A car driving down an unsealed road in rural Australia.
Empowering Transport Excellence

Best Practice Guides

NTRO's Best Practice Guides are essential resources designed to enhance the management and maintenance of road and bridge assets. Building upon our extensive research over 60+ years when NTRO was known as ARRB – the Australian Road Research Board - these guides offer practical advice to local government authorities, state and territory road agencies, and industry practitioners, promoting consistent and effective practices across Australia.

Why NTRO's Best Practice Guides Matter

These guides serve as invaluable tools for improving the quality and longevity of Australia's road infrastructure. By adhering to the best practices outlined, practitioners can ensure safer, more durable, and cost-effective road networks, ultimately benefiting the communities they serve.

A mock-up of NTRO's four Best Practice Guides.
Birds eye view of a local Australian suburb.
A person reaching for a book on a library shelf.
Photo of Sydney Harbour
Photo of Sydney Harbour

Best Practice Documents

NT-G01.00-01:2025
Best Practice Guide
The Evaluation of Marginal and Non-standard Materials in Road Construction
This Best Practice Guide provides a structured approach for the evaluation of marginal and non-standard materials in road construction through large-scale laboratory testing. It is intended for situations where materials fall outside conventional specification frameworks and where small-scale laboratory tests are insufficient to reflect field performance due to scale-related limitations (e.g. edge effects and unrealistic confinement).
NT-G04.00-01:2025
Best Practice Guide
How to Evaluate Unsealed Roads Based on Current Condition
This Best Practice Guide defines a consistent approach for collecting and analysing condition data for unsealed roads. It is intended to capture a reliable snapshot of asset condition in terms of safety and serviceability at a specific point in time, supporting technical assessments and informed decision-making. While various methods are currently used, this Best Practice Guide addresses the need for a unified methodology tailored specifically to unsealed road networks, promoting improved accuracy, efficiency and comparability across jurisdictions.
NT-R01.00-01:2025
Best Practice Reference
Determination of the Embodied Carbon for Pavement Structures
This Best Practice Reference has been developed to provide a harmonised framework and consistent method for the measurement, reporting and interpretation of embodied carbon across the life cycle of pavements. It is focussed on roads but is also applicable to airport and port pavements. It is intended to support practitioners, asset owners, policymakers and industry stakeholders in making informed decisions that align with Australia’s sustainability goals and international climate commitments.
NT-R01.04-01:2025
Best Practice Reference
On-Site Assessment of Sprayed Seal Binder Oxidation
This Best Practice Reference specifies a procedure for the on-site assessment of bituminous binder condition in sprayed seals. It includes the use of Fourier-transform infrared spectroscopy (FTIR) and provides guidelines for evaluating the extent of binder oxidation.
NT-R03.00-01:2025
Best Practice Reference
The Cost Impact of Additional Loading on Existing Sealed Road Pavements
This Best Practice Reference addresses the cost impact of additional loading on pavement assets. It provides practitioners and authorities responsible for managing road assets with a standard framework and guidelines for the assessment, analysis and quantification of the impact of additional traffic loading on existing sealed road pavements. Additional loading of a specific route or road section(s) refers to when heavy vehicles are allowed to undertake a freight task greater that the normal (or base) loading, such that it has the potential to significantly accelerate pavement wear, Additional loading can shorten the lifespan of road pavements and surfacings, especially on pavements not designed for them. Flexible pavements, such as sealed granular pavements which are common in rural/low-volume roads, are especially vulnerable.
NT-R03.00-02:2025
Best Practice Reference
Assessment of the Vulnerability of Road Pavements (Pavement Vulnerability Index)
The purpose of the pavement vulnerability index (PVI) is to reflect the vulnerability of a given length of road pavement if subjected to a flooding event. The index reflects the potential vulnerability of a pavement based on its current conditions and composition. The index does not consider the likelihood of a flooding event occurring. In general terms, the calculation of the PVI considers the damage caused to a road pavement due to flooding and the speed of flooding waters, and the additional consequence of traffic loading of the pavement while the pavement is in a saturated state. The PVI is intended for use in road network management. The index calculation is based on pavement engineering judgement.
NT-TM01.04-01:2025
Best Practice Method
On-site Assessment of Sprayed Seal Binder Oxidation Procedure
This test method sets out a procedure for the rapid on-site measurement of bituminous binder oxidation using a portable Fourier Transform Infrared spectroscopy (FTIR) device. The FTIR spectrum can be used on-site to measure an oxidation peak to assess how oxidised a bituminous binder is. The scope of this test method includes FTIR testing of sprayed seal binder samples that have been collected either from an aggregate particle removed from the sprayed seal or were removed directly from between aggregate particles within the sprayed seal.

Guides to enhance quality and longevity of Australia's road infrastructure

Materials Guide

The Best Practice Guide for Road Materials provides local government authorities, state and territory road agencies and other agencies responsible for the management of sealed and unsealed roads with guidelines on ways to manage their road materials, and to achieve both a sustainable and cost-effective outcome.

The Guide provides a strong focus on the understanding and management of road materials and addresses the main topics of materials in relation to pavement design, construction, management and operation.

Unsealed Guide

The Best Practice Guide for Unsealed Roads provides local roads practitioners with a practical guide for the better basic understanding and management of unsealed roads. This is achieved by consolidating in one document best practice knowledge of the latest methods in asset management, pavement design procedures, construction and network operations for unsealed roads in Australia.

Sealed Guide

The Best Practice Guide for Sealed Roads provides local roads practitioners with a practical resource for the better basic understanding and management of sealed local road pavements. This is achieved by consolidating in one document background knowledge of the latest methods in pavement design procedures, developments in road surfacing technology and road building practices for sealed local roads in urban, rural and remote areas around Australia.

The Guide provides a strong focus on pavement management requirements relating to sealed local roads, and addresses the main topics of design, construction, maintenance and rehabilitation.

Bridge Management Guide

The Best Practice Guide for Bridge Management provides an overview of the basics of Bridge Management including; management, decision making, governance, risk frameworks and legal considerations; operations and maintenance; procurement of relevant services related to bridge management and asset disposal, re-purposing or replacement
This guide provides references that assist with the various processes associated with managing assets and templates and proformas for the more common tasks such as procurement of specific services.

Purchasing Hard Copies

For those who prefer physical copies, NTRO offers the option to purchase professionally printed versions of the Best Practice Guides.

Order Hard Copies

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