BS EN 1317: Road restraint system

BS EN 1317 is a European standard that deals with road restraint systems, which are designed to safeguard road users and vehicles from hazards, such as barriers, crash cushions, and guardrails. It specifies the requirements for the design, performance, and testing of these systems to ensure they effectively reduce the severity of impacts in the event of a collision. The full title of the standard is “BS EN 1317: Road restraint systems”.

Key aspects of BS EN 1317 include:

1. Scope:
   • The standard applies to road restraint systems such as barriers (guardrails, crash barriers), vehicle parapets, and terminals designed to protect road users in case of an accident.
   • It covers systems used in various environments, including highways, rural roads, and urban roads.
2. Performance Classes:
   • BS EN 1317 categorizes systems based on their performance in crash tests. These include:
     • Containment classes: These classify the ability of the system to contain vehicles and prevent them from crossing into dangerous areas. Classes range from N1 (low containment) to H4a (high containment).
     • Impact severity classes: These classify the severity of the impact that the system will absorb, from A (lower severity) to E (higher severity).
     • Working width: This defines the lateral clearance required for the system to function properly without affecting other road users or infrastructure.
3. Testing and Evaluation:
   • The standard outlines specific tests to evaluate the performance of road restraint systems, such as:
     • Crash tests involving different types of vehicles, including cars and trucks.
     • Testing for impact severity, deflection, and other safety parameters.
   • These tests ensure that the system can contain vehicles safely, prevent overturning, and reduce the risk of injury to occupants.
4. Design Requirements:
   • The design of the systems is influenced by factors such as road geometry, vehicle types, traffic volume, and the risk of accidents.
   • The system must prevent vehicles from crossing into opposite lanes, off the road, or into dangerous areas such as steep drops or water bodies.
5. Materials and Durability:
   • Road restraint systems must be designed using durable materials that can withstand environmental conditions (weather, corrosion, wear and tear).
   • Material strength, resistance to environmental factors, and the system’s ability to remain intact after multiple impacts are considered.
6. Impact Absorption:
   • The standard emphasizes the importance of reducing the severity of vehicle impact on both the vehicle and its occupants. Road restraint systems must absorb and dissipate the energy of an impact to prevent injury.
7. Installation and Maintenance:
   • Proper installation and regular maintenance are crucial to the effectiveness of the system. The standard specifies guidelines for how systems should be installed and maintained to ensure they remain functional and safe over time.
8. Categories of Road Restraint Systems:
   • The systems are divided into several categories, such as:
     • Rigid barriers: These are typically made of concrete or steel and are used for high-containment scenarios.
     • Flexible barriers: Made of materials like wire rope or mesh, these systems can absorb impact energy and are typically used in less critical zones.
     • Crash cushions: These are designed to protect road users from collisions with fixed objects, such as bridge supports or signposts.

BS EN 1317 Parts:

The standard is made up of several parts that focus on different aspects of road restraint systems:

• Part 1: Terminology and general requirements.
• Part 2: Performance requirements and classification.
• Part 3: Testing and evaluation procedures.
• Part 4: Installation and maintenance guidelines.

By adhering to BS EN 1317, road authorities and designers ensure that road restraint systems provide high levels of safety, performance, and reliability.