Designing for disabilities: a highway engineer's role

Creating and maintaining an accessible public realm is crucial for ensuring that disabled people are not excluded from playing a full role in society.

There are specific things we can do as highways engineers to achieve this.

But it isn’t always straightforward, as we face issues such as retrofitting older infrastructure to modern standards, and what design to choose to meet the needs of differing disabilities.

Why we must design with accessibility in mind

The Equality Act enshrines the rights of disabled people as well as other protected characteristics.

It defines somebody as having a disability if they have a physical or mental impairment which has a substantial and long-term adverse effect on their ability to carry out normal day-to-day activities.

Nearly 18% of the UK population have disability and many people will develop a disability in later life.

The adjustments made for those with disabilities also benefit others with short-term conditions, such as pregnancy, or those with small children.

Therefore, good provision is important to not exclude a significant proportion of the UK population.

It’s a legal requirement

The public sector equality duty, created by the Equality Act 2010, puts a legal requirement on public bodies to address or minimise the disadvantages faced by individuals because of their protected characteristics.

They must implement measures to accommodate the unique requirements of individuals belonging to protected groups, which may differ from those of the general population.

In 2021, the Department for Transport released Inclusive Mobility: A Guide to Best Practice on Access to Pedestrian and Transport Infrastructure.

This guidance sets out the recommendations to provide access to forms of transport.

It ties in guidance from elsewhere, including relevant British Standards, Building Regulations and LTN 1/20 Cycle Infrastructure Design.

The latter is important as a cycle can often be a form of transport for those with disabilities.

The challenge of designing for differing disabilities

There are design considerations which need to be made for the differing types of disabilities.

Some disabled people may have more than one impairment and the requirements of one may disadvantage another.

How do engineers design for mobility impairments?

Mobility impairments includes people who use wheelchairs and those who can walk but only with difficulty.

Those with walking difficulties outnumber wheelchair users by about 10:1.

When designing for those with mobility impairments, some key considerations with regards to transport are level access, sufficient space and rest points.

How do engineers design for visual impairments?

Two million people in the UK have visual impairments, of which around 20% are registered blind or visually impaired.

Use of tactile information assists many to navigate the streets, but use of colour is also important to provide contrast between different items for those with impaired vision.

A good example of a simple adjustment is the provision of flush kerbs at crossing points.

The gradient of kerbs has to be carefully designed to cater for different disabilities. Image credit: Shutterstock

Flush kerbs ensure those in a wheelchair, using a mobility aid, or with a walking difficulty can cross a side road without needing to bump their wheelchair up a kerb, lift their mobility aid, or risk tripping.

Flush kerbs also provide guidance to visually impaired users that they’re at a crossing point.

Guide dogs are trained to stop at flush kerbs so their owner can check for traffic before crossing.

Tactile paving at crossings is formed of raised bumps. This also enables users to detect they are at a crossing through feel and sight using contrasting colours, so they orientate themselves.

Other types of tactile paving are used elsewhere on the transport network to guide visually impaired people and highlight hazards by different types of raised ribs and bumps.

Where it is omitted it can cause visually impaired people to encounter dangerous situations, such as train platforms.

However tactile paving can cause issues for those using mobility aids, as it can make it difficult to push a rollator or wheelchair across tactile paving.

It can also cause discomfort for those with arthritis.

Therefore, it must be used carefully to convey information without excess use.

What do engineers have to consider when designing for hearing impairments?

Around 18% of the UK population has some form of hearing impairment with approximately half over 60.

It's therefore important that key information is conveyed visually as well as audibly.

When navigating the highway network, someone with a hearing impairment might not hear approaching vehicles or cyclists.

They're more likely to feel discomfort sharing spaces with vehicles and cyclists because of this.

Designing for mental health conditions and non-visible impairments

The research undertaken as part of the Inclusive Mobility guidance considered the accessibility needs of individuals with mental health conditions, dementia, age-related impairments, and non-visible impairments.

It identified barriers in the pedestrian environment, such as obstacles, uneven surfaces, road crossings, slopes, and ramps.

It found that these barriers significantly impact individuals with mental health conditions, deterring them from travelling.

Simplifying pedestrian environments, incorporating distinct features, providing clear information, and promoting navigation and confidence in travel would benefit these individuals.

The challenges of retrofitting existing infrastructure to today’s guidance

Within the public realm, we are often retrofitting to existing infrastructure which pre-dates guidance on accessibility.

Often space is constrained geometrically, restricting our ability to provide sufficient width for those with disability to move and turn through the spaces.

Gradients are another challenge, with infrastructure tying into existing topography creating steep gradients not in accordance with the guidance.

Crossing points where the footway ramps down to carriageway level can cause issues.

If the gradient is too steep, a wheelchair or cycle users might struggle to hold themselves stationary waiting for a gap in traffic.

There are also conflicting requirements when redeveloping our infrastructure to prioritise walking, wheeling and cycling.

Changes to the Highway Code in 2022 required that vehicle drivers should give way to pedestrians crossing or waiting to cross a road.

Many authorities are designing side road crossings to give priority to those walking or wheeling through continuous footways, where the footway continues across the side road with give-way marking indicating the need to give way to those crossing.

While this asserts the priority of those walking and wheeling, it removes much of the tactile information those with visual impairment rely on.

This can make the junction invisible to them as they don’t realise they are crossing a road.

How can we check design is inclusive?

There are means to ensure design work is inclusive for all and recommendations have been applied appropriately.

These can be used in all types of engineering projects, not just highway schemes.

Equality Impact Assessments (EQiA) are used to appraise the impact of a proposed scheme on protected characteristics including those with disabilities.

A person independent from the design team can also check that adjustments have been made as far as reasonability practical.

We can consult with user groups to ensure schemes meet their requirements.

For example, we can share a sample of materials to be used on a scheme with a visually impaired group to make sure there’s sufficient tonal contrast.