Passive Safety on Highway Schemes: An Auditor’s Perspective

April 29, 2026

Passive Safety on Highway Schemes: An Auditor’s Perspective

The 40 mph rule: The passive safety requirement threshold for all classifications of roads is 40 mph, not 50 mph, a common misconception in scheme design.
Safe products can combine to create an unsafe system: Passively safe products that perform correctly in isolation may not function as intended when installed in close proximity to each other.
VRS needs clear space, level ground, and the right terminals: Vehicle Restraint Systems (VRS) require sufficient working width, level ground behind the barrier, and correct terminal specification.
Signpost compliance is about more than the post itself: Passively safe signposts should meet specific diameter and wall thickness thresholds, and post spacing should be sufficient to maintain passive safety classification.
A shear-off post can become a projectile: Secondary collision risk, particularly to pedestrians, is a critical but often overlooked consideration when selecting passive safety products.
The DMRB is not the whole picture: Relevant guidance sits primarily within British Standards BS EN 12767:2019+A1:2024 and best practice guidance, the principles of which are applied in the Design Manual for Roads and Bridges (DMRB).

Introduction

Passive safety is a fundamental consideration in the design and assessment of modern highway schemes. The principle is straightforward: in the event of an errant vehicle leaving the carriageway, the roadside environment should be designed to minimise the severity of the resulting collision. Passively safe products, from signposts and lamp columns to vehicle restraint systems, are engineered to absorb or redirect impact energy in a controlled way, rather than behaving as rigid, unyielding obstacles.

But specifying a passively safe product is only part of the picture. How that product is installed, what surrounds it, and how it interacts with the wider highway environment are equally important. These are the issues that our road safety auditors are trained to identify.

The Interaction Problem: When Two Safe Products Become One Unsafe System

One of the most important and frequently overlooked considerations in passive safety auditing is the interaction between individual products. A product may be certified as passively safe in its own right, but when installed in close proximity to another passively safe feature, the combined effect may not perform as intended by the manufacturer.

A common example is an Armco barrier with a general signpost located directly in front of it. Both products may meet passive safety requirements independently, but if a vehicle strikes the post, the presence of the barrier directly behind it could prevent the post from deforming and dissipating energy as it was designed to. The result could be a more severe outcome than if either product had been installed in isolation.

Narrow footpath alongside a dual carriageway with metal Armco barrier, road signs directing to Taunton, Exeter and South Molton via the M5, with overgrown verge and trees in the background

Vehicle Restraint Systems: Working Width, Terminations and Tie-Ins

Vehicle Restraint Systems (VRS), including safety barriers and parapets, require particular attention during a road safety audit. There are three specific areas auditors focus on:

1. Working Width
Every VRS has a defined working width: the lateral distance the barrier deflects upon impact. This space should be clear of obstructions, and the ground behind the barrier should be reasonably level. If the verge slopes away behind the barrier, a vehicle could become wedged beneath it or roll down the slope, significantly worsening the outcome. Working width requirements are generally determined by speed limit: higher-speed roads require greater working width, and auditors should verify that the installed product is appropriate for the prevailing speed environment.

2. Termination Points
The end terminals of a VRS run are a critical safety feature. An incorrectly specified terminal can act as a ramp, launching a vehicle upward on impact rather than absorbing the energy or cause vehicle spearing. Auditors look for appropriate terminal types, such as the P4 terminal, which is designed to compress on impact and prevent vehicle override. This is a detail that can easily be missed on a design review, but is clearly visible and verifiable on site.

3. Tie-In Points
Where a new VRS run connects to existing infrastructure, such as a bridge parapet, the transition should be carefully designed. Moving from a flexible, energy-absorbing barrier to a rigid structure creates the risk of ‘pocketing’, where a vehicle becomes trapped in the barrier during impact, causing sudden and severe deceleration. Auditors verify that tie-in terminals are present and correctly specified to ensure this transition is managed safely.

Passively Safe Signposts: Specification and Spacing

Passively safe signposts are defined by a combination of post diameter, wall thickness, and spacing, all of which should fall within specified limits for the structure to retain its passive safety classification. The relevant British Standard sets out maximum post sizes. For example, a 76 mm diameter steel post of a certain wall thickness may be classified as passively safe. In comparison, a larger 88 mm-diameter post may require a thinner wall thickness to achieve the same classification.

Critically, it is not sufficient to use a compliant post. The spacing between posts also matters. If posts are installed too closely together, the structure may no longer behave as a passively safe system, even if each post meets the specification.

Roadside construction area beside a busy road showing disturbed ground and Armco safety barrier, with a green directional sign for The Strand Coach Drop Off and a DHL lorry visible in traffic

Newly constructed road descending a steep gradient with timber post-and-rail fencing on both sides, 10% gradient warning signs, and a panoramic view of a Welsh valley town with a stone viaduct and wooded hillside beyond

Secondary Collisions: Protecting Vulnerable Road Users

A passively safe product is not always the right product for every location. One of the more nuanced judgements auditors should make is whether a low-energy-absorbing product, one that shears off completely on impact, is appropriate given its surroundings.

In a footway or pedestrianised area, a shear-off product might successfully prevent a vehicle from continuing on its errant path, but the severed post could be projected into pedestrians nearby. In such locations, a high-energy-absorbing or high-containment product is preferable: one that wraps around the vehicle and decelerates it progressively, rather than shedding components that could become secondary projectiles.

Similarly, where a shear-off product is used in a verge location, auditors consider whether there is sufficient clear space for the post to deflect and come to rest without rebounding into the carriageway. A controlled failure into open ground is very different from one constrained by a wall, fence, or embankment.

Standards and Guidance: What Applies and Where to Find It

Designers sometimes assume that passive safety requirements are set out clearly in the Design Manual for Roads and Bridges (DMRB). In practice, the DMRB contains limited specific guidance on passive safety. The primary reference is the relevant British Standard, which sets out post specifications, classification thresholds, and requirements for different road types.

One area where practitioners can be caught out is the speed threshold at which passive safety becomes a requirement. On all classification roads, the relevant threshold is 40 mph, not 50 mph, as is sometimes assumed. This distinction can have significant implications for scheme design and is the kind of detail that auditors are well-placed to highlight.

Beyond the British Standard, much of the practical guidance on passive safety is found in professional best practice rather than in formal regulatory frameworks. This makes it all the more important that auditors bring experience to the assessment, rather than relying solely on checklist compliance.

Auditing passive safety elements of scheme design requires auditors to think systematically. Considering how products interact, how they perform in their specific installed context, and what the consequences of failure might be for all road users, including the most vulnerable.

The issues outlined here, product interaction, VRS working width and termination, post specification and spacing, secondary collision risk, and the correct application of standards are recurring themes in passive safety audits across a wide range of scheme types. Early intervention at the design stage is far preferable to identifying problems during a Stage 3 audit or, worse, following a collision.

If your scheme includes passive safety elements, early audit input can prevent costly redesign at Stage 3. Get in touch.

TMS Consultancy provides independent Road Safety Audits at all stages — from preliminary design to post-construction. Our auditors bring extensive experience across a wide range of scheme types, including complex passive safety assessments.

Get in touch at info@tmsconsultancy.co.uk or request a quote below.

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Road Safety Audits

Ensuring Accessible EV Charging

February 25, 2026

Ensuring Accessible EV Charging: The Role of Design Guidance, PAS 1899 and Road Safety Audits

With the ever-growing number of EV sales and their use on UK roads, the charging infrastructure supporting them has also grown. At TMS, we have conducted Road Safety Audits at several charging locations, generally in busy urban areas.

In this article, our director, Richard Cook, takes us through the guidance and standard which is in place to ensure that the charging infrastructure is accessible for disabled drivers.

Why Accessibility in EV Charging Matters

EV chargers can be located in various environments; they are most commonly found in car parks, petrol station forecourts, and busy urban areas, often utilising existing on-street parking spaces.

However, not all of the chargers are accessible to disabled drivers. One in five people in the UK lives with a disability. By 2035, there is expected to be around 2.7 million disabled drivers, with up to 50% of these being fully or partially reliant on the public charging network.

The Motability Foundation, the charitable organisation that oversees the Motability Scheme, identified a lack of accessibility across the UK’s electric vehicle (EV) charging infrastructure. They have partnered with the charity Designability, which has developed design guidance for manufacturers, installers, providers, and site owners of public electric vehicle (EV) charge point infrastructure to ensure accessibility for all users.

This guidance was informed by engagement with over 200 Motability Scheme members, ensuring it considers the lived experience of the public charging network.

The guidance is to support the BSI standard for accessible EV Charging, PAS 1899:2022,

The design guidance is split into three sections:

Signage and Information
Built Environment
Charging an Electric Vehicle

Signage and Information Guidance

Precise and reliable information is essential when planning a journey. Access to up-to-date information about the charging network is a key part of planning a journey with an EV. For disabled users, this is particularly important; uncertainty about accessibility can be a significant barrier to accessing the public charging network.

The design guidance emphasises the provision of accurate information about charging points. This should not be limited to just the charging speed, connector type, cost and availability, which are currently widely used. But also accessibility-specific information, such as parking space size, space around the vehicle, charger position, level access, and any nearby amenities.

Onsite signage is also key and should clearly display where the chargers are located, any charging restrictions, time limits, and more. The signage should be placed where it does not create an obstruction and ideally in a place where it is readable from both seated and standing positions, without the need to leave the vehicle.

Disabled man charging an electric car with an EV charger.

The Charging Process and Usability

The charging process itself must be usable by people with disabilities and account for a wide range of disabilities, including physical, sensory, and cognitive.

All parts of the charging unit, including screens, buttons, payment, and cables, should be visible and reachable from both standing and seated positions. The units should also be designed with visually impaired users in mind, ensuring clear labelling, good contrast, and appropriate screen height/tilt.

The guidance states that reaching a component does not guarantee it can be used, and that minimising strength, grip, and dexterity requirements helps ensure the unit is accessible. Design solutions should aim to reduce unnecessary cable weight and allow connectors to be held and operated in multiple ways, including one-handed use.

The steps needed to start, stop and pay for charging should be as few as possible. Systems should not rely on smartphone apps alone and should provide alternative ways to pay, such as contactless payment. Users should also be given enough time to complete each step without the unit ‘timing out’. Visual, audible and written cues should also be provided throughout the charging process.

The Role of Road Safety Audits in EV Charging Infrastructure

The Road Safety Audit generally limits us to only assessing any problems that could result in injuries. We may find issues such as trailing charging leads becoming a trip hazard, level access to the vehicle for mobility impaired users or improper placement of the charger itself which could result in collisions.

Although generally Road Safety Audits are only carried out on the public highway, it is important to note that these issues remain the same even when installed on private property, such as car parks.

We have seen an increase in the need for Road Safety Audits on EV chargers over the past few years. This can only be a good thing as improper installation of chargers could result in injuries to both pedestrians and potentially vehicle occupants.

Disabled woman taking out the charger plug from an EV charger.

Conclusion

As electric vehicles become increasingly mainstream, ensuring the charging infrastructure is accessible to all users is essential and the industry should prioritise inclusive design from the outset.

Matt Ford, Designability’s Director of Design & Innovation, sums up the guidance by saying:

“As EV charging infrastructure expands, accessibility and safety must go hand in hand. Our guidance, informed by the lived experience of disabled drivers, supports PAS 1899 and goes beyond compliance to help the road safety industry design and assess EV chargers that are not only safe, but genuinely usable for everyone.”

Richard Cook, Director at TMS Consultancy, has this to say on the guidance:

“At TMS, we recognise that conducting a Road Safety Audit of an EV charger is only one part of creating accessible infrastructure. While our audits focus on safety and injury prevention, the wider design considerations outlined in this guidance are equally important for creating a charging network that works for all users.”

If you would like more information on the accessibility guidance, contact details for Designability can be found on their website.

Why Commission a Road Safety Audit for EV Charging Infrastructure?

Independent Road Safety Audits
Compliance with DMRB GG 119
Identification of injury risk to pedestrians and vulnerable users
Experience auditing urban, forecourt and on-street charging environments
Practical, cost-effective mitigation recommendations

If you are planning or installing EV charging infrastructure on the public highway or within a development, our team can provide independent Road Safety Audit services aligned with national standards.

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Do EV charging points require a Road Safety Audit?

It depends on where the charging point will be located, if it is located in an area which may be a potential hazard to pedestrians or vehicles then a Road Safety Audit may be required. If you are unsure, it is best to check with the Local Highway Authority and they will be able to inform you.

Are EV chargers on private land subject to Road Safety Audit?

Although it may not be essential to get a Road Safety Audit on an EV charger on private land, it can be a good idea. A Road Safety Audit will help you ensure that where you plan to locate the unit is safe and will not pose a risk of injury to pedestrians or vehicles. Within a Road Safety Audit Report we would make recommendations to reduce the risk of any potential injury to risk to pedestrians or vehicle occupants.

What stage of design should EV chargers be audited?

A Road Safety Audit would generally be carried out at either preliminary design or detailed design stage, an RSA Stage 1 or combined 1&2. An Road Safety Audit may also be carried out post construction, or what is known as a Stage 3 Road Safety Audits.

What are common safety issues with EV charge points?

Some common safety issues we may find include; trailing charging leads becoming a trip hazard, level access to the vehicle for mobility impaired users or improper placement of the charger itself which could result in collisions.

Road Safety Audits

Road Safety Strategy – A Professional Perspective from TMS

February 19, 2026

Road Safety Strategy – A Professional Perspective from TMS

The Department for Transport’s Road Safety Strategy, published in January 2026, sets out a new long-term approach to reducing deaths and serious injuries on Britain’s roads.
There is the introduction of targets to cut the KSI rate by 65% for 16+ and by 70% for children under 16.
The plan to set up both a Road Safety Investigation branch and a Road Safety Board.
Signifies a stronger move towards a Safe System approach, it focuses on safer road design, improved vehicle safety, stronger enforcement and targeted education, alongside proposals aimed at protecting vulnerable road users and addressing high-risk behaviours.
Together, the measures are intended to deliver a sustained and significant improvement in road safety over the coming years.

Following the recent release of the DfT’s Road Safety Strategy, we invited Phil Cook, Director of TMS Consultancy, and Steve Proctor, Honorary Associate of TMS – both highly experienced road safety professionals, to share their views on the document. Their thoughts and perspectives are shared below.

Perspective from Phil Cook – Director, TMS Consultancy

The publication of the DfT’s Road Safety Strategy in January 2026 is a welcome and positive step, with the potential to significantly reduce the number of people needlessly killed or injured on our roads. Having worked in road safety for more than 40 years, it’s genuinely encouraging to see a renewed national focus in this area. TMS has long been an advocate of the principle of ‘Safer Roads for Everyone’, supported by clear casualty-reduction targets, and the last time we had a national strategy with firm targets in place, it delivered real success.

The introduction of targets to cut the number of people killed or seriously injured by 65%, and child casualties (under 16) by 70% by 2035, against a 2022–2024 baseline, marks both an exciting and demanding period for road safety. Achieving these reductions will require a strong commitment to new and enhanced measures – supporting safer behaviour by road users, delivering safer road environments, making better use of new technologies, strengthening legislation to tackle poor road user behaviour, and ensuring enforcement is properly prioritised and resourced.

Car crash with Police car in the background.

While the individual measures set out in the strategy are positive, it’s not yet clear whether they will be sufficient on their own to meet such ambitious targets. Progress will need to be closely monitored, with a willingness to introduce further action where needed. Advances in vehicle technology and better data will undoubtedly help, but long-term funding and sustained political commitment will be crucial.

Of course, financial pressures and shifting priorities can complicate delivery, and some necessary legislative changes may prove unpopular – even when they are clearly in the wider public interest. As the saying goes in investment, ‘past performance doesn’t guarantee future results’, and the same can be true in road safety. That said, having ambitious targets once again linked to a national road safety strategy is a major step forward and a genuine reason for optimism.

Phil Cook – BSc, CEng, MICE, MCIHT, FIHE, NH RSA Cert Comp (Director)

Perspective from Steve Proctor – Honorary Associate, TMS Consultancy

The Road Safety Strategy marks a key milestone in the road safety industry and is long overdue. It has been a long time since we have had any targets related to road safety, so this is a welcome and positive change.

The inclusion of Safety Performance Indicators (SPIs) is helpful, although reliance on Stats-19 contributory factors may not be as robust as some would hope. Only one SPI—relating to vulnerable road users (VRUs) is rate-based, meaning that most indicators do not account for exposure. The VRU SPI is based on distance travelled, so caution will be needed when making comparisons with motor vehicle rates.

There are several other positive initiatives, including the proposal to establish a Road Safety Investigation Branch and efforts to better link police and health service collision data. This linkage could be particularly valuable if MAS3+ (life-changing injury) health data can be used to track progress against the targets. The creation of a Road Safety Board, supported by an Expert Advisory Panel, is also encouraging, although its effectiveness will be judged on how it can play an active role in monitoring progress and improving SPIs.

The formal shift in terminology from “accident” to “collision” is noted and welcome. However, there is no reference to legislative change to require collisions to be reported to the police, meaning under-reporting is likely to remain an issue.

The strategy refers to forthcoming legislation on new forms of transport, including e-scooters, and the expansion of existing trials. However, there is no mention of throttle-powered e-bikes or the potential dangers associated with their illegal use.

The role of the Safe System approach within the document is interesting. It appears to be positioned more as a high-level vision or framework for government leadership and local flexibility, rather than using the Safe System pillars as the foundation for specific, deliverable actions, as has been the case in some previous national and local strategies.

Many of the newer and potentially more radical measures are subject to consultation. This raises the possibility that proposals relating to learner, young and older drivers, and to drink- and drug-driving limits, may ultimately be diluted, despite the evidence presented within the Strategy.

Finally, Theme 3 – Infrastructure, is the shortest section of the document and arguably the most disappointing. There is no reference to Road Safety Audit or collision investigation, and iRAP is mentioned only briefly in relation to the Strategic Road Network. While the long-awaited Manual for Streets 3 is acknowledged, no publication date is provided. The section on Smart Motorways is ambiguous, stating that evidence suggests they are safer than conventional motorways, while confirming that no further schemes will be built due to public concern.

Overall, the strategy is clearly written and appears more coherent and better integrated than previous road safety strategies. The reintroduction of casualty reduction targets, which are long overdue, is particularly welcome and the level of ambition is clear. However, meeting these targets will require action.

Steve Proctor – MSc, MCIHT, MCILT, FSoRSA, NH RSA Cert Comp (Honorary Associate)

In summary, the Road Safety Strategy sets out ambitious targets and a clear framework for reducing road casualties. While challenges remain in delivering the full impact of its measures, having a national strategy with defined goals is a major step forward. With careful monitoring, ongoing innovation, and sustained commitment, there is genuine reason to be optimistic about making Britain’s roads safer for everyone.

Road Safety Audits

Delivering Road Safety Audits for the A361 North Devon Link Road

February 2, 2026

Delivering Road Safety Audits for the A361 North Devon Link Road

TMS Consultancy has been involved in the A361 North Devon Link Road highway improvement scheme since June 2023, delivering both Stage 2 Detailed Design Road Safety Audits and Stage 3 Post-Construction Road Safety Audits.

North Devon Link Road, Bridge and Roundabout.

Introduction

The A361 North Devon Link Road connects North Devon and North Cornwall to the M5 motorway and the rest of the UK, acting as a crucial economic lifeline. Key objectives of the project include enhancing road safety, increasing traffic capacity, supporting regional economic growth and improving journey time reliability. The scheme focused on upgrading a 10-mile section of the route between South Molton and Barnstaple.
The works included the construction of new 2+1 wide single carriageway sections, a new grade-separated junction, two new roundabouts, improvements to existing priority junctions, and the creation of new pedestrian and cycle routes.

During the phased design and construction periods, TMS carried out over 20 Road Safety Audits. Our engineers undertook detailed inspections and assessments covering a wide range of safety-critical elements, some of which are highlighted below.

Safety-Critical Elements

Roadside features such as embankments, cutting slopes, drainage ditches and headwalls, to reduce the risk of vehicle rollover incidents. Rigid and heavy-duty items within verges, including signposts, lighting columns, trees, dense vegetation and telecommunications equipment, to minimise the risk of high-severity impact injuries.

Road Restraint Systems, ensuring they were correctly specified, located and installed to safely contain vehicles and redirect them away from roadside hazards.

Boundary fencing design, to reduce the risk of “spearing-type” injuries.

Signs, road markings and reflective studs, to ensure they were clearly visible, legible and correctly positioned to support safe driver navigation.

Street lighting provision, with particular focus on achieving appropriate uniformity at conflict points such as junctions and pedestrian crossing locations.

Skid resistance of the road surface, especially on approaches to bends, junctions and other higher-risk areas.

Visibility splays and stopping sight distances, ensuring compliance with design standards and suitability for the operating environment.

Pedestrian and cycle routes, reviewing surfacing, signing and lining to ensure safe and intuitive use.

Road Safety Audit on the Devon Link Road

What Our Road Safety Auditors Said

TMS engineers involved in the project, Hammy Aulak, Richard Marriott and Mike Fuller, commented:

“We were delighted to be involved in this significant infrastructure project. Our role allowed us to apply our expertise to help deliver a safer road for all users, while also enabling us to build on our knowledge of emerging technologies and best practice associated with large-scale highway schemes.”

A few more Road Safety Audits are planned to complete outstanding remedial works on certain project elements, with completion expected in early 2026.

Conclusion

Road Safety Audits remain a critical component of the highway design and delivery process, ensuring that schemes are safe, compliant and fit for purpose before opening to traffic. As demonstrated through this project, a structured audit undertaken in line with GG 119 enables potential safety risks to be identified early, supporting informed decision-making and helping designers, developers and highway authorities meet their statutory obligations.

For housebuilders, civil engineering consultancies and transport planners, engaging an experienced audit team adds value beyond compliance alone. Independent review, clear recommendations and a collaborative approach help reduce risk, minimise costly design changes later in the programme and contribute to safer outcomes for all road users.

If you would like to understand how a Road Safety Audit could support your scheme — whether at feasibility, detailed design or post-construction stage

Do you need a Road Safety Audit for your highway scheme? Whether local or nationwide, please call us on +44 (0)24 7669 0900 or please email Lorna Styring . Alternatively, you can request a quote using the link below.

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What is a Road Safety Audit?

A Road Safety Audit is a systematic process for checking the road safety implications of highway improvements and new road schemes. The objective of the process is to minimise future road collision occurrence and severity once the scheme has been built and the road comes into use.

The audit takes into account all road users, particularly vulnerable users such as pedestrians and pedal cyclists. Having identified potential road safety problems, the audit then makes practical recommendations for improvement.

With these safety objectives in mind, the auditors need to ask the question “Who can be hurt here, and in what way?”

Why is auditor independence important in a Road Safety Audit?

Independence ensures the audit is objective and free from design bias, providing unbiased safety recommendations that highway authorities and developers can trust. Independent audit teams are a key requirement in GG 119, find out how we ensure our audit teams independence at TMS.

What happens after a Road Safety Audit is completed?

Following the audit, the design team prepares a formal response, often called a Designers Response, to each recommendation, outlining how issues will be addressed or providing justification where recommendations are not accepted. This audit response process ensures transparency and accountability.

Road Safety Audits