CEN/TS 15518-4:2013

SLOVENSKI STANDARD
01-maj-2013
Oprema za zimska vzdrževalna dela - Cestni vremensko-informacijski sistemi - 4.
del: Preskusne metode za stacionarno opremo
Winter maintenance equipment - Road weather information systems - Part 4: Test
methods for stationary equipment
Winterdienstausrüstung - Straßenzustands- und Wetterinformationssysteme - Teil 4:
Prüfverfahren bei stationären Einrichtungen
Matériel de viabilité hivernale - Systèmes d'information météorologique routière - Partie
4 : Méthodes d'essai pour les matériels fixes
Ta slovenski standard je istoveten z: CEN/TS 15518-4:2013
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 8SRUDEQLãNHUHãLWYH,7QD IT applications in other fields
GUXJLKSRGURþMLK
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL SPECIFICATION
CEN/TS 15518-4
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
March 2013
ICS 07.060; 13.030.40; 35.240.99
English Version
Winter maintenance equipment - Road weather information
systems - Part 4: Test methods for stationary equipment
Matériel de viabilité hivernale - Systèmes d'information Winterdienstausrüstung - Straßenzustands- und
météorologique routière - Partie 4 : Méthodes d'essai pour Wetterinformationssysteme - Teil 4: Prüfverfahren bei
les matériels fixes stationären Einrichtungen
This Technical Specification (CEN/TS) was approved by CEN on 30 July 2012 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.

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

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 15518-4:2013: E
worldwide for CEN national Members.

Contents Page
Foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Type reception test definition . 5
3.1 Introduction . 5
3.2 Pavement surface temperature . 6
3.3 Road surface condition . 10
3.4 Water film thickness . 16
3.5 Freezing temperature . 17
3.6 Road body temperature . 21
3.7 Air temperature . 21
3.8 Relative humidity . 23
3.9 Dew point temperature . 25
3.10 Precipitation detection time . 25
3.11 Precipitation type . 26
3.12 Precipitation intensity . 27
3.13 Snow depth. 28
3.14 Wind speed . 28
3.15 Gust of wind . 29
3.16 Wind direction . 29
3.17 Visibility . 31
Bibliography. 33

Foreword
This document (CEN/TS 15518-4:2013) has been prepared by Technical Committee CEN/TC 337 “Winter
maintenance and road service area maintenance equipment”, the secretariat of which is held by AFNOR.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document Winter maintenance equipment  Road weather information systems comprises of 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 equipments;
 Part 4: Test methods for stationary equipment (the present document).
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Croatia, Cyprus,
Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey 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,
transmission technology, computer systems for processing, representation and storing of information, road
weather forecasts, alarms, in relation to traffic control and traffic information systems and more.
This European Specification lays down the test procedures to verify the requirements on stationary equipment
defined in EN 15518-3.
The aim is to allow for objective and reproducible measurement analysis and evaluation.
1 Scope
This Technical Specification specifies the test methods, the experimental set-up and result analysis for the
laboratory qualification of stationary equipment within a RWIS.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
EN 13108-5, Bituminous mixtures — Material specifications — Part 5: Stone Mastic Asphalt
EN 15518-3, Winter maintenance equipment — Road weather information systems — Part 3: Requirements
on measured values of stationary equipments
EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
(ISO/IEC 17025)
ISO 17714, Meteorology — Air temperature measurements — Test methods for comparing the performance
of thermometer shields/screens and defining important characteristics
3 Type reception test definition
3.1 Introduction
3.1.1 General
The tests described hereafter apply to either a complete system (which can influence the measured value)
consisting of sensor, processing electronics and associated terminal program software necessary to acquire,
display and store the measurements in a digital form, or to some specific parts of the whole system when the
inputs can be simulated, as specified by the manufacturer. Figure 1 below is an illustration of the possible
functional components of a system.
The manufacturer shall specify and supervise the material set-up for the test set-up.
The manufacturer may not change the test set-up during the tests. The data shall be readable during the
whole test. The whole test shall stop in case the manufacturer changes the test set-up.
If a single sensor provides measurements subject to more than one test procedure, it shall always be tested
against all these procedures within the same test campaign and by the same laboratory. This is also valid for
tests after technical changes to a sensor.

Figure 1 — Possible functional components of a system
Test protocols shall state the version and type of hardware, firmware and software components as well as the
material set-up during the test.
In case of major technical changes to one or other of these components which affect the requirements of
EN 15518-3, the manufacturer shall seek new certification. In case of minor changes not affecting the
requirements of EN 15518-3, the manufacturer shall indicate the changes and, upon request, provide the
demonstration that the changes did not affect in an adverse way the system which was originally tested and
that the new system still meets the standard.
In general, if a sensor was tested as a single device, met the requirements of this standard, and its nominal
output can be simulated, the RWIS manufacturer shall be allowed to demonstrate only that the measuring
chain cannot influence the raw signal in a manner to exceed the allowed tolerance. This has to be confirmed
by an accredited laboratory.
Therefore, this standard applies to three possible configurations:
 sensor as single device;
 electronics with simulated sensor inputs;
 complete system.
3.1.2 Test body
Wherever stated, the sensor shall be permanently installed in the centre of a test body according to the
manufacturer’s specifications, which shall be part of the test report. The characteristics of the test body are:
a) Minimal dimensions 600 mm by 400 mm surface and 200 mm depth. There shall be a minimal distance of
15 cm between each side of the sensor (including sealing compound, in all three dimensions) and the
side of the test body. This shall be documented in the test report.
b) Realisation: Under similar conditions than road construction, having the following characteristics:
1) material: Asphalt Concrete (heavy traffic road);
2) layer: one single mixture (surface course) in three or more layers, the upper layer being 6 cm deep;
3) EN 13108-5, Bituminous mixtures — Material specifications — Part 5: Stone Mastic Asphalt:
i) grading rate: 8 mm:  100 %;
5,6 mm:  90 % to 100 %;
2 mm:  20 % to 40 %;
0,063 mm: 5 % to 12 %;
ii) binder rate:  B ;
min7,4
iii) maximum cavity rate: V ;
max3
iv) minimum cavity rate: V .
max2
Other test bodies may be defined and used in case of specific needs. The type and characteristics of the test
bodies shall be mentioned in the test report.
3.2 Pavement surface temperature
3.2.1 General
This test shall be realised under stabilised and transient temperatures (see below).
Unless otherwise specified, a valid measurement value shall be delivered by the system at latest 6 min after
the test conditions are met.
3.2.2 Test method
3.2.2.1 Stabilised temperature test
The sensor is plunged into a liquid bath set at stabilised temperatures. The temperature response of the
sensor is compared to the temperature response of a reference thermometer.
The test does not apply to sensors working without contact.
3.2.2.2 Transient surface temperature test
The test shall take place in a cooled climatic chamber. The sensor shall be installed in a test body as per 3.1.2
above. Reference probes shall be installed on the surface of the test body in a manner to reduce as much as
possible the influence of direct radiation.
A radiation source (2 halogen lamps) is switched on for a given time to simulate road heating by solar
radiation and cooling by emissivity.
The temperature response of the sensor shall be compared to the temperature response of the reference
probes.
3.2.3 Test equipment
3.2.3.1 Stabilised temperature test
This test requires the following equipment:
 container with liquid solution (car cooling liquid or saline solution);
 apparatus for cooling and stabilising this liquid in a container within the expressed requirements
(“cryostat”);
 reference thermometer with accuracy ± 0,1 °C and sampling rate of maximum 10 s.
3.2.3.2 Transient temperature test
This test requires the following equipment:
 climatic chamber;
 2 x 500 W Halogen lamps placed as per Figure 2 below and aiming at the centre of the test body;
 test body as per 3.1.2 above;
 3 PT 100 reference probes with polling interval less than half that of the sensor to be tested. The
reference probes shall be installed horizontally in the test body in a groove 3 mm deep and covered with
bitumen. They shall be located in an equilateral triangle around the sensor to be tested, each one being
no more than 5 cm away from the border of the sensor to be tested (see Figure 2 below).
Dimensions in centimetres
Key
1 500 W Halogen lamps
2 test body (see 3.1.2)
3 3 PT reference probes
Figure 2 — Set-up for transient temperature test
3.2.3.3 Stabilised temperature test
Ensure a proper connection of the sensor to be tested and the whole measurement chain. The measurements
of the sensor and the reference thermometer shall be recorded throughout the test.
Set the bath to the given temperature; ensure a uniform temperature of the bath (difference < 0,1 °C) by
stirring the liquid. The temperature variation of the bath shall not exceed ± 0,1°C throughout the duration of
each test.
Plunge the sensor into the liquid bath so that it does not touch the bottom or the walls of the container.
The measurement period shall start at soon as one of the following conditions is met:
 a first measurement of the sensor to be tested is recorded within the required accuracy;
 the reference thermometer has shown bath temperatures within requirements for 6 min.
The measurement period ends as soon as one of the following conditions is met:
 5 consecutive samples (or all the samples during 10 min, whichever is longer) of the sensor to be
tested are recorded within the accuracy requirements;
 15 samples of the sensor to be tested (or 30 min, whichever is longer) have elapsed since the start of
the measurement period.
The test shall be performed at each of the following temperatures (more test points can be added):
 10 °C;
 0 °C;
 -15 °C.
3.2.3.4 Transient temperature test
Ensure a proper connection of the sensor to be tested and the whole measurement chain.
The measurements of the sensor to be tested and the reference probes shall be recorded throughout the test.
The climatic chamber (including the test bloc) shall be set to a stabilised environmental temperature of -5 °C.
The climatic situation in the chamber shall remain constant throughout the test.
Before the start of the test, all the reference probes shall indicate a temperature of -5 °C ± 0,2 °C.
Switch on the halogen lamps. As soon as a surface temperature ≥ 10 °C is indicated by all the reference
probes, the halogen lamps shall be switched off.
The measurements of the tested sensor and the reference probes shall be further recorded for a duration of
5 min after a surface temperature ≤ 0 °C has been indicated by all the reference probes.
3.2.4 Result analysis
3.2.4.1 Stabilised temperature test
The test is considered successful if five consecutive samples (or all the samples during a period of 10 min,
whichever is longer) are recorded within the accuracy requirements, specified in EN 15518-3.
3.2.4.2 Transient temperature test
The measurements recorded from the reference probes and the sensor to be tested shall be displayed in a
graph similar to Figure 3 below. Great attention shall be paid to the synchronisation of measurements before
the analysis of the results.
A first allowed variation area shall be set around the highest temperature(s) measured by the reference
probes (the reference value is the mathematical average between the values of the three reference probes).
The allowed temperature variation (vertical axis) for this area shall be ± 2 °C. The allowed time variation
(horizontal axis) for this area shall be ± 3 min.
A second variation area shall be set around the 0 °C temperature measured by the reference probes (the
reference value is the mathematical average between the values of the three reference probes). The allowed
temperature variation (vertical axis) for this area shall be ± 2 °C. The allowed time variation for this area
(horizontal axis) shall be ± 3 min.
NOTE The definitive time and temperature variation values will be defined with the final standard.
Key
1 measurement record of reference probes
2 measurement record of the tested sensor
3 allowed time variation
4 allowed temperature variation
5 allowed time variation
6 allowed temperature variation
T temperature
t time
Figure 3 — Result analysis of transient temperature test
The test is considered successful if both following conditions are met:
 the highest temperature recorded from the sensor to be tested lies inside the first variation area;
 there is at least one measured value recorded from the sensor to be tested inside the second variation
area.
Alternative: The output curve of the sensor to be tested touches the second variation area with at least one
point.
3.3 Road surface condition
3.3.1 General
Unless otherwise specified, a valid measurement value shall be delivered by the system at latest 6 min after
the test conditions are met.
3.3.2 Test method
3.3.2.1 General
The test shall take place in a climatic chamber. The sensor shall be installed in a test body as per 3.1.2 above.
3.3.2.2 Dry
The climatic chamber shall be set to ensure stabilised conditions (avoiding condensation) below 0 °C.
The output of the sensor to be tested shall be compared with the condition “Dry”.
3.3.2.3 Moist
The climatic chamber shall be set to ensure stabilised conditions (avoiding condensation) at two different
temperatures (above and below 0 °C).
A liquid film thickness corresponding to the requirement “Moist” of EN 15518-3 shall be applied and
maintained over the sensor.
The output of the sensor to be tested shall be compared with the condition “Moist”.
3.3.2.4 Wet
The climatic chamber shall be set to ensure stabilised conditions (avoiding condensation) at two different
temperatures (above and below 0 °C).
A liquid film thickness corresponding to the requirement “Wet” of EN 15518-3 shall be applied and maintained
over the sensor.
The output of the sensor to be tested shall be compared with the condition “Wet”.
3.3.2.5 Streaming water
The climatic chamber shall be set to ensure stabilised conditions (avoiding condensation) above 0 °C.
A liquid film thickness corresponding to the requirement “Streaming water” of EN 15518-3 shall be applied and
maintained over the sensor.
The output of the sensor to be tested shall be compared with the condition “Streaming water”.
3.3.2.6 Slippery
The road status “Slippery” is reached when the pavement surface temperature is equal or below the freezing
point temperature of the solution on the pavement, or when solidified water appears over the pavement.
 Phase one:
The climatic chamber shall be set to ensure stabilised conditions (avoiding condensation) above 0 °C.
A liquid film thickness with predetermined freezing point temperature shall be applied and maintained over the
sensor. The temperature of the climatic chamber shall then be gradually brought to a temperature below or
equal to the freezing point temperature in the climatic chamber.
The output of the sensor to be tested shall be compared with the condition “Slippery”.
 Phase two:
The climatic chamber shall be set to ensure stabilised conditions (avoiding condensation) below 0 °C.
Warmer air shall be brought in the climatic chamber by opening the doors, creating the deposit of ice crystals
(hoarfrost) over the test body.
The output of the sensor to be tested shall be compared with the condition “Slippery”.
3.3.3 Test equipment
This test requires the following equipment:
 spreading equipment (accuracy better or equal to ± 10 % for a thickness of 0,01 mm) to provide
controlled thicknesses of liquid solutions over the sensor;
 climatic chamber;
 precision scale with a plate of known surface (thoroughly cleaned before each test);
 reference temperature probe (air and pavement);
 test body as per 3.1.2 above;
 rain water (has to ensure correct wettability);
 NaCl solution;
 towel and fan.
3.3.4 Test procedure
3.3.4.1 General
The sequence of the tests may be modified in order to avoid repeated temperature changes in the climatic
chamber.
3.3.4.2 Dry
Ensure a proper connection of the sensor to be tested and the whole measurement chain.
Set the climatic chamber to a temperature of -5 °C. Dew point temperature shall be at least 1 °C below the air
temperature to avoid condensation. The temperatures of air and sensor shall be identical and stabilised.
Using a towel and a fan, clean and dry the surface of the sensor.
Start the recording of the surface condition measurements.
Five samples or 10 min (whichever is longer) after the first reported road surface condition “Dry”, stop the
recording of the surface condition measurement.
3.3.4.3 Moist
Ensure a proper connection of the sensor to be tested and the whole measurement chain.
Set the climatic chamber to a temperature of 5 °C. Dew point temperature shall be at least 1 °C below the air
temperature to avoid condensation. The temperatures of air and sensor shall be identical and stabilised.
Install the precision scale close to the sensor to be tested under the spreading device. The mass of liquid
applied over the surface of the plate of the scale is recorded and converted to liquid thickness. This value
serves as reference for the test.
Using a towel and a fan, clean and dry the surface of the sensor.
Start the recording of the surface condition measurements.
Apply a water film thickness between 0,012 mm and 0,015 mm over the sensor and the plate of the precision
scale. This water film thickness has to remain constant for 6 min, or until the road surface condition
measurement shows “Moist”, whichever is first.
Then, enough water shall be applied as needed to keep the water film thickness between 0,01 mm and
0,1 mm for the duration of the test.
Five samples or 10 min (whichever is longer) after the first reported road surface condition “Moist”, stop the
recording of the surface condition measurement.
Using a towel and a fan, clean and dry the surface of the sensor.
Repeat the test at a temperature of -5 °C, using a NaCl solution having a freezing temperature of 0 °C.
3.3.4.4 Wet
Ensure a proper connection of the sensor to be tested and the whole measurement chain.
Set the climatic chamber to a temperature of 5 °C. Dew point temperature shall be at least 1 °C below the air
temperature to avoid condensation. The temperatures of air and sensor shall be identical and stabilised.
Install the precision scale close to the sensor to be tested under the spreading device. The mass of liquid
applied over the surface of the plate of the scale is recorded and converted to liquid thickness. This value
serves as reference for the test.
Using a towel and a fan, clean and dry the surface of the sensor.
Start the recording of the surface condition measurements.
Apply a water film thickness of 0,14 mm over the sensor (equivalent to the EN 15518-3 requirement 0,2 mm
– 30 %) and bring this thickness by steps of 0,02 mm up to 0,26 mm (equivalent to the EN 15518-3
requirement 0,2 mm + 30 %), each step being longer than the time constant of the sensor to be tested. The
last water film thickness has to remain constant for 6 min, or until the road surface condition measurement
shows “Wet”, whichever is first.
Then, enough water shall be applied as needed to keep the water film thickness between 0,26 mm and 1 mm
for the duration of the test.
Five samples or 10 min (whichever is longer) after the application of the water layer which generated the road
surface condition “Wet”, stop the recording of the surface condition measurement.
Using a towel and a fan, clean and dry the surface of the sensor.
Repeat the test at a temperature of -5 °C, using a NaCl solution having a freezing temperature of
-10 °C.
3.3.4.5 Streaming water
Ensure a proper connection of the sensor to be tested and the whole measurement chain.
Set the climatic chamber to a temperature of 5 °C. Dew point temperature shall be at least 1 °C below the air
temperature to avoid condensation. The temperatures of air and sensor shall be identical and stabilised.
Install the precision scale close to the sensor to be tested under the spreading device. The mass of liquid
applied over the surface of the plate of the scale is recorded and converted to liquid thickness. This value
serves as reference for the test.
Using a towel and a fan, clean and dry the surface of the sensor.
Start the recording of the surface condition measurements.
Apply a water film thickness of 1,4 mm over the sensor (equivalent to the EN 15518-3 requirement 2 mm
– 30 %) and bring this thickness by steps of 0,4 mm to 2,6 mm (equivalent to the EN 15518-3 requirement
2 mm + 30 %), each step being longer than the time constant of the sensor to be tested. The last water film
thickness has to remain constant for 6 min, or until the road surface condition measurement shows “Streaming
water”, whichever is first.
Then, enough water shall be applied as needed to keep the water film thickness above 2,6 mm for the
duration of the test.
Five samples or 10 min (whichever is longer) after the application of the water layer which generated the road
surface condition “Streaming water”, stop the recording of the surface condition measurement.
3.3.4.6 Slippery
 Phase one:
Ensure a proper connection of the sensor to be tested and the whole measurement chain.
Set the climatic chamber to a temperature of 5 °C. Dew point temperature shall be at least 1 °C below the air
temperature to avoid condensation. The temperatures of air and sensor shall be identical and stabilised.
Install the precision scale close to the sensor to be tested under the spreading device. The mass of liquid
applied over the surface of the plate of the scale is recorded and converted to liquid thickness. This value
serves as reference for the test.
Using a towel and a fan, clean and dry the surface of the sensor.
Start the recording of the surface condition measurements.
Apply a liquid film thickness of 0,5 mm over the sensor using a NaCl solution having a freezing temperature of
-5 °C. This liquid film thickness has to remain constant throughout the duration of the test.
Bring the temperature of the climatic chamber at a rate of 10 °C/hour to -10 °C.
Stop the recording.
Using a towel and a fan, clean and dry the surface of the sensor.
 Phase two:
Ensure a proper connection of the sensor to be tested and the whole measurement chain.
Set the climatic chamber to a temperature of -5 °C. Dew point temperature shall be at least 1 °C below the air
temperature to avoid condensation. The temperatures of air and sensor shall be identical and stabilised.
Install the precision scale close to the sensor to be tested. The mass of hoarfrost created over the surface of
the plate of the scale is recorded and converted to g/m . This value serves as reference for the test.
Using a towel and a fan, clean and dry the surface of the sensor.
Start the recording of the surface condition measurements.
Increase relative humidity up to 100 %.
Record the time at which hoarfrost is visually detected over the sensor. A minimum quantity of 20 g/m shall
be recorded by the precision scale.
Five samples or 10 min (whichever is longer) after the first reported road surface condition “Slippery”, stop the
recording of the surface condition measurement.
3.3.5 Result analysis
3.3.5.1 Dry
The test is successful if both following conditions are met:
 a first “Dry” road surface condition has been recorded within 6 min after the start of the test;
 the “Dry” road surface condition has then remained unchanged throughout the duration of the test.
3.3.5.2 Moist
The test is successful if both following conditions are met:
 a first “Moist” road surface condition has been recorded within 6 min after the initial application of the
liquid film thickness;
 the “Moist” road surface condition has then remained unchanged throughout the duration of the test.
3.3.5.3 Wet
The test is successful if both following conditions
...