EN 60068-2-18:2001

SLOVENSKI STANDARD
01-maj-2002
Environmental testing - Part 2-18: Tests - Tests R and guidance: Water
Environmental testing -- Part 2-18: Tests - Tests R and guidance: Water
Umweltprüfungen -- Teil 2-18: Prüfungen, Prüfung R und Leitfaden: Wasser
Essais d'environnement -- Partie 2-18: Essais - Essais R et guide: Eau
Ta slovenski standard je istoveten z: EN 60068-2-18:2001
ICS:
19.040 Preskušanje v zvezi z Environmental testing
okoljem
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 60068-2-18
NORME EUROPÉENNE
EUROPÄISCHE NORM January 2001
ICS 19.040
English version
Environmental testing
Part 2-18: Tests - Tests R and guidance: Water
(IEC 60068-2-18:2000)
Essais d'environnement Umweltprüfungen
Partie 2-18: Essais - Essais R et guide: Teil 2-18: Prüfungen, Prüfung R und
Eau Leitfaden: Wasser
(CEI 60068-2-18:2000) (IEC 60068-2-18:2000)
This European Standard was approved by CENELEC on 2000-11-01. CENELEC 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 Central Secretariat or to any CENELEC 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 CENELEC member into its own language and
notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic,
Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway,
Portugal, Spain, Sweden, Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2001 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60068-2-18:2001 E
Foreword
The text of document 104/170/FDIS, future edition 2 of IEC 60068-2-18, prepared by IEC TC 104,
Environmental conditions, classification and methods of test, was submitted to the IEC-CENELEC
parallel vote and was approved by CENELEC as EN 60068-2-18 on 2000-11-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2001-08-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2003-11-01
Annexes designated "normative" are part of the body of the standard.
Annexes designated "informative" are given for information only.
In this standard, annex ZA is normative and annexes A, B, C, D and E are informative.
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60068-2-18:2001 was approved by CENELEC as a
European Standard without any modification.
__________
- 3 - EN 60068-2-18:2001
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of
any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
IEC 60529 1989 Degrees of protection provided by EN 60529 1991
enclosures (IP Code) + corr. Mai 1993

NORME CEI
INTERNATIONALE
IEC
60068-2-18
INTERNATIONAL
Deuxième édition
STANDARD
Second edition
2000-10
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Essais d’environnement –
Partie 2-18:
Essais – Essai R et guide: Eau

Environmental testing –
Part 2-18:
Tests – Test R and guidance: Water

CODE PRIX
W
Commission Electrotechnique Internationale
PRICE CODE
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue
Pour prix, voir catalogue en vigueur

60068-2-18  IEC:2000 – 3 –
CONTENTS
Page
FOREWORD . 5
INTRODUCTION .7
Clause
1 Scope and object . 9
2 Normative references . 9
3 Definitions. 9
4 Survey of water tests. 11
4.1 General. 11
4.2 Description of Tests R: Water . 11
5 Test Ra: Falling drops . 13
5.1 Object. 13
5.2 Method Ra 1: Artificial rain . 13
5.3 Method Ra 2: Drip box . 19
6 Test Rb: Impacting water. 23
6.1 Object. 23
6.2 Method Rb 1: Oscillating tube and spray nozzle . 25
6.3 Method Rb 2: Water jet . 35
7 Test Rc: Immersion . 41
7.1 Object. 41
7.2 Method Rc 1: Water tank. 41
7.3 Method Rc 2: Pressurized water chamber. 45
Annex A (informative) Water characteristics to be considered when writing
the relevant specification .49
Annex B (informative) General guidance. 53
Annex C (informative) Guidance for Test Ra . 55
Annex D (informative) Guidance for Test Rb . 63
Annex E (informative) Guidance for Test Rc . 75
Figure 1 – Structuring of test methods and equivalence with the IP Code of IEC 60529 . 13
Figure 2 – Test Ra, definitions of angles and axes . 17
Figure C.1 – Test Ra 1, test apparatus and measurement set-up for drop sizes and
intensity for artificial rain method . 59
Figure C.2 – Test Ra 2, recommended test apparatus for the drip box method . 61
Figure D.1 – Test Rb 1.1, recommended test apparatus for the oscillating tube method. 67
Figure D.2 – Distribution of mean value of precipitation intensity in the oscillating tube area
for the above-specified measurement conditions. 69
Figure D.3 – Test Rb 1.2, recommended test apparatus for the spray nozzle method. 71
Figure D.4 – Standard test nozzle for the water jet method (hose nozzle) . 73

60068-2-18 © IEC:2000 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ENVIRONMENTAL TESTING –
Part 2-18: Tests – Test R and guidance: Water

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes International Standards. Their preparation is
entrusted to technical committees; any IEC National Committee interested in the subject dealt with may
participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization
for Standardization (ISO) in accordance with conditions determined by agreement between the two
organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60068-2-18 has been prepared by IEC technical committee 104:
Environmental conditions, classification and methods of test.
This second edition cancels and replaces the first edition published in 1989 and its
amendment 1 (1993). This second edition constitutes a technical revision.
It has the status of a basic safety publication in accordance with IEC Guide 104.
The text of this standard is based on the following documents:
FDIS Report on voting
104/170/FDIS 104/176/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 3.
Annexes A, B, C, D and E are for information only.
The committee has decided that the contents of this publication will remain unchanged until 2012.
At this date, the publication will be:
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
60068-2-18  IEC:2000 – 7 –
INTRODUCTION
1)
It is the intention of this part of IEC 60068 to fulfil the function of a basic publication by
making water tests available to product committees.
A number of water tests are described in other IEC publications. Some of them are well
established, for example, the test for classification of the second characteristic numeral of the
IP Code, clause 4 of IEC 60529.
This standard incorporates the majority of the most widely used tests, as well as making
available further methods and increasing the number of severities.
________
1)
IEC Guide 108:1994, The relationship between technical committees with horizontal functions and product
committees and the use of basic publications

60068-2-18  IEC:2000 – 9 –
ENVIRONMENTAL TESTING –
Part 2-18: Tests – Test R and guidance: Water
1 Scope and object
This part of IEC 60068 provides methods of test applicable to products which, during
transportation, storage or in service, may be subjected to falling drops, impacting water or
immersion. The primary purpose of water tests is to verify the ability of enclosures, covers and
seals to maintain components and equipment in good working order after and, when
necessary, under a standardized dropfield or immersion in water.
These tests are not corrosion tests and should not be considered and used as such.
The effects of a large temperature difference between the water and the specimen, such as
increased water ingress resulting from pressure changes, as well as thermal shock, are not
simulated.
Established water tests in other standards are not intended to simulate natural rainfall and their
quoted intensities are too high to be adopted for that purpose. Therefore, in addition to the
high-intensity severities, Test R includes an artificial rain test based upon natural conditions but
not taking into account high wind speeds generally associated with natural rain.
Guidance is given on the applicability of the tests and the severities to be selected.
2 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 60068. For dated references, subsequent amendments
to, or revisions of, these publications do not apply. However, parties to agreements based on
this part of IEC 60068 are encouraged to investigate the possibility of applying the most recent
edition of the normative documents indicated below. For undated references, the latest edition
of the normative documents referred to applies. Members of IEC and ISO maintain registers of
currently valid International Standards
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)
3 Definitions
For the purposes of this part of IEC 60068, the following definitions apply.
3.1
rain
precipitation in the form of waterdrops. Both the amount that falls and the actual falling action
of the waterdrops are often called rainfall

60068-2-18  IEC:2000 – 11 –
3.2
drizzle
precipitation in the form of very small, numerous and uniformly dispersed waterdrops that may
appear to float while following air currents
3.3
raindrop
drop of water having a diameter greater than 0,5 mm falling through the atmosphere
3.4
drizzledrop
drop of water having a diameter of 0,2 mm to 0,5 mm falling through the atmosphere
3.5
rainfall or drizzle intensity (R)
amount that falls per unit of time. Rainfall intensity (R) is given in millimetres per hour (mm/h)
where 1 l/(m .h) equals 1 mm/h
3.6
median volume diameter (D )
diameter of a drop whose size is such that 50 % of the volume of water reaching the ground is
comprised of smaller (or larger) drops:
0,19
D = 1,21 R (mm)
where R is the rainfall intensity, see above
4 Survey of water tests
4.1 General
This survey indicates the general structure of the various tests included in this standard.
The structuring of the different tests is given in figure 1.
4.2 Description of Tests R: Water
The water tests are structured into three groups.
– Ra: "Falling drops" which, in principle, is a test with artificial rain and a test simulating
falling drops from condensation or leakage.
– Rb: "Impacting water" where water jets impinge upon the test specimen with a certain force
and may assume any angle towards the test specimen.
– Rc: "Immersion" where the test specimen is immersed in water to specified depths or
equivalent pressures.
60068-2-18  IEC:2000 – 13 –
Water tests
R
Falling drops Impacting water Immersion
Ra Rb Rc
Method Rb 1 Method Rc 1
Method Ra 1
– Method Rb 1.1 Water tank
Artificial rain
Oscillating tube IPX7
IPX3 and IPX4
or
– Method Rb 1.2
Spray nozzle
(Hand-held shower)
IPX3 and IPX4
Method Rc 2
Method Ra 2 Method Rb 2
Pressurized water
Drip box Water jet
chamber
IPX1 and IPX2 IPX5 and IPX6
IEC  206/2000
Figure 1 – Structuring of test methods and equivalence with the IP Code of IEC 60529
5 Test Ra: Falling drops
5.1 Object
This test is applicable to products which, during transportation, storage or in service may be
exposed to vertical falling drops, the origin of these being, for example, natural rain, seepage
or condensation. It shall be clearly stated in the relevant specification whether a product
hereinafter referred to as a specimen has to function during testing or merely to survive
conditions of falling drops. In either case, the relevant specification shall always prescribe the
acceptable tolerances in performance.
5.2 Method Ra 1: Artificial rain
5.2.1 General description of the test
The test specimen is mounted on an appropriate fixture or base support. It is then subjected to
falling waterdrops, which simulate natural rain.
The basic requirements for the test apparatus are:
– Drop-generating nozzle or nozzles (see C.2.1 and figure C.1).
– Fixture for the specimen
The fixture shall simulate as far as possible the mounting of the specimen when in service;
for example, for wall-mounted equipment the fixture shall simulate a wall.

60068-2-18  IEC:2000 – 15 –
– Support of the test specimen
The support shall have a base area which is smaller than the base area of the specimen.
The support shall be either a turntable which has a rotation speed of 1 r/min and the
eccentricity (distance between turntable axis and specimen axis) is approximately 100 mm,
or a table which does not turn. The support shall be able to hold the specimen in any test
position and, if necessary, be tilted to a maximum of 90° from the vertical plane.
– Water supply with controls
The water used for the test shall be fresh tap water of good quality. In order to avoid
clogging of the nozzles, the water shall be filtered and may be demineralized. Details of the
characteristics of the water are given in annex A. During the test, the water temperature
shall not differ by more than 5 K from the temperature of the specimen under test. If the
water temperature is more than 5 K below the temperature of the specimen, a pressure
balance shall be provided for the specimen.
5.2.2 Severities
The severities, as indicated by intensity (and associated drop-size distribution), duration and tilt
angle of specimen shall be prescribed in the relevant specification. The values shall be
selected from those given below. Wind-driven rain is not simulated by this test as the wind
velocity is not a parameter of test.
– Intensity, mm/h and (associated drop-size distribution, mm):
10 ± 5 (D = 1,9 ± 0,2);  100 ± 20 (D = 2,9 ± 0,3);  400 ± 50 (D = 3,8 ± 0,4).
50 50 50
– Duration, minutes:
10, 30, 60, 120
– Tilt angle α, degrees:
0, 15, 30, 60, 90
NOTE The relevant specification may prescribe a longer duration.
5.2.3 Preconditioning
Preconditioning of the specimen and seals shall be carried out if prescribed in the relevant
specification.
5.2.4 Initial measurements
The specimen shall be submitted to the visual, dimensional and functional checks prescribed
by the relevant specification. All features of the specimen likely to affect the test result, for
example surface treatment, enclosures, covers or seals, shall be inspected to ensure that the
instructions of the relevant specification have been followed.
5.2.5 Testing
The specimen shall be mounted on the support either
– in its normal operating position, as prescribed in the relevant specification; or
– tilted from the normal operating position and provision made for rotating the specimen in a
plane perpendicular to the tilted axis. The rotation may be achieved by a rotating support
table or by repositioning the specimen at regular intervals during the test. Alternatively, the
specimen can be oscillated through an arc of 270° to avoid the need for slip-ring contacts.

60068-2-18  IEC:2000 – 17 –
The relevant specification shall specify the tilt angle or angles, the face or faces to be exposed
to the drop field and the duration of exposure for each side, or whether the specimen shall be
continuously rotated or oscillated through 270°. See also figure 2.
The specimen shall be subjected to artificial rain with severities selected from 5.2.2 and
prescribed by the relevant specification.
The relevant specification shall state whether the specimen shall be operated during testing
and if intermediate measurements shall be made.
Appropriate safety precautions shall be taken when testing the specimen in the energized
condition.
5.2.6 Recovery
Unless otherwise required in the relevant specification, the specimen shall be thoroughly dried
externally by wiping or by applying low-velocity forced air at room temperature.
Tilt angle
Gimballed and rotatable
table
IEC  207/2000
Figure 2 – Test Ra, definitions of angles and axes
5.2.7 Final measurements
The specimen shall be examined for ingress of water and submitted to visual, dimensional and
functional checks prescribed by the relevant specification.
Any ingress of water should be quantified if possible and reported.

60068-2-18  IEC:2000 – 19 –
5.2.8 Information to be given in the relevant specification
Where this test is included in the relevant specification, the following details shall be given in
so far as they are applicable. The relevant specification shall supply information as required in
the clauses listed below, paying particular attention to the items marked with an asterisk (*) as
this information is always required.
Subclause
a) Severities* 5.2.2
b) Preconditioning 5.2.3
c) Initial measurements* 5.2.4
d) Mounting of specimen* 5.2.5
e) Specimen position or positions during testing* 5.2.5
f) State of the specimen during testing* 5.2.5
g) Intermediate measurements 5.2.5
h) Recovery 5.2.6
i) Final measurements* 5.2.7
5.3 Method Ra 2: Drip box
5.3.1 General description of the test
The test specimen is mounted on an appropriate fixture placed under the drip box. The test
specimen is subjected to water drops, which simulate water falling as a result of condensation
or leakage.
The basic requirements for the test apparatus are:
– Drip box
The drip box shall normally have a base area larger than the projected area of the
specimen. If the base of the drip box is smaller than that of the specimen under test, the
latter may be divided into several sections, the area of each section being large enough to
be covered by the dripping water. The test is continued until the whole area of the specimen
has been sprinkled for the specified time. The drip box shall be capable of providing a
uniform dropfield with a precipitation of the specified intensity.
The grid pattern of the nozzles shall be 20 mm (for IP Code tests) or 25 mm. The distance
from the bottom of the drip box to the highest point of the specimen shall be adjustable to
either 0,2 m or 2 m. A suitable drip-box layout is described in C.2.2 and figure C.2.
– Fixture for the specimen
The fixture shall simulate as far as possible the mounting of the specimen when in service;
for example, for wall-mounted equipment the fixture shall simulate a wall.
– Support of the test specimen
The support shall have a base area which is smaller than the base area of the specimen.
The support shall either be a turntable which has a rotation speed of 1 r/min and the
eccentricity (distance between turntable axis and specimen axis) is approximately 100 mm,
or a table which does not turn. The support shall be able to hold the specimen in any test
position and, if necessary, be tilted to a maximum of 45° from the vertical plane.

60068-2-18  IEC:2000 – 21 –
– Water supply with controls
The water used for the test shall be fresh tap water of good quality. In order to avoid
clogging of the nozzles, the water shall be filtered and may be demineralized. Details of the
characteristics of the water are given in annex A. During the test, the water temperature
shall not differ by more than 5 K from the temperature of the specimen under test. If the
water temperature is more than 5 K below the temperature of the specimen, a pressure
balance shall be provided for the specimen.
5.3.2 Severities
The severities, as indicated by drop falling height, tilt angle of specimen, duration and water
intensity, shall be prescribed in the relevant specification. The values shall be selected from
the following:
– Drop falling height, (h), m: 0,2; 2
– Tilt angle α, degrees: 0; 15; 30; 45
– Duration, minutes: 3; 10; 30; 60
NOTE The 3 min duration applies only when a tilt angle of 0° is specified.
+30 +30
– Water intensity, mm/h: 60 ; 180
−0 −0
5.3.3 Preconditioning
Preconditioning of the specimen and seals shall be carried out if prescribed in the relevant
specification.
5.3.4 Initial measurements
The specimen shall be submitted to the visual, dimensional and functional checks prescribed
by the relevant specification. All the features of the specimen likely to affect the test result, for
example, surface treatment, covers or seals, shall be inspected to ensure that the instructions
of the relevant specification have been followed.
5.3.5 Testing
The specimen shall be mounted on the support in its normal operating position under the drip
box. The support shall then either be rotated or tilted to the specified angle in each of the four
positions of tilt. These positions are on either side of the vertical in two mutually perpendicular
planes. If a special mounting condition is required (for example, wall or ceiling), it shall be
prescribed by the relevant specification.
In both cases, the test shall be carried out in the conditions specified in 5.3.1 and severity
selected from 5.3.2.
In the case of tilted support, the duration shall be divided equally between the four positions.
The relevant specification shall state whether the specimen shall be operated during testing
and if intermediate measurements shall be made. Appropriate safety precautions shall be
taken when testing the specimen in the energized condition.

60068-2-18  IEC:2000 – 23 –
5.3.6 Recovery
Unless otherwise required in the relevant specification, the specimen shall be thoroughly dried
externally by wiping or by applying low-velocity forced air at room temperature.
5.3.7 Final measurements
The specimen shall be examined for ingress of water and submitted to visual, dimensional and
functional checks prescribed by the relevant specification.
Any ingress of water should be quantified if possible and reported.
5.3.8 Information to be given in the relevant specification
Where this test is included in the relevant specification, the following details shall be given in
so far as they are applicable. The relevant specification shall supply information as required
in the clauses listed below, paying particular attention to the items marked with an asterisk (*)
as this information is always required.
Subclause
a) Severities* 5.3.2
b) Preconditioning 5.3.3
c) Initial measurements* 5.3.4
d) Mounting of specimen* 5.3.5
e) Specimen position or positions during testing* 5.3.5
f) State of the specimen during testing* 5.3.5
g) Intermediate measurements 5.3.5
h) Recovery 5.3.6
i) Final measurements* 5.3.7
6 Test Rb: Impacting water
6.1 Object
This test is applicable to products which, during transportation, storage or in service may be
subjected to impacting water. The origin for this can be water from cloudbursts, heavy driving
rain, sprinkler systems, spray from wheels, sluicing or breaking seas. The relevant
specification should clearly prescribe whether a product tested separately, hereinafter referred
to as a specimen, has to function during testing or merely survive conditions of impacting
water. In either case, the relevant specification shall always prescribe the acceptable
tolerances in performance.
60068-2-18  IEC:2000 – 25 –
6.2 Method Rb 1: Oscillating tube and spray nozzle
6.2.1 General description of the test
The tests are intended to simulate spraying or splashing water, for example, the results of
water action of sprinkler systems. Guidance for this test is given in annex D. The test is made
using either the test device described in figure D.1 or the test device described in figure D.3 in
accordance with the relevant specification. The test specimen is mounted on an appropriate
fixture and is subjected to impacting water generated from either a semicircular tube or a spray
nozzle.
6.2.2 Method Rb 1.1: Oscillating tube
6.2.2.1 Test apparatus
The basic requirements for the test apparatus are:
– Oscillating tubes
Three types of tube may be used. The tube shall be provided with nozzles of either 0,4 mm
diameter for Type 1 and Type 2 or 0,8 mm diameter for Type 3, at a 50 mm centre-
to-centre distance over an arc of 60° on either side of the vertical for Type 1 or 90° on
either side of the vertical for Type 2 and Type 3. The tube shall be able to oscillate through
an angle of 60° on either side of the vertical for Type 1 or 180° on either side of the vertical
for Type 2 and Type 3.
The maximum acceptable radius of the oscillating tubes, Type 1 and Type 2 is 1 600 mm.
For oscillating tube Type 3, the radius shall not exceed 800 mm. The radius shall be
selected in such a way that the clearance between the specimen and the inside of the tube
does not exceed 200 mm.
The relationship between the number of nozzles, each having a mean flow rate of 0,07 l/min
or 0,6 l/min and the total flow rate is given in table 2.
A suitable apparatus is shown in figure D.1.
– Fixture for the specimen
The fixture shall simulate as far as possible the mounting structure to be used in the real
use of products, for example, for wall-mounted equipment the fixture shall simulate a wall.
– Support for the specimen
The support for the specimen shall not be perforated for Type 1 and shall be suitably
perforated for Type 2 and Type 3.
– Water supply with controls
The water used for the test shall be fresh tap water of good quality. In order to avoid
clogging of the nozzles, the water shall be filtered and may be demineralized. Details of the
characteristics of the water are given in annex A. During the test, the water temperature
shall not differ by more than 5 K from the temperature of the specimen under test. If the
water temperature is more than 5 K below the temperature of the specimen, a pressure
balance shall be provided for the specimen.
6.2.2.2 Severities
The severities as indicated by the nozzle angle, water flow rate per hole, tube oscillating angle
and duration shall be prescribed in the relevant specification. The values shall be selected from
those given below.
Any combination of water test severities can be chosen independently. In this case, such a
combination shall be stated in the relevant specification.

60068-2-18  IEC:2000 – 27 –
Type 1 Tube
– Nozzle angle α, degrees ±60
– Water flow per hole, l/min 0,07 ± 5 %
– Tube oscillating angle β,degrees ±60
– Duration, min 2 × 5
Type 2 Tube
– Nozzle angle α, degrees ±90
– Water flow per hole, l/min 0,07 ± 5 %
– Tube oscillating angle, β degrees ±180 (approximately)
– Duration, min 10, 30, 60
Type 3 Tube
– Nozzle angle α, degrees ±90
– Water flow per hole, l/min 0,6 ± 0,03
– Tube oscillating angle, β degrees ±180 (approximately)
– Duration, min 2 × 5
In some cases, the relevant specification may prescribe a longer duration.
6.2.2.3 Preconditioning
Preconditioning of the specimen and seals shall be carried out if prescribed in the relevant
specification.
6.2.2.4 Initial measurements
The specimen shall be submitted to the visual, dimensional and functional checks prescribed
by the relevant specification. All features of the specimen likely to affect the test results, such
as surface treatment, covers or sealings, shall be inspected to ensure that the instructions of
the relevant specification have been followed.
6.2.2.5 Testing
Three types are described:
Type 1:
The specimen to be tested shall be attached to a fixture, if specified, and shall be placed on
the support in its normal operational attitude. For this test, the support shall not be perforated.
An oscillating tube as described in figure D.1, with nozzles over an arc of 60° on either side of
vertical shall be chosen having a radius to meet the dimensional requirements of the test
specimen. The maximum radius is 1 600 mm. If the test specimen is too large, the spray
nozzle test shall be used. The tube is caused to oscillate through an angle of 60° on either side

of vertical. The time taken for one complete oscillation +60° to –60° to +60° shall be
approximately 4 s.
Water flow shall be set to the required rate given in table 2.

60068-2-18  IEC:2000 – 29 –
The duration of the test shall be 5 min.
The test specimen shall be turned through a horizontal angle of 90° and the test shall be
continued for a further 5 min.
If it is not possible to wet all parts of the test specimen, the support shall be moved up and
down or the spray nozzle test shall be used.
The relevant specification shall state whether the specimen shall be operated during test and if
intermediate measurements shall be made.
Appropriate safety precautions shall be taken when testing in the energized condition.
Table 2 – Oscillating tube – Relationship of number of nozzles
and total water flow to tube radius
Type 1Type 2Type 3
Number Number Number
Tube Total Total Total
of open of open of open
radius R water flow water flow water flow
nozzles nozzles nozzles
1) 1) 1)
mm l/min l/min l/min
N N N
200 8 0,56 12 0,84 12 7,2
400 16 1,1 25 1,8 25 15
600 25 1,8 37 2,6 37 22,2
800 33 2,3 50 3,5 50 30
1 000 41 2,9 62 4,3 ––
1 200 50 3,5 75 5,3 ––
1 400 58 4,1 87 6,1 ––
1 600 67 4,7 100 7 ––
1)
Depending on the actual arrangement of nozzle centres at the specified distance, the number
of open nozzles N may be increased by 1.
Type 2:
The test is the same as for Type 1 with the following differences:
– the support shall be perforated unless prescribed otherwise in the relevant specification;
– the oscillating tube shall have nozzles over an arc of 90° on either side of vertical;
– the tube shall oscillate through an angle of almost 360°, 180° on either side of vertical;
– the time taken for one complete oscillation, +180° to –180° to +180° shall be approximately
12 s;
– the test duration shall be selected from 6.2.2.2;
– the test specimen is not turned through a horizontal angle of 90° and the test is not
continued for any further time.
NOTE If orientation affects the severity of the test, the relevant specification shall prescribe it.
The relevant specification shall state whether the specimen shall be operated during testing
and if intermediate measurements shall be made.

60068-2-18  IEC:2000 – 31 –
Appropriate safety precautions shall be taken when testing in the energized condition.
Type 3:
The test is the same as for Type 2 with the following differences:
– the test duration is 2 × 5 min; that is after 5 min of test, the specimen is turned through a
horizontal angle of 90° and the test is continued for a further 5 min.
The relevant specification shall state whether the specimen shall be operated during testing
and if intermediate measurements shall be made.
Appropriate safety precautions shall be taken when testing in the energized condition.
6.2.2.6 Recovery
Unless otherwise required in the relevant specification, the specimen shall be thoroughly dried
externally by wiping or by applying low-velocity forced air at room temperature.
6.2.2.7 Final measurements
The specimen shall be examined for ingress of water, and submitted to the visual, dimensional
and functional checks prescribed by the relevant specification.
Any ingress of water shall be quantified if possible and reported.
6.2.2.8 Information to be given in the relevant specification
Where this test is included in the relevant specification, the following details shall be given in
so far as they are applicable. The relevant specification shall supply information as required
in the clauses listed below, paying particular attention to the items marked with an asterisk (*)
as this information is always required.
Subclause
a) Severities* 6.2.2.2
b) Preconditioning 6.2.2.3
c) Initial measurements* 6.2.2.4
d) Mounting of specimen* 6.2.2.5
e) Specimen position or positions during testing* 6.2.2.5
f) State of the specimen during testing* 6.2.2.5
g) Intermediate measurements 6.2.2.5
h) Recovery 6.2.2.6
i) Final measurements* 6.2.2.7

60068-2-18  IEC:2000 – 33 –
6.2.3 Method Rb 1.2: Spray nozzle
6.2.3.1 Test apparatus
The basic requirements for the test apparatus are:
– Spray nozzle (also known as hand-held shower)
A spray nozzle with a spray cone of 78° and a moving shield which is able to limit the upper
part of the spray cone to 30° from the horizontal. The shield may be removed as specified.
The spray nozzle shall have a delivery rate of 10 l/min ± 5 % which necessitates a water
pressure of 50 kPa to 150 kPa (0,5 bar to 1,5 bar) (see figure D.3).
– Fixture for the specimen
The fixture shall simulate as far as possible the mounting structure to be used in real use of
products, for example, for wall-mounted equipment the fixture shall simulate a wall.
– Support for the specimen
The support for the specimen shall have a base area which is smaller than the base area of
the specimen or be suitably perforated.
– Water supply with controls
The water supply shall be capable of delivering, in a stable flow, at least 10 l/min. The
water used for the test shall be fresh tap water of good quality. In order to avoid clogging of
the holes, the water shall be filtered and may be demineralized. Details of the
characteristics of the water are given in annex A. During the test, the water temperature
shall not differ by more than 5 K from the temperature of the specimen under test. If the
water temperature is more than 5 K below the temperature of the specimen, a pressure
balance shall be provided for the specimen.
6.2.3.2 Severities
The specimen surfaces to be sprayed, if not all, shall be specified. The severities as indicated
by the use of the shield or not and the test duration shall be prescribed in the relevant
specification. The severities shall be selected from those given below.
– Moving shield: in use,
removed.
– Test duration, min/m test surface, calculated with a tolerance of ±10 % (subject to a
minimum duration, min)
1 (5); 3 (15); 6 (30).
In some cases, the relevant specification may prescribe a longer duration.
6.2.3.3 Preconditioning
Preconditioning of the specimen and seals shall be carried out if prescribed in the relevant
specification.
6.2.3.4 Initial measurements
The specimen shall be submitted to the visual, dimensional and functional checks prescribed
by the relevant specification. All features of the specimen likely to affect the test result such as
surface treatment, covers or sealings shall be inspected to ensure that the instructions of the
relevant specification have been followed.

60068-2-18  IEC:2000 – 35 –
6.2.3.5 Testing
The specimen shall be mounted as described in the oscillating tube test procedure (6.2.2.5
Type 1 or Type 2). The water pressure shall be adjusted to give a delivery rate of 10 l/min ± 5 %.
It shall be kept constant throughout the test. The specified surfaces shall be sprayed for the
specified duration and from a distance of (0,4 ± 0,1) m. When the spray nozzle is used as an
alternative to the oscillating tube Type 2, the moving shield shall be removed and the spray shall
be applied at ±180° from vertical.
The relevant specification shall state whether the specimen shall be operated during testing
and if intermediate measurements shall be made.
Appropriate safety precautions shall be taken when testing in the energized condition.
6.2.3.6 Recovery
Unless otherwise required in the relevant specification, the specimen shall be thoroughly dried
externally by wiping or by applying low-velocity forced air at room temperature.
6.2.3.7 Final measurements
The specimen shall be examined for ingress of water, and submitted to the visual, dimensional
and functional checks prescribed by the relevant specification.
Any ingress of water shall be quantified if possible and reported.
6.2.3.8 Information to be given in the relevant specification
Where this test is included in the relevant specification, the following details shall be given in
so far as they are applicable. The relevant specification shall supply information as required in
the clauses listed below, paying particular attention to the items marked with an asterisk (*) as
this information is always required.
Subclause
a) Severities* 6.2.3.2
b) Preconditioning 6.2.3 3
c) Initial measurements* 6.2.3.4
d) Mounting of specimen* 6.2.3.5
e) Specimen position or positions during testing* 6.2.3.5
f) State of the specimen during testing* 6.2.3.5
g) Intermediate measurements 6.2.3.5
h) Recovery 6.2.3.6
i) Final measurements* 6.2.3.7
6.3 Method Rb 2: Water jet
6.3.1 General description of the test
The test specimen is mounted on a fixture. The test specimen is subjected to a water jet which
should simulate wheel spray, or breaking seas. The standard test nozzle is described in D.2.2
and figure D.4.
60068-2-18  IEC:2000 – 37 –
The basic requirements for the test apparatus are:
– Hose nozzle
The hose nozzle shall give a solid water jet and have a free diameter of 6,3 mm and
12,5 mm for the small and large nozzle respectively (see figure D.4).
– Fixture for the specimen
The fixture shall simulate as far as possible the mounting structure to be used in the real
use of products, for example, for wall-mounted equipment the fixture shall simulate a wall.
The fixture for the specimen shall have a base area which is smaller than the base area of
the specimen or be suitably perforated.
The fixture must have a sufficient strength and stability to withstand the hydrodynamic
effect of the water jet.
– Water supply
...