EN 15518-3:2023

SLOVENSKI STANDARD
01-februar-2024
Oprema za zimska vzdrževalna dela - Cestni vremensko-informacijski sistemi - 3.
del: Zahteve za merjene vrednosti pri stacionarni opremi
Winter maintenance equipment - Road weather information systems - Part 3:
Requirements on measured values of stationary equipment
Winterdienstausrüstung - Straßenzustands- und Wetterinformationssysteme - Teil 3:
Anforderungen an gemessene Werte der stationären Anlagen
Matériels de viabilité hivernale - Systèmes d'information météorologique routière - Partie
3 : Exigences relatives aux valeurs mesurées par des matériels fixes
Ta slovenski standard je istoveten z: EN 15518-3:2023
ICS:
07.060 Geologija. Meteorologija. Geology. Meteorology.
Hidrologija Hydrology
13.030.40 Naprave in oprema za Installations and equipment
odstranjevanje in obdelavo for waste disposal and
odpadkov treatment
35.240.99 Uporabniške rešitve IT na IT applications in other fields
drugih področjih
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 15518-3
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2023
EUROPÄISCHE NORM
ICS 07.060; 13.030.40; 35.240.99 Supersedes EN 15518-3:2011
English Version
Winter maintenance equipment - Road weather
information systems - Part 3: Requirements on measured
values of stationary equipment
Matériels de viabilité hivernale - Systèmes Winterdienstausrüstung - Straßenzustands- und
d'information météorologique routière - Partie 3 : Wetterinformationssysteme - Teil 3: Anforderungen an
Exigences relatives aux valeurs mesurées par des gemessene Werte der stationären Anlagen
matériels fixes
This European Standard was approved by CEN on 18 September 2023.

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, Türkiye 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
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 15518-3:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
3.1 Road parameters . 6
3.2 Atmospheric parameters . 7
3.3 General. 8
4 Requirements . 9

European foreword
This document (EN 15518-3:2023) has been prepared by Technical Committee CEN/TC 337 “Road
operation equipment and products”, 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 May 2024, and conflicting national standards shall be
withdrawn at the latest by May 2024.
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 15518-3:2011.
— added definition and requirements for:
— freezing temperature;
— ice;
— hoar frost;
— ice film thickness;
— snow layer thickness;
— differentiation between embedded and remote (non-invasive) road sensors and specific
requirements for:
— road surface temperature;
— road surface condition;
— water film thickness;
— ice film thickness (only for remote sensors);
— snow layer thickness (only for remote sensors);
— adaptation of the definition and differentiation between active and passive measurement methods
in the requirements for freezing temperature;
— added requirements for:
— amount of de-icing agent;
— amount of precipitation;
— adaption of requirements for:
— road body temperature;
— air temperature;
— relative humidity;
— precipitation intensity;
— removed requirements for snow height (on and next to the road).
EN 15518, Winter maintenance equipment — Road weather information systems, is currently composed
with the following parts:
— Part 1: Global definitions and components;
— Part 2: Road weather — Recommended observation and forecast;
— Part 3: Requirements on measured values of stationary equipment;
— Part 4 (CEN/TS): Test methods for stationary equipment.
A list of all parts in a series can be found on the CEN website: https://www.cencenelec.eu/.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
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, Türkiye and the United
Kingdom.
Introduction
Road Weather Information Systems (RWIS) are complex structures used for road maintenance decision
support, which feature as a rule the following components: meteorological sensors and instruments, road
condition sensors (embedded or remote), transmission technology, computer systems for processing,
representation and storing of information, road weather forecasts and alarms, in relation to traffic control
and traffic information systems and more.
A stationary road weather station performs the acquisition of road and meteorological information at a
fixed location.
This document lays down the requirements for the recommended sensor components of a road weather
station of a Road Weather Information System (RWIS). In the description of requirements, a distinction
is made between the sensor components forming a basis road weather station for winter use and the
recommended complementary optional sensor components.
Parameters which are not in the standard but offered on the market could be useful but are left out of this
minimum standard due to the fact that there are currently no professional methods available to verify
these parameters.
The aim is to ensure extensive combination and interchangeability within the systems.
With a set terminology for the components and the meteorological expressions an attempt is made to
counteract a diversity of terms and designations for identical phenomena.

1 Scope
This document specifies the terminology and performance requirements for all sensor components of
stationary equipment within a Road Weather Information System (RWIS).
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 15144, Winter maintenance equipment — Terminology — Terms for winter maintenance
CEN/TS 15518-4, Winter maintenance equipment — Road weather information systems — Part 4: Test
methods for stationary equipment
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 15144 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
NOTE The following definitions have been established specifically for the RWIS domain.
3.1 Road parameters
3.1.1
pavement surface temperature
effective radiation temperature of a pavement surface and the contaminant
layer; conductive temperature on the pavement surface
3.1.2
road body temperature
temperature of the road in a specific depth in the construction layers
3.1.3
amount of de-icing agent
mass of de-icing agent on a road surface per square metre
3.1.4
freezing temperature
temperature at which a liquid begins to freeze on a road surface
Note 1 to entry: The requirement specifications for freeze temperature in this document are valid under well-
known and reproducible laboratory environment conditions. The real environment condition on a road under
traffic result in high variations due to the highly variable distribution of water film and de-icing agent concentration
over the pavement surface and a lot of other influences like traffic, solar radiation, surface slope, etc.
3.1.5
road surface condition
qualification of the status of road surface affected by road weather phenomenon
3.1.6
water film thickness
mean thickness of the film of water present on a flat surface, measured on a specific measurement area
observed by a sensor
Note 1 to entry: If a sensor provides also ice film and snow layer thickness, then this parameter means the liquid
portion. If a sensor doesn’t provide ice film and snow layer thickness, then water film thickness means all kind of
water content (water equivalent).
3.1.7
ice
water on a surface freeze from a liquid state to solid state, if surface temperature drops down below
freezing temperature (3.1.4) or if liquid precipitate falls on a surface whose temperature is below freezing
and immediately freezes into solid state
3.1.8
hoar frost
ice crystals deposit formed from contact of airborne moisture with a surface whose temperature is below
freezing
Note 1 to entry: Hoar frost differs from ice in that the frost crystals grow independently and, therefore, have a more
granular texture. Currently known surface sensor technologies are not able to detect Hoar Frost directly. The
condition can only be classified by the measuring station with the help of atmospheric sensors.
3.1.9
ice film thickness
mean thickness of the film (or layer) of ice (water equivalent of frozen water) present on a flat surface,
measured on a specific measurement area observed by a sensor
3.1.10
snow layer thickness
approximative layer of snow (water equivalent of snow) present on flat surface, measured on a specific
measurement area observed by a sensor
Note 1 to entry: Snow layer thickness gives an indication about the layer of snow, but accuracy cannot be defined
nor verified.
3.2 Atmospheric parameters
3.2.1
relative humidity
RH
measure of how much water vapor is in a water-air mixture compared to the maximum amount possible
3.2.2
precipitation
falling water from the atmosphere in liquid and/or solid form which can be observed and measured on
ground
3.2.3
rain
precipitation in liquid form
3.2.4
snow
water vapour in the atmosphere that has been condensed directly into ice without going through the
liquid state
Note 1 to entry: The small ice crystals absorb and freeze additional water vapor from surrounding air, growing into
snow crystals. The clusters of snow crystals are formulated into snowflakes.
3.2.5
amount of precipitation
thickness of the layer of water obtained by precipitation (rain or melted solid precipitation) on a
horizontal surface
3.2.6
intensity of precipitation
amount of precipitations per unit of time
3.2.7
wind speed
distance which traverses the air per unit of time
Note 1 to entry: Wind speed is either instantaneous or mean wind.
3.2.8
gust of wind
sudden and transient strengthening of the wind, resulting in a brief and sudden increase in the
instantaneous wind speed (3.2.7), compared to the value achieved by its mean wind
3.2.9
wind direction (instantaneous and
...