EN 1794-2:2020

Road traffic noise reducing devices - Non-acoustic performance - Part 2: General safety and environmental requirements

This document specifies methods and criteria for assessing the general safety and environmental performance of road traffic noise reducing devices under typical roadside conditions. Appropriate test methods are provided where these are necessary. The treatment of each topic is covered separately in Annexes A to E.

Lärmschutzvorrichtungen an Straßen - Nichtakustische Eigenschaften - Teil 2: Allgemeine Sicherheits- und Umweltanforderungen

Dieses Dokument legt Verfahren und Kriterien zur Bewertung von Lärmschutzvorrichtungen hinsichtlich der Sicherheit und des Umweltschutzes im Allgemeinen unter für den Straßenrand typischen Bedingungen fest. Sofern erforderlich, sind geeignete Prüfverfahren angegeben. Diese Aspekte werden in Anhang A bis Anhang E einzeln behandelt.

Dispositifs de réduction du bruit du trafic routier - Performances non acoustiques - Partie 2: Exigences générales pour la sécurité et l'environnement

Le présent document spécifie les méthodes et les critères d’évaluation de la sécurité générale ainsi que des performances relatives à l’environnement des dispositifs de réduction du bruit du trafic routier dans des conditions classiques d'installation en bordure de route. Des méthodes d’essai appropriées sont données chaque fois que cela est nécessaire. Chaque sujet est traité séparément dans les Annexes A à E.

Protihrupne ovire za cestni promet - Neakustične lastnosti - 2. del: Splošne zahteve za varnost in varovanje okolja

General Information

• Status: Withdrawn
• Publication Date: 12-May-2020
• Withdrawal Date: 13-Apr-2025
• ICS: 93.080.30 - Road equipment and installations
• Technical Committee: CEN/TC 226 - Road equipment
• Drafting Committee: CEN/TC 226/WG 6 - Noise reducing devices
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Start Date: 09-Oct-2024
• Completion Date: 14-Apr-2025
• Ref Project: SIST EN 1794-2:2020 - Road traffic noise reducing devices - Non-acoustic performance - Part 2: General safety and environmental requirements

Relations

• Replaces: EN 1794-2:2011 - Road traffic noise reducing devices - Non-acoustic performance - Part 2: General safety and environmental requirements
• Effective Date: 20-May-2020
• Replaced By: EN 1794-2:2024 - Road traffic noise reducing devices - Non-acoustic performance - Part 2: Methods of determination of the general safety and environmental characteristics
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2020
Nadomešča:
SIST EN 1794-2:2011
Protihrupne ovire za cestni promet - Neakustične lastnosti - 2. del: Splošne
zahteve za varnost in varovanje okolja
Road traffic noise reducing devices - Non-acoustic performance - Part 2: General safety
and environmental requirements
Lärmschutzvorrichtungen an Straßen - Nichtakustische Eigenschaften - Teil 2:
Allgemeine Sicherheits- und Umweltanforderungen
Dispositifs de réduction du bruit du trafic routier - Performances non acoustiques - Partie
2 : Exigences générales pour la sécurité et l'environnement
Ta slovenski standard je istoveten z: EN 1794-2:2020
ICS:
13.020.99 Drugi standardi v zvezi z Other standards related to
varstvom okolja environmental protection
17.140.30 Emisija hrupa transportnih Noise emitted by means of
sredstev transport
93.080.30 Cestna oprema in pomožne Road equipment and
naprave installations
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 1794-2
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2020
EUROPÄISCHE NORM
ICS 93.080.30 Supersedes EN 1794-2:2011
English Version
Road traffic noise reducing devices - Non-acoustic
performance - Part 2: General safety and environmental
requirements
Dispositifs de réduction du bruit du trafic routier - Lärmschutzvorrichtungen an Straßen - Nichtakustische
Performances non acoustiques - Partie 2: Exigences Eigenschaften - Teil 2: Allgemeine Sicherheits- und
générales pour la sécurité et l'environnement Umweltanforderungen
This European Standard was approved by CEN on 6 April 2020.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 1794-2:2020 E
worldwide for CEN national Members.

Contents Page
European foreword. 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Symbols . 6
5 Requirements . 7
5.1 Secondary safety (falling debris). 7
5.2 Environmental protection . 7
5.3 Means of escape in emergency . 7
5.4 Reflection of light . 7
5.5 Transparency. 7
6 Test report . 7
Annex A (normative) Secondary safety: danger of falling debris . 8
Annex B (normative) Environmental protection .12
Annex C (normative) Access for maintenance and emergency exits .13
Annex D (normative) Light reflection .15
Annex E (informative) Transparency .17
Bibliography .25

European foreword
This document (EN 1794-2:2020) has been prepared by Technical Committee CEN/TC 226 “Road
equipment”, the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by November 2020, and conflicting national standards
shall be withdrawn at the latest by November 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 1794-2:2011.
This series consists of the following parts under the general title “Road traffic noise reducing devices —
Non-acoustic performance”:
— Part 1: Mechanical performance and stability requirements
— Part 2: General safety and environmental requirements
— Part 3: Reaction to fire - Burning behaviour of noise reducing devices and classification
The main change compared to the previous edition is:
— the suppression of the Annex A, resistance to brushwood fire moved into EN 1794-3.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey
and the United Kingdom.
Introduction
While performing their primary function, road traffic noise reducing devices should not pose hazards
to road users or other people in the vicinity or to the environment at large. Noise reducing devices
should not reflect light in such a way as to prejudice road safety. They should be made from materials
which do not emit noxious fumes or leachates as the result of natural or industrial processes, or as the
result of fire. Noise reducing devices should allow a means of escape by road users and access by
operatives in the event of an emergency or for maintenance.
1 Scope
This document specifies methods and criteria for assessing the general safety and environmental
performance of road traffic noise reducing devices under typical roadside conditions. Appropriate test
methods are provided where these are necessary. The treatment of each topic is covered separately in
Annexes A to E.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
EN 1794-1:2018, Road traffic noise reducing devices - Non-acoustic performance - Part 1: Mechanical
performance and stability requirements
EN ISO 2813, Paints and varnishes - Determination of gloss value at 20°, 60° and 85° (ISO 2813)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
noise reducing device
NRD
system designed to reduce the propagation of traffic noise away from the road environment
Note 1 to entry: The NRD comprises acoustic elements only or both structural and acoustic elements.
Note 2 to entry: applications of NRD include noise barriers, claddings, covers and added devices.
3.2
noise barrier
noise reducing device which obstructs the direct transmission of airborne sound emanating from road
traffic
3.3
acoustic element
element whose primary function is to provide the acoustic performance of the device
3.4
structural element
element whose primary function is to support or hold in place acoustic elements
3.5
cladding
noise reducing device which is attached to a wall or other structure to reduce the amount of sound
reflected
3.6
cover
noise reducing device which either spans or overhangs the road
3.7
added device
additional component that influences the acoustic performance of the original noise-reducing device
(acting primarily on the diffracted energy)
4 Symbols
ϕ angle at which reflections from the surface of the transparent material obscure
m
the view through the material, in degrees;
ϕ angle between the visual axis and the normal to the noise reducing device (see
Figure E.2), in degrees;
ϴ angle of incidence
α angle of transparency (see Figure E.2), in degrees;
n
α angle (see Figure A.1)
ß angle of opacity (see Figure E.2), in degrees;
n
η angle of the transparent Elements
µ terms of refractive index
t function of the angle of incidence
θ
K visual acuity factor (see Figure E.3), in degrees;
A
k Parameter
L light transmission index (as determined in accordance with EN 410 or
T
EN 2155-5), in percent;
’
L overall transparency for different material thickness t’
T
LT/100 coefficient
r radius (see Figure A.1)
S area of opaque features within transparent elements, in square millimetres;
O
S total area of transparent elements, including horizontal features, in square
T
millimetres;
t/t’ material thickness/ different material thickness
T transparency, in percent;
T transparency looking right, in percent;
r
T transparency looking left, in percent;
l
T dynamic transparency, in percent;
D
T static transparency, in percent.
S
u estimated uncertainties
i
u sum of the estimated combined uncertainties
T
u the square of the uncertainty in T
T
w weights
i
5 Requirements
5.1 Secondary safety (falling debris)
When secondary safety has to be assessed, this shall be done in accordance with Annex A.
5.2 Environmental protection
The constituent materials and their breakdown products shall be identified in accordance with
Annex B.
5.3 Means of escape in emergency
The acoustic and mechanical performances of doors or other means of escape shall be assessed in
accordance with Annex C.
5.4 Reflection of light
The results of a standard test of reflectivity shall be assessed in accordance with Annex D.
5.5 Transparency
The results of a standard test of transparency should be assessed in accordance with Annex E.
6 Test report
6.1 Every test report on aspects of performance shall include the following information:
a) number and year of this European Standard;
b) full description of the element or system tested, including manufacturer(s), part numbers, place
and date of origin;
c) description of the method of sampling, if parts of manufactured elements are evaluated by testing;
d) place and date of assessment, and the name of the assessor;
e) sufficient description of any tests carried out, any results measured and the conclusions drawn
about the product together with any illustrations or photographs, all as specified in the
appropriate annex.
6.2 A summary report shall be produced, identifying the aspects of performance for which detailed
reports are available and the level of performance assessed, where appropriate.
Annex A
(normative)
Secondary safety: danger of falling debris
A.1 General
Noise reducing devices can be mounted on structures or in such a way that if damaged they could pose
a hazard to road users or to others. In particular, even if the noise reducing device is protected by the
safety system on an elevated structure, there is a possibility of pieces or whole panels from a noise
barrier becoming detached as the result of a violent collision and for the debris to fall, endangering
those below.
Noise reducing devices which are to be used in a vulnerable position may be required to be restrained
by internal or external linkage between panels and/or elements to prevent them from becoming
detached and falling.
The standard provides some general indications of factors which need to be considered and also
provides a method of establishing the resistance of a product to a severe blow.
NOTE It is principally the responsibility of specifiers to consider the potential consequences of a barrier
becoming damaged and to provide protection accordingly.
Alternatively, a means of catching falling pieces detached from vulnerable barriers may be specified
for barrier systems which are not so restrained.
A.2 Requirements
A.2.1 Behaviour under impact
Where it is known that any component of a device is liable to shatter if struck or shocked, this shall be
clearly stated.
NOTE Such a statement can be qualified by further evidence of the effectiveness of any restraining
mechanism.
A.2.2 Fastening of structural and acoustical elements
A.2.2.1 A noise reducing device shall be assumed to be safety fastened if the elements are secured
in such a way that they do not fall when they are deformed or broken. The restraint systems shall be
designed to withstand the self-weight of the relevant falling parts, multiplied by a load factor of 4. The
wet self-weight shall be used, calculated in accordance with EN 1794-1:2018, Annex B.
A.2.2.2 If structural and acoustical elements of this category of noise reducing device are
prevented from falling by a system of restraint linking them together, each link shall take the load of
all adjoining elements. It shall be assumed that the load applied by broken pieces of a device is the
weight of a single element acting at the most unfavourable position on the restraint system.
A.3 Test method
NOTE This is the test method to access the characteristics of the falling debris produced by fixed energy
impacts.
A.3.1 Principle
The method of testing is to cause a heavy mass to strike normally to the centre or the most sensitive
point of the test specimen or other tested element or system, so that the test specimen is destroyed or
pushed out of the holding structure, or, alternatively to show its behaviour during the test.
A.3.2 Test equipment
The test equipment comprises:
— impactor;
— structure holding the test specimen;
— structure used to produce the impact;
— high speed video camera to record the test.
A.3.3 Impactor
The impactor consists of a rotation symmetrical full steel double cone.
The impactor shall conform to the shape and details shown in Figure A.1 and the relation to their
impact energy in Figure A.2.
A.3.4 Test specimen
The test specimen shall be assembled in the supporting structure in the way intended by the
manufacturer, including: dimensions, fixings, seals and any connecting systems. Elements or systems
with integrated or attached restraint structure shall be tested as complete units.
A.3.5 Structure holding the test specimen
The structure holding the test specimen shall be designed to be able to withstand the whole impact
energy as described in A.3.7. In all cases the structure shall allow a good camera position for proper
documentation.
A.3.6 Structure used to produce the impact
The impact shall be produced by a pendulum. The impactor shall swing on 2 wires fixed on 2 points
above the structure holding the test sample as shown in Figure A.2. In order to reach the impact energy
of 6,0 kJ, the height of the fall of the impactor with 400 kg shall be 1,50 m, corresponding to a speed of
19,5 km/h. In order to reach the impact energy of 0,5 kJ, the height of the fall of the impactor with
45 kg shall be 1,10 m, corresponding to a speed of 16,7 km/h. The radius of the pendulum shall be
minimum 4,0 m in both cases.
A.3.7 Evaluation
A.3.7.1 General
Only the falling debris caused by the first impact shall be taken into account. The performance shall be
expressed as a level according to Table A.1.
NOTE This can be achieved for example by restraining the pendulum after the first impact or by proper
analysis of the video documentation.
A.3.7.2 Assessment criteria for free pieces
No rigid pieces of test specimen larger than 25 cm weighing more than 0,100 kg.
No rigid pieces of test specimen longer than 15 cm.
No rigid pieces with angles of less 15° and weighing more than 0,100 kg.
No pieces weighing more than 0,400 kg.
No rigid sharp pieces thinner than 1 mm and weighing more than 0,100 kg.
A.3.7.3 Results
A: Free pieces not meeting the criteria.
B: Free pieces meeting the criteria.
C: No pieces at all.
A.3.7.4 Classification
Table A.1 — Classification
Class Test Result
(kJ)
0 Not passed / A
1 0,5 B
2 0,5 C
3 6,0 B
4 6,0 C
A.3.8 Test report
The test report shall include a full description of the test arrangement, including details of supports,
procedures and location of points of impact.
It shall also include:
a) number and year of this European Standard, i.e. EN 1794-2:2020;
b) name and address of the testing institute with a dated signature of the person responsible;
c) exact identification of the tested element, the name and address of the manufacturer;
d) full description of the materials and their thicknesses;
e) drawing showing the cross section of the tested element;
f) results of tests and the resulting classification; any pieces not meeting the criteria shall be
reported;
g) development and the effect of every impact shall be documented by means of high-speed video
cameras and photos;
h) any damages to the sample like cracks and deformations should be described and documented.
Radius in millimetres
Figure A.1 —Impactor
Key
1 height for getting 6 kJ with 400 kg impac
...