INFORMAL TRAFFIC SIGNALS AND ROAD SAFETY GOVERNANCE IN SOUTHEAST ASIAN CITIES

Abstract

Road safety remains a major challenge in motorcycle-dominant cities across Southeast Asia, where dense mixed traffic requires continuous negotiation among road users. This study examines how informal traffic communication practices among motorcyclists function as culturally interpreted coordination mechanisms in urban traffic environments. Using a mixed-method approach, the research integrates survey data from 834 Malaysian motorcyclists with comparative observation from Indonesia, Vietnam, and Bangladesh, complemented by stakeholder focus group insights. The findings show that riders routinely employ several informal signalling practices, including polite horn taps, head nods, hand gestures, and empathetic yielding behaviours. Among these, yielding behaviour and short horn signals emerged as the most common coordination strategies for managing uncertainty and avoiding conflict. Respondents also strongly agreed that informal interaction improves traffic flow, reduces misunderstanding, and contributes to safer road environments. Cross-country comparison indicates that the interpretation and intensity of such signals vary across traffic cultures, suggesting that informal communication operates as a locally embedded behavioural system rather than a universal rule. The study argues that integrating behavioural communication awareness into rider education and urban transport policy could enhance safety outcomes in motorcycle-dense cities. By framing traffic interaction as a social communication process, the research contributes to broader efforts supporting SDG 3 Good Health and Well-Being through the reduction of traffic accidents, and SDG 11 Sustainable Cities and Communities through safer and more inclusive urban transportation systems.