Open    Access



Risk-Based Evaluation of Longitudinal Ventilation with Enhanced Safety Concept



Author(s)

Göran Nygren

Full-Text PDF XML     13 Views

DOI:10.17265/1934-7359/2025.09.003

Brandingenjör & Civilingenjör i Riskhantering, WSP Brand & Risk, 111 64 STOCKHOLM, Sweden

The longitudinal ventilation strategy is commonly used for road tunnels in urban environment in Sweden. This is partly due to how tunnels in urban environment was planned and designed before the EU Directive (2004/54/EC) came in place. Even in new tunnels both to practical and economic reasons the use of longitudinal ventilation has been an outspoken demand from the Swedish road authority, SRA. Swedish law requires that a risk analysis is carried out to demonstrate that an acceptable level of risk is achieved in the tunnels with longitudinal ventilation if there is a risk of queues. Otherwise transverse or semi-transverse ventilation strategy shall be used. During recent development, or a late awakening, it is clear that dense populated areas in Sweden will experience queues. This threatens the foundation of the Swedish modern tunnel safety concept which calls for enhancement. This paper presents the risk-reducing effect of three alternative strategies, enhancements package, focusing on evacuation safety for road users. It is a combination of traffic management, fixed firefighting systems, reduced distance between escape routes and regulation of traffic with dangerous goods. In addition, it provides a comprehensive review of safety system details, combined with a longitudinal ventilation concept. 

Longitudinal ventilation, queue, risk assessment, risk mitigation measures, safety concept.

Journal of Civil Engineering and Architecture 19 (2025) 433-443

doi: 10.17265/1934-7359/2025.09.003