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Overview

Containment

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Impact Severity

Overview of EN1317 Compliance
EN1317 is the current European standard for Road Restraint Systems.

All safety restraint systems offered by Extrudakerb are tested and certified to meet the requirements of EN1317.

Britpave Concrete Barrier systems comply with EN1317, they are certified with H2 and N2 Containment levels, W1 and W2 Working Width, ASI Level B Impact Severity, Complaint transition and termination details.

EN1317 is the current European standard for Road Restraint Systems. EN1317 comprises 6 parts.

EN1317-1 defines the terminology used and general criteria for test methods

Parts 2, 3 and 4 define the performance classes, impact test acceptance criteria and test methods for

·         safety barriers (EN1317-2)

·         crash cushions (EN1317-3)

·         terminals, transitions (EN1317-4)

Part 5 defines product requirements, durability and evaluation of conformity (EN1317-5) and Part 6 parapets for pedestrians (EN1317-6)

The Road Overseeing Authorities of European member countries are obliged to provide newly built safety restraint systems complaint with the requirements of EN1317.

Road Overseeing Authorities or agents acting for them, such a designers, should evaluate the requirements of a highway – including geometry, traffic flows, speeds and types, the existence and location of hazards as well as the width of the median, and specify a minimum road restraint system performance level.

Road Overseeing Authorities must also ensure compliance with EN1317 requirements for Safety Restraint System transition, termination and alignment change.

Containment, working width and ASI classes shall be specified. The highway maintenance or construction contractor shall then select a road restraint system that meets the specified minimum performance level and provides best value.

Best value should include consideration of not only initial installation cost but also, whole life and maintenance cost as well as environmental impact.

Britpave Concrete Barrier systems comply with EN1317, they are certified with

·         H2 and N2 Containment levels

·         W1 and W2 Working Width

·         ASI Level B

·         Complaint transition and termination details

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Gallery

Related Pages

Overview

Containment

Working Width

Impact Severity

Containment
Containment provides an indication of the magnitude of vehicle impact that a safety restraint system can withstand without failure.

EN1317 provides a variety of vehicle crash tests with differing vehicle type, mass, speed and angle of impact.

The higher the containment level the greater the barrier’s ability to restrain and redirect an errant vehicle.

Britpave Concrete Step Barrier (CSB) and Steel Step Barrier (SSB) systems were tested and certified to have a Containment Levels Class H2 and N2.

The Working Width of the barrier system is also measured during crash test and a working width relates to a containment level. CSB and SSB have working widths of W2 at H2 containment and W1 at N2 containment.

 

 Table detailing crash test and the relevant vehicle, mass, speed at impact and angle of impact

View the H2 containment crash test.

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Gallery

Related Pages

Overview

Containment

Working Width

Impact Severity

Working Width
Working Width provides an indication of the environment within which a safety barrier operates at a given Containment Level.

EN1317 provides a variety of vehicle crash tests with differing vehicle type, mass, speed and angle of impact and at each crash the Working Width will be measured.

The Working Width of the safety restraint system is defined as the greater of:

·         the measurement of the footprint of the safety restraint system

·         the measurement of the dynamic deflection of the safety restraint system when impacted

·         the measurement of vehicle overhang at impact

The H2 containment test shows that even at this high level of impact dynamic deflection is zero.

The centre of gravity of the bus does not cross the centreline of the barrier and the vehicle is safely re-directed.

As Britpave CSB and SSB are available in a number of sizes the working width of the system varies.

The higher the containment level the greater the barrier’s ability to restrain and redirect an errant vehicle.

Britpave Concrete Step Barrier (CSB) and Steel Step Barrier (SSB) systems were tested and certified to have a Containment Levels Class H2 and N2.

The Working Width of the barrier system is also measured during crash test and a working width relates to a containment level. CSB and SSB have working widths of W2 at H2 containment and W1 at N2 containment.

Page : 62

Gallery

Related Pages

Overview

Containment

Working Width

Impact Severity

Impact Severity
Impact severity provides an indication of the collision consequences for vehicle passengers following impact with a road restraint system.

Three measurements are taken during an EN1317, TB11 (900kg car) crash test: one being a measurement of Acceleration Severity Index (ASI, anotherTheoretical Head Impact Velocity (THIV) and the third Post-Impact Head Deceleration (PHD).

Road restraint systems are classified only by the recorded ASI measurement. However both THIV and PHD must be recorded at measurements below defined safe thresholds.

Britpave Concrete Step Barrier (CSB) and Steel Step Barrier (SSB) systems were tested and certified to have an Impact Severity Class B.

For many years ASI has, in some parts, been considered to be the only measure of a road restraint systems safeness and performance level; with containment and working width ignored.

Recently world renowned experts are beginning to question this. Richard Sturt, Director at Ove Arup & Partners recently published paper in the International Journal of Crashworthiness concludes that in fact although ASI did show a correlation with injury risk, the level chosen for the boundary between class B and C barriers in EN1317 does not provide significant discrimination between higher and lower risk of injury.

Download “The relationship of injury risk to accident severity in impacts with roadside barriers” by Richard Sturt.

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