Category: Transportation

Universal design and psychosocial disabilities

The COVID 19 pandemic has given rise to new thoughts about planning and design of the built environment including public transportation. People with psychosocial disabilities respond in different ways to situations. Travelling was easier for some because of less crowding, but others feared contamination. Facial masks increased anxiety in some, but others found that people not wearing masks a problem. This is where a universal design approach can help.

” … universal design should include the social and organisation environments, in addition to physical design, in terms of making the transport system accessible to everyone.”

A man stands on a train platform looking at his smartphone. He is wearing a hat and has a bright yellow backpack.

Between 20% and 25% of the population have a mental illness at any given time. People with psychosocial disabilities travel less than others leading to social isolation and worsening symptoms. The World Health Organization (WHO) estimates that by 2030 mental health conditions will be the leading burden of disease.

Improving travel with universal design

Few studies include mental health with reference to universal design. Anja Fleten Nielsen’s study asks “How can a broad understanding of universal design be used to improve travel for people with psychosocial disability?” She investigated the impact of COVID-19 and the main barriers to using public transport.

Nielsen’s study involved in-depth interviews focusing on barriers, travel behaviour during the pandemic and suggested solutions. Recruiting participants was difficult in terms of getting written consent – signing a consent form could raise anxiety levels. Nielsen explains more about methods and the literature review.

The key results are fell into: physical environment, social environment, organisational environment, and individual aspects.

The roadway is marked with the words "bus stop" in yellow lettering.

Physical environment: Crowding, important information during the journey, lack of toilet facilities and sensory overload.

Social environment: Negative experiences with fellow passengers and interaction with transport personnel, and being afraid to ask for help.

Organisational environment: Availability and ease of access, and lack of seamlessness between modes with long waiting times.

Individual level: Planning difficulties, travel induced fatigue and financial barriers.

COVID-19 made barriers more apparent

Nielsen’s paper discusses each of the four aspects in detail. The pandemic increased symptoms in many participants and has made them more visible to transport planners. To answer the question about universal design, Nielsen claims that environmental factors are of greater importance. This is because the individual factors are related to special and customised solutions.

The title of the study is, Universal design for people with psychosocial disabilities – The effect of COVID-19.

Planners and designers need to look beyond physical impairments. Universal design is just as relevant for people with psychosocial disabilities. Social and organisational environments are of equal importance for this group. These are factors that also improve journey experiences for the travelling public.

From the abstract

During and after the pandemic, most informants travelled less and/or used their car more than before. Some stopped using public transport due to fear of contamination, while others found it easier to travel during the pandemic due to less crowding.

Use of facial masks were perceived by some as an additional problem increasing anxiety, while others found it more problematic with fellow passengers not wearing masks. In general, findings support prior studies in terms of barriers related to crowding, lack of seamlessness, financial issues, problems with staff, lack of access in rural areas, and low knowledge of support systems.

Lack of toilet facilities, negative experiences with other passengers, sensory overload, travel-induced fatigue, and problems related to planning are considered problematic. Station areas may pose a barrier for people with former drug addictions. Hence, universal design should include the social and organisation environments, in addition to physical design, in terms of making the transport system accessible to everyone.

New mobility and universal design

On one hand, new mobility technology increases opportunities to improve transport systems. But on the other, the technology is unevenly distributed in terms of access and inclusion. This means many will be left out, especially those with reduced mobility. 

The new technology can create unintended barriers: physical, technological, economic and mental – each one a challenge to universal design. Public policy also has a role to play in reducing barriers to mobility.

Norway has a whole of government universal design policy and has done good work in making public transport accessible. However, many advancements require digital skills in using smartphone apps and electronic ticketing. And that’s just one universal design challenge. 

The challenges to universal design and new mobility are discussed in a book chapter by Jørgen Aarhaug. The chapter title is, Universal Design and Transport Innovations: A Discussion of New Mobility Solutions Through a Universal Design Lens. It’s open access.

From the abstract

Most technological advances in mobility result in better accessibility for many, yet the benefits remain unevenly distributed. New and improved mobility technologies typically result in increased mobility. However, most new technologies create both winners and losers. Who wins and who loses depends on how the mobility solution in question is introduced to the mobility system.

This study finds that many of the new mobility technologies that are introduced, though not directly relating to universal design, strongly affect the universality of access to mobility.

The chapter aims to give insight into how certain new mobility solutions affect different user groups, and to highlight how the outcome is a function of the interplay between technology and its implementation. The paper concludes by pointing to the need for regulation to align the objectives of the actors behind new technologies and an inclusive society.

Automated vehicles: mobility and accessibility

The transportation and mobility sector has a design history focused on infrastructure efficiencies. User perspectives are being introduced in other sectors and it is time for the mobility sector to catch up. 

An article from Norway discusses the issues introducing universal design and co-creation.  The author uses three vignettes to highlight some of the issues users encounter. 

The title of the article is, Automated Vehicles Empowering Mobility of Vulnerable Groups – and the Pathway to Achieve This.

From the abstract

Many people in Europe still have limited access to transportation modes overall. Socio-economic constraints, and cognitive, sensory and physical impairments affect everyday life, posing challenges to accessing mobility services.

Technologies for vehicle automation have advanced in recent decades. Yet, the implementation and use of automated and autonomous vehicles (jointly referred to as AVs) entails chances but also hurdles regarding accessibility and inclusivity of vulnerable groups.

This concerns both the use of the vehicle by humans as well as the interaction between humans and vehicles as participants in road traffic.

In this chapter, we identify opportunities and risks narrow down the vulnerable social groups we are looking at. Subsequently, we present the benefits that co-creation and universal design can have in overcoming or, in the best case, avoiding these obstacles.

Detailed recommendations for action cannot be given within this framework, but suggestions for solutions are outlined.

 

Train station design

The Design Council in the UK has published a full report of the work they did on train station design. The aim of the project was to find a generic train station design that could be rolled out on the various rail networks. For this they undertook some serious community engagement. 

A concept image of the train station design. It's an aerial view showing how the station fits into the existing residential area.

The majority of rail stations are small to medium size situated in the heart of local communities. This is why they have to deliver more than just trains for commuters. 

The community engagement process gave architects design concepts that work as a whole or a kit of parts. This works well when upgrading existing train stations. Key design elements are

The clocktower – acts as a beacon to help identify the station and orientate people.

The welcome mat – extends the public space outside the station. It creates space between people and cars, inviting people to spend time here.

The activity framework – can be adapted to the needs of each place. Provides space for local communities and small enterprises alongside station facilities.

The photovoltaic canopy – even the smallest stations will include a timber framed platform canopy with integrated PV panels.

The pods – create extra shelter under the platform canopy or activity framework. These can include space for passenger facilities such as waiting rooms, toilets or a ticket office. 

Train stations are evolving from a focus on rail infrastructure to a focus on passengers and the local community. This is how you do universal design – with a focus on users.

The full report of the process and the outcomes is documented in Explore Station: Building momentum for a future passenger hub.

 

Universal design and future of transport

What will transport in the future look like, and will it be universally designed? Engineers Australia’s new discussion paper takes a fresh look at transport systems and infrastructure. That means taking a long-term view of the relationship with community, government policy and regulations. A big job with lot of dots to join up. 

Front cover of the future of transport discussion paper. Transport systems are designed to move people and freight, but they need different things. If we are to reduce emissions, we need innovative transport options. That means talking to consumers – passengers, pedestrians, drivers, and riders. It also means revising regulations and digital infrastructure. 

The title of the discussion paper is The future of transport. The section on access for all discusses universal access in terms of people with “mobility challenges”. Reference is made to the the Universal design for transport discussion paper and lists the benefits of accessible transport.

Benefits include better access to employment opportunities and participation, and enhancing quality of life. Getting the design right at the beginning saves money, increases patronage and enhances economic activity. The next section has more information on the earlier universal design for transport paper. 

Engineers Australia welcomes feedback on the latest discussion paper to help inform future work. To provide feedback please email policy@engineersaustralia.org.au 

Front cover of the Universal design for transport discussion paper.Universal design for transport

The paper’s purpose commences with disability statistics followed by reference to disability discrimination legislation and standards. There is a list of benefits and some case studies followed by recommendations. Although the document uses “universal design” in the title, it uses “universal access”. Not quite the same thing. 

Recommendations

The recommendations from Universal design for transport are:

1. Recognise that compliance alone doesn’t mean good accessibility – focus on universal access.
2. Support the DSAPT (Disability Standards for Accessible Public Transport) modernisation process.
3. Leverage existing programs (fleet purchasing, major projects) to get universal access outcomes.
4. Need for long term program and state commitment to retrofitting existing infrastructure to achieve DSAPT standards – including a funding commitment.
5. Make more use of state-based accessibility groups in understanding solutions and prioritisation of finite funding- i.e., maximise accessible benefits.
6. Need to make sure there is access to public transport for those who are reliant on public transport for mobility due to their disability, including in regional areas.
7. Leverage technological advances including internet of things (IOT) and artificial intelligence into wayfinding, access to services etc.
8. Engineers and designers (and regulators) need to have agile mindset to new technologies and ways of providing accessible transport options.
9. Opportunities for new vehicles to be designed for more accessibility- zero emission busses (ZEBs), new trams and trains.
10. Universal access needs to be a guiding principle through the design process not post-design check.
11. Harmonise public transport and active transport infrastructure design standards and best operating practices.
12. Subject matter experts should be engaged at project commencement to identify appropriate standards that lead to good accessibility outcomes.

Universal design should be part of land-use planning, transport planning, and sustainable development, not just equity and inclusion.

The Universal Design for Transport: Transport Australia Society Discussion Paper was published in April 2022

The future of transport discussion paper was published January 2023. To provide feedback please email policy@engineersaustralia.org.au 

 

Shared space on streets and roads

Perceptions of safe walking and cycling routes relate more to visual separation than physical barriers. Bushes provide little, if any, protection for pedestrians and cyclists, but they are sufficient to give a sense of safety. That was a finding in a new report from Germany. So the issues related to shared space on streets and roads is more about the sense of separation not provided by road markings.

Shared space on streets and roads is often contested space. In urban settings, shared space also includes sharing with buildings, street furniture, kiosks, trees and other vegetation.

A cycle-way divided by yellow bollards with a man on an e-scooter and a man on bicycle travelling in opposite directions. Pedestrians are visible on the separated footway.

Many pedestrians avoid shared paths due to the likelihood of cyclists approaching suddenly or silently. It makes them feel unsafe. Cyclists find they need to concentrate more when sharing space with pedestrians. So it seems the shared pathway experiment needs a serious review. What better way than to ask pedestrians and cyclists?

A total of 408 participants took part in a study on this topic. Four options were provided to participants using 3D virtual presentations followed by a survey. The four options for dividing shared space were, bollards, stones, bushes and no treatment. Both pedestrians and cyclists put bushes as their first preference and no treatment as their last preference. Visual separation in the form of lines or road and path marking are considered an insufficient solution.

The study also shows the importance of involving street and road users in design decision processes.

While the researchers challenged the concept of user integration, they do not recommend eliminating the shared space concept. Rather, they propose we re-think the shared space concept for all street and road users, particularly pedestrians who are the most vulnerable.

The title of the article is, Reimagining shared (space) street design: Segregating to better integrate?

Abstract

The shared space concept proposes to reduce traffic control to integrate road users. Yet, defining boundaries to create a pedestrian safe zone is particularly relevant for a successful implementation. Therefore, to determine if road users also expect a protective barrier delimiting the safe zone, this paper presents part of the results of an online survey that evaluated the preferences of pedestrians and cyclists.

A total of 408 participants completed the survey and ranked the alternatives (i.e. none, bollards, bushes, and stones) according to their preferences. Approaches suitable for ranking data were then applied to further understand the results, which indicated that only providing a safe zone with visual separation is not necessarily preferred when compared to the provision of additional physical barriers.

Both pedestrians and cyclists prefer bushes over the presented alternatives. As bushes objectively provide less physical protection than bollards and stones, it can be assumed that the sense of segregation, rather than the physical protection itself, should be considered in shared space design.

By challenging the concept of user integration, this paper suggests reinterpreting the shared space design to combine physical barriers in an attempt to better accommodate vulnerable road users.

Step-free railway stations: benefits for all

If any aspect of a public transit journey creates inconvenience or anxiety, people just won’t make the journey. Or only make when it is essential. This has a knock-on affect for socialisation and the economy. People with reduced mobility usually face more inconveniences than others when using public transport. A study in the UK found that step-free railway stations has benefits for all.

A classic view of a railway station in the UK. Access to the train carriage looks difficult due to the gap between the platform and the carriage door.

A train waits at a railway station platform. In the distance there is a flight of steps to an overpass. The train look modern but the platform looks old.

Lifts to platforms are a good start but this is only one link in the whole journey. The physical aspects are getting to the station, into the station, using a transit card or ticket, and getting onto the platform. Then there’s the matter of getting onto the train, finding a seat, getting off again and ready to negotiate the platform and station at the destination. Lots of actions to seamlessly link up. And then there is the information side of things.

What is step-free?

Researchers in the UK found that transport professionals had different definitions of step-free. Some used guidelines or standards rather than critically thinking about the overall design of the train or station. However, they all interpreted “step-free” as being physical, whereas if it were to be inclusive, it would consider more than steps in and around the station and the train.

Using mixed methods, the researchers found that there was no agreement about what constituted step-free access. In some instances it was confined to the station itself, while in others it included the street to train.

The researchers list the key benefits of inclusive railway design in a table. It tabulates three types of benefit: economic, mental health and physical health. Both direct and indirect revenue and environmental benefits are also included.

Although this paper is focused on UK railway stations and and operators, it makes the links between good accessible, inclusive design and benefits for the economy and society. It goes beyond the traditional benefits for people with reduced mobility, which is what most other studies have done.

Once again, designing for a marginalised group means designing for everyone.

The title of the article is, Step-free railway station access in the UK: the value of inclusive design. The article is part of a collection of papers in a special journal issue, Towards collaborative and more inclusive transport systems. All articles are open access.

From the Abstract

People with reduced mobility travel less than than others. That’s despite substantial investment in step-free access at UK railway stations. This research examines the benefits of step-free access and the wider benefits of railway station accessibility.

The results show that the benefits of step-free access extend beyond those with reduced mobility. It demonstrates the potential to positively affect the society economically, environmentally, and socially.

Government and interested stakeholders should commit to expanding the number and coverage of step-free stations throughout the UK. They should ensure that the appraisal process for investment in step-free accessibility appropriately captures both user and non-user benefits.


Inclusive mobility – a guide

The UK Government has updated their 2002 Inclusive Mobility guide. The update comes from seeking the views of people with disability, representative groups and practitioners. The principles underpinning the guide remain the same in this 2021 document.

The guidance covers features compatible with creating an inclusive environment. Pedestrians include people using all types of mobility aids that are meant for use on footpaths. The guide is focused on people with disability, but many others benefit too. Parents with small children, people carrying or wheeling heavy shopping, people with a leg in plaster, and many older people.

“The research for the guide included the needs of people with mental health conditions, dementia, age-related and non-visible impairments.”

A wet wintery street scene in London showing a line of mid-rise buildings and shops.

The overall aim of the guide is to enable practitioners to create a universally designed public realm, and through that, social inclusion. The document is useful for anyone designing and installing public realm improvements and new infrastructure.

To begin with…

The guide advises practitioners to consider all pedestrians from the outset of the design. This includes any transport or pedestrian infrastructure and planned maintenance. Any conflicts arising between the needs of different disability groups can be resolved by including them in the design process.

“Engagement should continue throughout a project, contribute to the design, and might include user tests and trials.”

People sit around round tables discussing questions. There are four round tables shown in this picture

People with non-visible impairments also find uneven surfaces, crossing the road, navigating slopes and ramps difficult. Hence they are less likely to make the journey. These users benefit from pedestrian environments that are simpler, with distinct features and provision of clear information. Being confident in knowing where you are going is an essential part of feeling welcome in the public domain.

Human Factors

The introduction to the guide covers basic human requirements for ease of movement. This includes generous allocations of circulation space for people using mobility devices, or pushing baby strollers. Taking a universal design approach will generally suit most people. However, some people need specific designs. A deafblind person needs to know when they have the green walk sign and assistive technology comes into play here.

The guide is mainly concerned with people with mobility, vision, hearing, dexterity and reaching, and cognitive conditions. It discusses these in detail so that practitioners can grasp the full range of human diversity.

Footways, pedestrian crossings, changes in level, tactile paving, car parking, bus and tram stops, taxi ranks and transport buildings are all covered. The section on the use of digital transport is important as many information services are either web or kiosk based.

The title of the guide is, Inclusive Mobility: A Guide to Best Practice on Access to Pedestrian and Transport Infrastructure. The guide also reminds practitioners that they have legal obligations to comply with any disability discrimination legislation and related standards.

Future mobility: user views

TRIPS is a European transport project for making new mobility solutions affordable, accessible and safe for everyone. People with disability took part in a study to see what their attitudes were towards future mobility. Bike sharing, e-scooters and motorbike taxies are largely rejected in their current format.

People with disability are open to using smart technology but it needs to be seamlessly integrated for overall levels of transport accessibility. The full results are reported in the White Paper: Views of persons with disabilities on future mobility.

“In a nutshell, our findings suggest that a number an interactive, real-time, accessible journey planner would motivate users to travel and make their journey more independent, faster, easier, nicer, and safer.”

Front cover of the TRIPS White Paper.

553 people with disability from 21 European countries were surveyed for the project. The majority (54%) of respondents had a physical disability, followed by 16% vision, and 8% hearing. 15% of respondents had multiple disabilities.

9 mobility concepts were presented to respondents including ride pooling, micro-transit, motorbike taxi, robotaxi, e-scooter sharing and bike sharing. In general women were less willing to use new mobility systems, particularly ride pooling, motorbike sharing and robotaxis. At this point it is not known why.

Accessibility is a door to door issue. The White paper offers suggestions that include engaging with people with disability in the design of vehicles, services and infrastructure.

A row of e-scooters stand to attention on the footpath.

Design suggestions

Prioritise a journey planner that provides accessible information about door to door journeys. It would improve willingness to travel. Redesign bikesharing schemes, e-scooters and cycle lanes. Ensure AI solutions are developed with people with disability and accessibility experts to avoid bias in design.

A slide presentation by Alexandra Konig has the short version of the White Paper and short term and long term service recommendations. The title is, The views of persons with disabilities on future mobility.

TRIPS = TRansport Innovation for disabled People needs Satisfaction.

Our Streets: Dangerous by Design

The Dangerous by Design report from Smart Growth America has some interesting statistics about road deaths. This 2022 report differs from previous reports because it captures the behaviours of people during a pandemic. People walked more and drove less, but there were more road deaths. The report examines why.

“Seeing driving go down while deaths went up should call into question the long-held belief that traffic fatalities are inextricably linked to the amount of driving.”

Front cover of Dangerous by Design Report.

Conventional wisdom among policymakers and transportation professionals is that traffic fatalities are inextricably linked to the amount of driving. But the decrease in driving during the pandemic meant less congestion and a significant increase in speeds. Therefore more people were killed. Consequently, speed is the key factor.

Smart Growth America claims that too many transportation agencies and decision makers have been “asleep at the switch”. Their incremental changes to improve safety have not made any positive difference overall.

Those in power, “will have to unwind the deeply embedded, invisible yet powerful emphasis on speed, which is completely incompatible with safety.”

Two ambulance officers push a patient into the ambulance.

The Dangerous by Design 2022 report has several recommendations in terms of policy and design. The guest supplements provide practical experience and add depth to the report. The bottom line of the report is that we have to choose between speed and safety.

Walking and wheeling

The report has a sidebar about “walking” and inclusive language. Of course, some people cannot walk and that is why the term “pedestrian” is used throughout. People using mobility devices are considered pedestrians. However, they are not separated from people using other devices such as skateboards. Consequently, data are difficult to assess in terms of people with disability.

An engineer’s perspective

Charles Marohn writes in a guest supplement that engineers start the process by using the values of their profession. They don’t stop to consider their values might be questioned by others. It’s about standard practice. He says no-one asks questions about speed in proposed road and street designs. Engineers might claim they are not in control of how fast people drive, but Marohn questions this “excuse”. He believes they have a duty to consider it.

Measuring transport accessibility

Transport planners are guided by regulations related to mobility, but accessibility requirements relate to what people can achieve.  Accessible transport systems cannot be measured objectively like length or weight but rather by what it enables users to do. So we need a way to merge accessibility measures with infrastructure measures. But how do you measure transport accessibility? Front cover of the discussion paper on measuring transport accessibility. The title is The Accessibility Shift.

Jonathan Levine presents some interesting concepts about accessibility and mobility in his discussion paper. He explores the conceptual barriers to shifting transport planning from mobility to accessibility. Levine also presents a technique for analysing project-level accessibility analysis. 

His thoughts highlight the different goals of accessibility and mobility and how they can be brought together. Transport rules and regulations are the current guiding tools focused on mobility. They are about traffic impact, land use, and transport demands. So embedding accessibility in transport planning requires some new accessibility tools. 

One of the issues with adopting equity principles is that they are usually only seen from a transport disadvantage viewpoint. But everyone benefits when their accessibility increases. Using an accessibility approach enables transport planners to focus on human performance rather than infrastructure performance. 

Ann Arbor is the subject of a case study where Levine analyses the accessibility impact on three land use development projects. This is where the paper becomes technical. 

Levine’s proposed method goes beyond the mobility focus and concepts such as the cost of congestion. The tool takes a standard traffic impact analysis and combines it with an accessibility analysis of an individual land development project. 

The title of the discussion paper is, The Accessibility Shift: Conceptual Obstacles and How to Overcome (one of) Them. 

Accessible public transportation: A book

Front cover of the book showing a typical city street in US. There are cars, buses, a train, bicycles and pedestrians.Everyone is happy when a wheeled mobility user can quickly and easily board the bus or train. And the person wheeling on doesn’t get unwanted attention from other passengers. Based on research in the United States comes a book on accessible public transportation. It covers different technologies, policies and programs with inclusive solutions for everyone. The book is based on research from Center for Inclusive Design and Environmental Access at Buffalo.

The research was carried out with a range of stakeholders and is useful for policymakers, planners and advocates.

The title of the book is Accessible public transportation: designing service for riders with disability . The video below shows what went into the research, and list of chapters following gives an overview of the content. The focus is on people with disability, but of course, designing this group becomes good design for everyone.

1 The Importance of Public Transportation
2 The Culture of Accessible Transportation
3 The Scope of Inclusive Transportation 
4 Trip Planning and Rider Information 
5 The Built Environment 
6 Vehicle Design 
7 Demand Responsive Transportation 
8 Paratransit Scheduling and Routing 
9 Location-Based Information 
10 Social Computing and Service Design 
11 Learning from Riders 
12 Vision for the Future 

Work, transport and wheelchair users

Picture showing the level access from the platform into the train. Work, transport and wheelchair users.

How many jobs can a wheelchair user reach using public transport? Combining wheelchair accessibility with potential jobs is a useful way to show how access is good for individuals and the economy. That’s because we can add anyone with difficulty walking, and also people taking their children to childcare near their workplace. 

Montreal and Toronto are retrofitting their networks to ensure that all individuals can use the public transport system. But will it be enough? A group of transport researchers created a method to identify the public transport barriers that prevent wheelchair users from getting to jobs.

Once the method was devised, they applied it to Montreal and Toronto. They calculated calculate the number of jobs that can be reached within 45 minutes of travel by public transport by a wheelchair user compared to the number of jobs a non wheelchair user can access.

In Toronto, wheelchair users have access to 75% of jobs compared to non wheelchair users. In Montreal this figure drops to 46%. The main reason for the difference is that Montreal has less accessible subway stations than Toronto.

The title of the article is, Comparing accessibility to jobs by public transport for individuals with and without a physical disability. The article covers the development of the methodology, the results and analysis. It is worth noting that if wheelchair users can get out and about easily, others with mobility issues will also be served. So it is not just about a niche group particularly as our population ages.

From the abstract

Not all public transport agencies are currently providing urban residents with comparable levels of service due to physical barriers in the public transport network.

In countries without a strong federal accessibility act and/or with major financial constraints, some public transport agencies fall behind in applying universal access design principles, making it even harder for people with a physical disability to access opportunities.

The objective of this study is to develop a methodology that can be used by
public transport agencies or disability advocates to clearly highlight and quantify the performance of the public transport network in a region. The aim is to compare transit services to wheelchair users and the service offered to an individual not in a wheelchair.

The findings from our study show striking contrasts between the numbers of accessible jobs by public transport for wheelchair users compared to the general population. On average, wheelchair users in Toronto have access to 75% of jobs that are accessible to users that are not in a wheelchair, whilst their counterparts in Montreal have access to only 46% of the jobs accessible to other users.

This research is expected to highlight for public transport engineers, planners, policy makers and advocates for those with disabilities, the importance of universal access in a region, especially along public transport networks, using a widely used land use and transport performance measure.