Road safety is a global issue, as each year more than 1.25 million people die in traffic accidents, and between 20 and 50 million suffer non-fatal injuries. Road Safety Audits (RSA) are implemented in different countries around the world. These audits involve a systematic process that includes an analysis to ensure that existing or future roads meet optimal safety criteria. In this context, the objective of this research is to identify the main guidelines applied in RSA through a literature review conducted using the PRISMA-ScR methodology. After grouping the guidelines, the ten most used worldwide are obtained, with four of them related to the human factor and six related to the road factor. The guidelines with the highest usage are those related to geometric design, signage, and safety devices. Finally, it is concluded that despite road accidents being an international issue faced by all countries, there is no clear or standardized methodology for the application of these audits. In other words, each country adopts its own method or checklist as a support tool for the team of auditors conducting RSA.

Historically, traditional transportation planning has promoted public policies focused on building and maintaining infrastructure for private cars to improve travel efficiency. This approach presents a significant challenge for cities in the Global South due to their unique socioeconomic conditions and urban development patterns. Dedicated public transport infrastructure can make better use of the road network by moving more people and reducing congestion. Beyond its environmental benefits, it also provides the population with greater accessibility, creating new development opportunities. This study uses Mexicali, Mexico, a medium-sized city with dispersed urban growth and a high dependence on cars, as a case study. The goal is to identify the relationship between the supply of public bus routes and actual work-related commuting patterns. The methodology considers that, given the scarcity of economic resources and prior studies in the Global South, using Geographic Information Systems (GIS) for the spatial analysis of travel is a key tool for redesigning more inclusive and sustainable public transport systems. Specifically, this study utilized origin–destination survey data from 14 urban areas to assess modal coverage, work-related commuting patterns, and the spatial distribution of employment centres. The findings reveal a marked misalignment between the existing public transport network and the population’s travel needs, particularly in marginalized areas. Users face long travel times, multiple transfers, low service frequency, and limited connectivity to key employment areas. This configuration reinforces an exclusionary urban structure, with negative impacts on equity, modal efficiency, and sustainability. The study concludes that GIS-based spatial analysis generates sufficient evidence to redesign the public transport system and reorient urban mobility policy toward sustainability and social inclusion.

The accumulation of plastic waste represents an environmental challenge that affects the construction industry, especially in road paving. In this context, the incorporation of recycled plastics, such as high-density polyethylene (HDPE), was explored to develop more sustainable pavements. The objective of this research was to design and evaluate a replicable methodology to compare traditional asphalt mixtures with mixtures modified with HDPE. To this end, mixtures were prepared using the dry method and subjected to performance tests, including bulk specific gravity (GSB), maximum theoretical specific gravity (Gmm), air void content, and Hamburg wheel tracking test. The results showed that mixtures modified with HDPE exhibited less deformation and maintained porosity levels similar to conventional mixtures, although with a slight decrease in density. It is concluded that the proposed methodology facilitates the integration of recycled plastics into pavements, contributing to waste reduction and improved durability of road infrastructure.

The evaluation of road safety in highway infrastructure requires tools that enable the objective identification and prioritization of risk conditions. This study proposes the development of Severity Indices (SI), a quantitative tool designed to assess the severity level of road segments based on geometric and safety-related variables. Unlike traditional approaches based on qualitative audits, the SI allows for the establishment of severity levels through the integration of measurable and reproducible data. The guiding research question is: How can an index be constructed to quantify the level of road risk based on the physical characteristics of the road and their relationship to crash incidence? To validate the methodology, it was applied to the Centinela–La Rumorosa Highway in Baja California, Mexico—a roadway with high geometric complexity. Variables such as curvature, slope, superelevation, signage, and containment devices were analyzed and correlated with crash records using statistical and spatial analysis in Minitab version 21.1.0. A total of 35 critical points were identified in the descending direction and 28 in the ascending direction, to which SI values were assigned. The results show that this tool allows road safety assessments to be transformed into quantifiable, comparable, and technically informed decision-making processes. The development of the Severity Indices represents a significant methodological contribution to improving road safety evaluation, particularly in contexts where it is necessary to prioritize interventions based on evidence and consistent technical criteria.