A Truly Systemic Approach to Road Safety

In many jurisdictions across the world, the approach to road safety is changing from one of managing risk at certain locations, to a broader, more holistic look at trauma crash risk on the road network. This philosophy, known as the Safe System Approach, fundamentally looks to reduce road trauma through anticipating human mistakes and, when a mistake does occur, minimising the severity of impact on the human body. The Safe System approach acknowledges that while people make mistakes, these should not result in death or serious injury. To prevent these outcomes, the focus is on all pillars of the Safe System, including Safe Roads, Safe Speeds, Safe Road Users, Safe Vehicles, and Post-Crash Care.

The Safe System Approach.

Current thinking no longer accepts we should focus on where fatal and serious crashes have occurred. This reactive approach is like strengthening buildings after an earthquake or providing flood protection once a town has flooded. The Safe System Approach, facilitates a better understanding of crash risk across the different parts of the transport system and how best to target this risk

“A system-based approach acknowledges crashes alone are not always sufficient to determine what countermeasures to implement, particularly on low volume local and rural roadways where crash densities are lower, and in many urban areas where there are conflicts between vehicles and vulnerable road users (pedestrians, bicyclists, and motorcyclists).”

Taking a systemic approach to Safe System thinking

Many parts of the world experience unacceptably high fatal and serious crashes. In the USA, individual States are now required to undertake systemwide (systemic) safety risk assessments as part of recent changes to the Highway Safety Improvement Programs (HSIP). In Indonesia, the federal government now requires all transport corridors to have a star rating (iRAP) road safety assessment and meet star rating targets based on road classification. New Zealand is a leader in this area, and we already have a network-wide tool for understanding crash risk, and crucially, for making decisions on how to target this crash risk.

Highway with motorcyclists, Jakarta, Indonesia

Examples of systemic programs include marking and signage upgrades/maintenance, speed management, and better maintenance of road pavements and vulnerable road user infrastructure. Vehicle safety plays a major role, including the early retirement of older unsafe vehicles and encouraging the purchase of smarter and safer new vehicles. An understanding of systemic risk can also help to target high-risk groups, and in doing so address road safety equity issues.

Using tools to target investment

One of the most well-known tools for applying risk rating to roads is iRAP and its various brands (like usRAP). iRAP has been used in over 120 countries and is easy to understand. Road segments are ranked from one star (poor) to three star (good) and to five star (excellent). For many countries, especially low- and middle- income countries, iRAP is the principal method to quantify risk and target investment to address deaths and serious injuries. There are also crash prediction models (safety performance functions), like those in the USA Highways Safety Manual, that apply risk rating to route segments. A major limitation with these tools is their extensive data requirements. They are also primarily used in high-risk areas where significant investment is justified, which means they are not strictly systemic risk assessment approaches due to their limited network coverage. Even if countries were to upgrade all their high-risk corridors, they would still have significant fatal and serious injury crashes.

Star Rating improvement

In New Zealand we have a crash risk assessment process that is truly systemic and covers 90,000km (≈ 55,000miles) of the road network. The process considers nine variables from iRAP that influence crash occurrence and assesses serious crash risk across the network, and systemic treatments to address this risk. This method was also trialed and validated in Australia. It’s main advantage is it uses existing data and does not need additional data collection, which is often a key limitation in many jurisdictions.

New tools deliver network-wide solutions

In summary, reducing fatal and serious trauma on our roads requires a systemic approach to understanding risk across the entire network. In the past, this was challenging and costly due to data limitations. However, with innovative tools like SafeCurves and SafeRoads, we can now deliver truly systemic safety treatments.

SafeCurves, an Abley product, uses a data-driven approach to identify horizontal curves with potential for safety improvements across a whole road network. This enables road safety practitioners to target the areas that need it most, improving outcomes efficiently. This tool is already being adopted by some of our partners in the U.S.

SafeRoads offers a comprehensive way to assess the relative safety of road segments across an entire network. By analyzing roadway geometry, design, land use, and operational characteristics, practitioners can address risks proactively, before they lead to crashes.

Contact us to learn how SafeCurves and SafeRoads can enhance your road safety efforts. Get in touch with Dr. Shane Turner (shane.turner@abley.com) or Steve Abley (steve.abley@abley.com), or visit our website (abley.com) for more details.