3 Star or Better

Let’s build a 3-star or better world together!



iRAP believes that improving the world’s roads to a 3-star or better standard is a key way to achieve the United Nations Sustainable Development Goals target of halving road deaths and injuries by 2030.

Raising the standard of the world’s roads to a 3-star or better standard for all road users is helping to focus policy and investment. With crash costs typically halving with each incremental improvement in star rating the potential for 3-star or better roads to save lives is significant.

The global 3-star or better campaign provides decision makers with the knowledge and investment business case to eliminate 1 and 2-star roads and save lives. The independent Fund for Global Health has established the Three Star Coalition to build a group of like-minded organisations advocating for the design and construction of safer roads in the developing world. Specifically they advocate for roads to be built to a minimum 3-star standard for all road users.

Many countries and project managers are now setting targets to increase the percentage of travel on 3-star or better roads and establishing 3, 4 or 5-star standards for new and upgraded roads. The star rating is providing a powerful metric to specify and track road safety performance at the network and project level, just as road authorities set targets for pavement roughness or other asset performance. These objective, evidence-based metrics provide simple, repeatable and realistic targets for countries and organisations to embrace.

Star Rating for all Road Users

Star Rating and Investment Plan inspections create a rich source of data that provides an insight into why road trauma remains one of the world’s leading public health challenges. Based on evidence-based research, Star Ratings for pedestrians, cyclists, motorcyclists and vehicle occupants provide an objective measure of the likelihood of a crash occurring and its severity. 1-star is the least safe and 5-star is the safest.

Star Ratings by road user type based on a 358,000km sample of roads across 54 countries:

Why 3 Star or better?

In a perfect world all roads would be 5-Star (i.e. the safest roads) for all groups of road users.  5-star for pedestrians, 5-star for cyclists; 5-star for motorcyclists and 5-star for vehicle and public transport occupants.  Although there is an overwhelming financial case for investing in safer roads a 5-Star world for all people on all roads will remain as an aspiration for the future.

While high-volume roads can cost-effectively be raised to a 5-star level, 3-Star or better roads for all road users presents a realistic target for national and regional governments and road authorities to adopt.  

Infrastructure upgrades and speed management are the most effective ways to achieve 3-star or better roads for all road users. When investment is not readily available, or is restricted, dramatic improvements can be achieved by a mix of low-cost infrastructure options such as line markings and reductions in speed on the most hazardous sections of the road. 

What is Star Rating?

Star Ratings are based on road inspection data and provide a simple and objective measure of the level of safety which is ‘built-in’ to the road for vehicle occupants, motorcyclists, bicyclists and pedestrians.

Five-star roads are the safest while one-star roads are the least safe.

Broadly speaking, every extra star rating results in a halving of crash cost in terms of the number of people who are killed and seriously injured. Importantly, Star Ratings can be completed worldwide, in urban and rural areas and without reference to detailed crash data, which is often unavailable in low-income and middle-income countries, or is sparse in high-performing high-income countries striving for vision zero outcomes.

Star Rating Guide - what makes a road safe? (Graphic included in the 2018 WHO Global Status Report on Road Safety)

Getting started

Where do you want to go with your 3-star or better target?

View Case Studies from around the world.

Who do you think is most at risk on your roads and where?

The World Health Organisation Global Status Report for Road Safety provides a country by country overview of road safety performance, the scale of death and injury and the road users typically killed or injured. More than half of all road deaths typically happen on less than 10% of roads in a country. Targeting these high-risk road sections with focussed targets for each road user is a great place to start.

Some countries produce regularly updated risk maps which give a valuable overview of the most dangerous roads.  Risk maps provide a visual presentation of the fatality and serious injury risk per kilometre and per kilometre travelled based on historical crash data.

Improving the star rating on these roads where large numbers are killed and injured provides an immediate focus for star rating policy targets and investment to save lives.  In many cases raising high-volume, high-risk roads from 3-star to 4 or 5-star may provide the greatest return on investment. iRAP encourages partners to set targets that ultimately maximise the lives saved within appropriately large budgets - and set minimum 3-star targets for all new projects and road upgrades.

Creating a base-line

A Star Rating analysis assesses the physical condition of road infrastructure and based on evidence-based research a star rating for all road users is produced. The star rating takes into account the specific road attributes that impact safety for the individual road user groups (pedestrians, cyclists, motorcyclists and vehicle occupants).  Identifying the network to be targeted and undertaking a base-line survey is a great place to start. With knowledge of the existing performance of the road network, appropriate targets and investment levels can be explored to ensure an informed and achievable target.

iRAP recommends the highest volume 10% of roads is assessed in each country - noting volumes of each relevant road user group as required (e.g. high-volume pedestrian precincts; cycling or motorcycling routes).


Leading road agencies have experience in setting star rating targets and the common approach now is to set a target for existing roads in terms of the percentage of travel at 3-star or better.  This encourages a sensible focus initially on the higher volume roads for each road user group.

For all new roads, no one can afford for a new one or two star to be built. Minimum 3-star targets are the starting point, and standards should be raised to 4 and 5-star where the investment return is high or ambitions are high.


"X"% of travel on 3-star or better roads by "year" for existing road networks

(e.g. 90% of vehicle travel on 3-star or better roads by 2025; 100% of pedestrian travel on 3-star or better roads by 2030)


4-star or better standard for each road user when volumes are greater than 'X' and

3-star or better standard for all road users on all new road projects

(e.g. 4-star or better for vehicles on all roads carrying 50,000 vehicles or more; 4-star for pedestrians on all roads in commercial districts, around schools or within 1km of a public transport stop)

The UN Secretary General's report (A/370/86 - September 2015) recommends that member states should "improve infrastructure, including by targeting the highest volume 10% of existing roads and set appropriate infrastructure star rating targets for all relevant road users and adopting minimum three-star standards and road safety audits for all new road construction"

Use our 3-star or better resources to support your local leadership or advocacy to adopt a 3-star or better target.

If you need local language versions please let us know and we will help you.



Competitive tendering means that road builders sometimes say they “can’t afford to build safer roads” or that the road is safe as it has been “designed in accordance with the standards”.  New roads are often mistakenly assumed automatically to be safer roads. In fact we know that new roads are still being built to a less than 3-star or better standard effectively locking in high levels of road deaths long into the future.

You can counter this argument with hard statistics that show that 3-star or better roads make sound financial sense. For each star rating improvement crash costs on roads are typically halved.  The road safety 'extras' are often a small (<5%) proportion of the total road project, with returns of investment 5-10 times or more the cost of the additions.

 How do I add a 3-star or better target in my project specification?

It's easy to include a star rating target in your design brief.  The star rating provides a simple, objective, evidence-based and achievable metric for project owners to specify, designers to tender on and road safety auditors or equivalent to verify.  In general we recommend the following template is used for including targets:


The new road shall be designed and constructed to deliver the following minimum smoothed star ratings:


  Pedestrians* Cyclists* Motorcyclists* Vehicle Occupants*
Smoothed Star Rating Target 4 Star or Better 4 Star or Better 3 Star or Better 3.5 Star or Better

*Where road users of that type are present or will be in the future

It's easy to include road safety related Infrastructure KPIs for your network management. See the recommended KPIs for crash data, infrastructure and speed management for existing roads, new roads and upgrades, as well as by road attribute here.

Here are some examples of Star-Ratings related recommendations used around the world:

Star Rating for Design (SR4D) tool

The Star Rating for Designs (SR4D) web app is being developed with the aim of enabling Star Rating to be easily incorporated into the road design process. The app will empower designers to assess the road safety of a design and improve its safety star rating before the road is constructed, thus saving lives and preventing serious injury from the outset.

Find out more information on the tool here

Read about the Launch of the SR4D tool at the Vision Zero and Innovation workshop (Washington DC) here

Star Rate your design

Star rating of designs can be incorporated as part of a road safety audit or completed independently.  The design drawings together with other key project fundamentals such as expected traffic volumes and speed estimates can ensure the star rating of a design can be completed from the desk-top with local knowledge.  Road safety auditors are well placed with the skills needed to star rate designs.

Star Ratings are now being used by many agencies to ensure that safety is built-in to designs for upgrades and new roads prior to construction.

By providing a means of objectively measuring the impact on risk of various design iterations, the Star Rating design process helps to harness the potential of designers to find creative solutions to challenging safety problems.

For governments and development banks, the process opens the opportunity to set performance-based targets for vehicle occupants, motorcyclists, pedestrians and bicyclists that not only improve safety but create a high level of transparency and accountability.

The Star Rating design process has been successfully used in countries such as Australia, New Zealand, Moldova, Qatar and India, in conjunction with existing mechanisms such as Road Safety Audits and highway design standards.

iRAP has developed standard specifications to undertake a Star Rating of a Design that can be included in your project and a trusted network of trained Design Star Rating suppliers around the world is also available.

If you need help iRAP can assist in the direct planning and procurement for a star rating of designs assessment.

Contact: [email protected]

Recommended 6-stage plan for organisations wanting to build SR4D capability

iRAP recommends a 6-stage plan for organisations that want to build SR4D capability.

  1. Join an inception meeting, to meet key iRAP team members and see of how SR4D was developed and how it’s used.
  2. Take the Star Rating Essentials (SRE) online course (5 x 1-hour modules plus assignments). Participants will learn about the iRAP methodology and learn how to use the iRAP software platform, ViDA.
  3. Take the SR4D online course (4 x 1-hour modules plus assignments). Participants learn how to use the SR4D web application to assess designs.
  4. Obtain iRAP interim accreditationby passing the accreditation tests, to join a community of experts that can perform iRAP-specification activities to the same consistently high level of quality worldwide.
  5. Use SR4D in design projects. iRAP key staff offer remote technical support at this stage, including online technical advice and case study workshops.
  6. Obtain full iRAP accreditationby demonstrating successful completion of a project that uses Star Ratings and investment plans. Experts with iRAP accreditation:
  • Are listed on the iRAP website, which is often referred to by organisations such as the World Bank.
  • Agree to a globally consistent Code of Conduct.
  • Have permission to use the iRAP Accredited logo.
  • Get regular updates on the latest developments in iRAP methodology and specifications.

If you would like to know more about SR4D or would like to implement the 6-stage plan in your organisation, please contact [email protected].

Including Star Rating targets in the tender process

Including star-rating targets in the tender process raises the competitive bar among design teams.  The open-ended ‘or better’ target invites designers to aspire to higher performance.  A 4.5 star outcome can be given more weighting than a 3.5 star outcome for a very small percentage of the overall project costs.

Project evaluation criteria can therefore include the safety performance of a road in addition to traditional criteria like cost, time and quality.  The star ratings and associated estimate of life-time crash costs associated with each design can provide an objective, evidence based, global standard that can be used in evaluation criteria.  Refer to our simple tables below as a template for action.

For example tenderers could be ranked by their performance across all of the criteria and/or the costs of road trauma expected in their design could be included in the price evaluation.  For example:

Criteria Tenderer 1 Tenderer 2 Tenderer 3
Safety Performance 2.8 Star 4.1 Star 3.7 Star
Safety Benefit (A) $6 Million $81 Million $65 Million
Cost (B) $112 Million $125 Million $123 Million
Total Cost (B - A) $106 Million $44 Million $58 Million
Ranking 3 1 2

From a whole of government perspective, and for commissioning bodies making a long-term investment in roads and subsequent infrastructure maintenance, there is a powerful argument to pay for better and safer infrastructure at the outset instead of retrofitting at greater cost in coming years.

Safer roads will pay for themselves!

Find out more information by clicking on the icons below.

Measuring outcomes

If the 3-star or better improvements are to be effective and credible the improved roads must deliver the promised results.  Poor comprehension of design elements, lack of appreciation of road safety features by construction teams, rushed deadlines and the use of inferior materials can all compromise standards.

Star Rating the completed project ensures that all the improvements in the design or Safer Roads Investment Plan have been properly completed. It identifies any material changes since the original design was created and possible modifications to the design during construction.  Final payment can be contingent on the achievement of the finished star rating as approved during the design or procurement stage.

Making a difference and saving lives

In February 2016, teams in Slovakia reassessed 327KM of the DI and DZ Motorways and R1 Expressway that had been subject to a €40m improvement package implemented by the Slovak National Motorway Company. The improvements took place following an iRAP Star Rating assessment undertaken in December 2013 as part of the South Eastern Neighbourhood Safe Routes (SENSoRj) project.

Before the upgrade only 27% of the roads had rated 3-star or better for vehicle occupants. The reassessment found that 77% of the improved sections now rated 3-star or better with no 1- star sections anywhere.

It is estimated that over the next 20 years, 355 deaths and serious injuries will be prevented on these stretches of roads.

Make Sure That Improved Roads Stay Safe

Even when a road is confirmed as 3-star or better we can’t afford to relax. Changing patterns in traffic volumes, urban density and urban boundaries and wear and tear/misuse of infrastructure could mean a road will become less safe over time.  It is essential that crash performance on improved roads is regularly monitored.

Regularly updated risk maps can be used to measure and report on the road safety outcomes of investment by governments and funding agencies. Before and after studies also help build the evidence base for future investment and can ultimately be shared in the iRAP Toolkit. If risk maps aren’t available, then a Star Ratings reassessment should be undertaken every 3-5 years to ensure performance is maintained.

Don't let complacency cost lives

Because road environments – and the communities they serve – are constantly in transition, a road’s 3-star rating may be invalidated by changing circumstances.

For instance, in a rural area, an 80km/h or 50mph undivided road with wide centrelines and safe roadsides may deliver a 3-star better road. If the environment served by the road is subsequently urbanised then the safety needs and performance will change.

This common problem is a source of many deaths and injuries. In this scenario, with greatly increased traffic volumes at intersections, the former 3-star or better road will now be 1 or 2 star for all new road users. For the road to be safe, in this new urban environment, it will need to be divided and it will require pedestrian footpaths and safe crossings. The speed limit will also need to be reduced.

All these changes need to be introduced before the new, more dangerous road environment begins to claim lives.

Celebrating Success

Saving lives should be celebrated.  We need to change the public perception around road traffic crashes so they are seen as a major preventable cause of death in the same way as maternal health and insanitary water.

To do this, we need your support. We need you to shout about your successes and build positive publicity around them. Get local MPs, design teams, project owners and road safety practitioners along for ribbon-cutting ceremonies. "Minister opens brand new 4-star road" could become a common headline in regional newspapers and media.  A powerful speech by a key political figure can be inspirational for other road safety advocates. Listen to this speech by Malaysia’s minister of transport, Liow Tiong Lai.

Q: What is the difference between a child’s life saved through vaccination, or as a result of safer roads?

A: None at all!

Yet, while medical campaigns get well deserved publicity for their successes, life-saving road safety interventions struggle to get the same prominence.

When your 3-star or better roads are opened, why not publicise the life-saving benefits of the roads?  Submit your “Share your Life-Saving Success” case study here so we can share it with the world and help to inspire the next project that will save even more lives.

For more information contact [email protected]

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