable E07.0 E06.8 - 0.2

H118 Vehicle on the main carriageway deceleratessuddenly E07.0 E06.7 - 0.3

H30 Group of vehicles drive too fast (in relation toset/not set speed limit) S07.0 S06.7 - 0.3

H143(H55)

Motorcycle stopped next to running lanes (D3M =hard shoulder, M-ALR = verge) S07.0 S05.5 - 1.5

H148(H81) Roadworks - short term static on hard shoulder S07.5 S00.0 Eliminated

H82 Short duration stops / debris removal by TO /maintenance workers S07.0 S00.0 Eliminated



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Annex D: Specific population hazards

When reviewing the following tables for specific users the following points should be considered:

1. ‘0.0’ means no change in risk score (highlighted in yellow)

2. Decreases in hazard risk score are highlighted in green (-)

3. Increases in hazard risk score are highlighted in red (+).

The highest scoring hazards have been listed (E06 and above).

On road resources (traffic officers)

Table 5-3: Most significant and relevant hazards that apply to on road resources

Hazard M4 J3 to J12

ID Description Baselinescore

Change Reason for change

H95TO/maintainerin running lane

E06.5 -1.5

Hazarddecreased

Most work carried out under rolling road block.However, some areas of hard shoulder remain where

TO/maintainer might use hard shoulder as starting point

H11Driver ignoresclosed lane(s)signals that areprotecting an

incident

E08.0 0.0

No Change

More live lane incidents expected with ALR due to theremoval of the hard shoulder. Signalling providesinformation about live lane incidents to motorists

(although monitoring shows poor compliance with RedX at times). Main protection for staff working in live

lanes remain emergency traffic management (see alsoH22)

H82 Short durationstops / debris

removal by TO /maintenance

workers

S07.0 Eliminated This activity is eliminated as it can only now happenwith a rolling road-block. The risk assessment for the

hazard concerning rolling road blocks has beenreviewed and adjusted accordingly.

H94 TO arrives, buthas difficulty

containing thescene

E07.0 -0.1

Hazarddecreased

Mandatory signals and MS4s with pictograms can beused to protect TOs.

H96 TOs behavehazardously at

an incident

E06.5 0.0

No change

Implementation of scheme is not expected to impact onthis hazard.

H34 Incidentmanagement -

rolling block

E06.0 +0.5

Hazardincreased

Expected to be required more frequently (e.g. toremove debris) because hard shoulder is no longer

available with the implementation of ALR

H22 Emergency staff-TO etc on footat scene of an

incident

S06.0 0.0

No change

Expect more live lane breakdowns. Better protection ofeach incident



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Hazard M4 J3 to J12



H101 Unable to setsigns andsignals to

protect incidents

S06.0 0.0

No change

ORR do not rely wholly on signs and signals forprotection

H83 Signals changewhile TO/

emergencyservices are still

on motorway

E06.0 -0.1

Hazarddecreased

CCTV available for operators to check whether there isstill attendance at incident

The highest scoring on road resources (traffic officer) hazards reduce in risk or are eliminated. Therisk from conducting rolling road blocks (H34) is expected to increase as more work is expected to becarried out using a rolling road block.



REV 02 PAGE 33

Maintenance workers

Table 5-4: Most significant and relevant hazards that apply to maintenance workers

Hazard M4 J8 to J12



H52 Maintenanceworkers settingup and taking

down work site

S07.82 - 0.06

Hazarddecreased

Increase in amount of technology and removal ofhard shoulder is compensated by the benefit ofsignalling protecting workers setting out traffic

management, and new techniques formaintenance such as remote fault interrogation,

fixed tapers and secret signs in the verge. Overallrisk expected to be slightly better.

H79 Roadworks - longterm static

S07.5 0.0 The management of long term static roadworks isnot expected to change significantly.

H148(H81)

Roadworks -short term staticon hard shoulder

S07.5 Eliminated This would only be possible intra-junction onjunctions where TJR is not being implemented. In

practice roadworks would not start from suchpositions.

H82 Short durationstops / debris

removal by TO /maintenance

workers

S07.0 Eliminated This activity is eliminated as it can only nowhappen with a rolling road-block. The risk

assessment for the hazard concerning rollingroad blocks has been reviewed and adjusted

accordingly.

H80 Roadworks -short term static

S06.5 + 0.30

Hazardincreased

More equipment needs to be maintained (e.g.signals, MS4s). The controlled environment andthe ability to use signals and signs makes work

safer (this is being developed for HSR andControlled Motorways (CM)). Some activities thathappen under H148 would now happen under this

hazard hence the increase in risk.

H136 Collision withworkers doing

maintenance onverge

S06.5 Eliminated This activity will not be permitted without TM

The highest scoring maintenance worker hazards reduce in risk or are eliminated. The risk of hazard‘H80 Roadworks - short term static’ is expected to increase as more equipment needs to bemaintained. In addition work that was previously carried out on/from the hard shoulder and wastherefore covered by hazard ‘H148 Roadworks - short term static on hard shoulder’ is now coveredunder H80.



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Annex E: Scoring parameters and indices

Figure 5-1: : Hazard scores are calculated as follows:

Calculating risk scores for event and state hazards: Risk scores for both event and state hazards consist of three parameters;

Each parameter is ranked and given a score;

The scores for the three parameters are then added together to give an overall risk score:

o Parameters vary depending on whether the hazard is an event or a state;

o It is not possible to do direct risk comparisons of event and state hazards.

The overall risk can range from:

o Minimum score of E00 / S00;

o Maximum score of E12 / S12.

A difference of 1 in the overall risk scores implies a 10 times difference in risk e.g. an E08hazard has a 10 times higher risk than an E07.

Hazardfrequency

score

Severity ofincidentscore

+Probability of

hazardcausing an

incident score

+ = Total riskscore

Hazardlikelihood

score

Severity ofincidentscore

+Rate at whichhazard stateleads to an

incident score

+ = Total riskscore

Event hazards

State hazards



REV 02 PAGE 35

Table 5-5: Event frequency indices

FrequencyClassification Nominal Value: Occurrences/year/mile Index Value

Very frequent 1000 6.0

316 5.5

Frequent 100 5.0

31.6 4.5

Probable 10 4.0

3.16 3.5

Occasional 1 3.0

0.316 2.5

Remote 0.1 2.0

0.0316 1.5

Improbable 0.01 1.0

0.00316 0.5

Incredible 0.001 0.0

Table 5-6: State frequency indices (likelihood score)

LikelihoodClassification Nominal Value: Occurrences/year/mile Index Value

Very frequent At least 1 occurrence present at any one time perMotorway mile 6.0

Present 115 days per year per Motorway mile 5.5

Frequent Present 36.5 days per year per Motorway mile 5.0

Present 11.5 days per year per Motorway mile 4.5

Probable Present 3.65 days per year per Motorway mile 4.0

Present 1.15 days per year per Motorway mile 3.5

Occasional Present 9 hours per year per Motorway mile 3.0

Present 3 hours per year per motorway mile 2.5

Remote Present 50 minutes per year per motorway mile 2.0



REV 02 PAGE 36

LikelihoodClassification Nominal Value: Occurrences/year/mile Index Value

Present 15 minutes per year per motorway mile 1.5

Improbable Present 5 minutes per year per motorway mile 1.0

Present 90 seconds per year per motorway mile 0.5

Incredible Present 30 seconds per year per motorway mile 0.0

Table 5-7: Collision indices (Rate/probability that hazard lead to an accident)

Probability that an Event/State causes collisions

Classification Events Value States

If this hazard occurs then: This hazard, if present, will:

Certain A collision is certain 4 Definitely causes a collision

Probable A collision is probable 3 Frequently causes a collision

Occasional A collision will occasionally happen 2 Occasionally causes a collision

Remote There is a remote chance of acollision 1

Infrequently causes a collision

Improbable A collision is improbable 0 Rarely causes a collision

Table 5-8: Severity indices (severity of accident score)

Probability that an Event/State causes collisions

Classification Interpretation Value

Severe More fatal collisions than average 2

Higher than average Between average and severe 1.5

Average Collision distribution similar to average motorway 1

Lower than average Between average and minor 0.5

Minor Less fatal collisions than average 0



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Table 5-9: After scoring values

After scoring values

Value % (+/-)

+0.5 216% increase in risk (tripling of risk)

+0.4 150% increase in risk

+0.3 100% increase in risk (doubling of risk)



0.0 No change in risk

-0.1 20% decrease in risk


-0.3 50% decrease in risk (risk halved)





REV 02 PAGE 38

Annex F: Implications of M42 Smart Motorway three yearsafety review

Consideration of the resultsThe first 36 months of validated personal injury accident (PIA) data during 4-Lane VMSL (4L VMSL) isavailable from the M42 HSR scheme [1]. Overall there has been a reduction in the number andseverity of PIAs during the first 36 months of 4L VMSL operations compared to 3L VMSL and No VSL.

On average 2.25 PIAs per month with 4L VMSL compared to 3.17 and 5.08 in the 3L VMSLand No VSL cases respectively.

This represents a 56% reduction between No VSL and 4L VMSL.

PIAs which have occurred during HSR were all slight in severity.

The PIA severity index has fallen to 0.07 with 4L VMSL compared to 0.16 with 3L VMSL andNo VSL.

The number of rear end shunts and single vehicles PIAs per year has dropped significantly with 4LVMSL compared to No VSL, side impacts are unchanged.

The headline PIA figures can be analysed in a number of different ways to represent the reduction insafety risk. This is shown in Table A6-1. This suggests a 60% reduction in safety risk compared to thebaseline is a reasonable representation.

Table 5-10: Analysis of PIA figures - 60% reduction in risk

No VSL 4L VMSL Percentagereduction

PIA rate per month 5.08 2.25 - 56%

PIA rate per month per billionvehicle miles travelled

116 48 - 59%

PIA rate per month * severityratio

0.81 0.18 - 78%

PIA rate per month Weighted 7.5 2.6 - 66%

Note: Weighted: Fatal 10; Severe 3; Slight 1



REV 02 PAGE 39

Implication of M42 HSR benefit for M4 J3-12 SmThe M4 J3-12 Sm scheme needs to be compared with the M42 HSR scheme to see how much of thebenefit it can be expected to achieve. In making this comparison it should be noted that:

The ALR design has significant differences when compared with the M42 HSR design;

A number of operational procedures have been changed since implementation of M42 HSR.

Whilst there are differences between the M42 HSR and ALR concept it is clear that it shares many ofthe components that have contributed to the 60% reduction in safety risk achieved by the M42 andsuggests it may deliver safety benefits.



REV 02 PAGE 40

Annex G: ALR design requirement

Key elements of the ALR design requirement are:

a. The hard shoulder on the main line is permanently converted to a controlled running lane.

b. Variable mandatory speed limits (VMSL).

c. Lane specific signalling only provided at the ‘gateway signals and variable message sign(VMS)’ location and where necessary at intermediate locations.

d. Driver information, including mandatory speed limits, provided at intervals not less than 600mand not exceeding 1500m.

e. Queue protection system.

f. Comprehensive low-light pan-tilt-zoom (PTZ) CCTV coverage.

g. Refuge areas provided at a maximum of 2500m intervals. Refuge areas may either be bespokefacilities (an ERA) or converted from an existing facility, for example a wide load bay, amotorway service area (MSA), the hard shoulder on an exit slip/link road or hard shoulder intra-junction.

h. Emergency roadside telephones (ERTs) provided in dedicated refuge areas (excluding offslips).



REV 02 PAGE 41

Figure 5-2: Illustrative drawing of ALR

annex e hazard log - national infrastructure planning · annex e hazard log. highways agency – m4...

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