ISO 19880-5:2019

INTERNATIONAL ISO
STANDARD 19880-5
First edition
2019-11
Gaseous hydrogen — Fuelling
stations —
Part 5:
Dispenser hoses and hose assemblies
Reference number
©
ISO 2019
© ISO 2019
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Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 3
4 Classification . 5
5 Materials and construction . 6
5.1 General . 6
5.2 Lining . 6
5.3 Reinforcement . 6
5.4 Cover . 6
5.5 Static electricity dissipation . 6
5.5.1 General. 6
5.5.2 External surface . 6
5.5.3 Internal surface . 6
6 Dimensions and tolerances . 7
7 Performance requirements and testing . 7
7.1 General . 7
7.2 Leakage test . 7
7.2.1 General. 7
7.2.2 Method A . 7
7.2.3 Method B . 8
7.3 Hydrostatic strength . 8
7.3.1 Proof pressure test . 8
7.3.2 Ultimate strength. 8
7.4 Electrical conductivity . 8
7.5 Tensile test of hose assembly . 9
7.5.1 General. 9
7.5.2 Test method . 9
7.6 Vertical load strength . 9
7.6.1 General. 9
7.6.2 Test method .10
7.7 Torsion strength . .10
7.7.1 General.10
7.7.2 Test method .11
7.8 Pressure cycle test (Hydraulic-pressure impulse test) .12
7.8.1 General.12
7.8.2 Apparatus .12
7.8.3 Test fluid .12
7.8.4 Test temperature .12
7.8.5 Test piece .12
7.8.6 Procedure .13
7.9 Hydrogen impulse test .14
7.10 Corrosion test .14
7.10.1 General.14
7.10.2 Test conditions.14
7.11 Minimum bend radius .15
7.12 Hose permeation .15
7.12.1 General.15
7.12.2 Test Method A .15
7.12.3 Test Method B .16
7.13 Ozone resistance.16
7.14 Ultraviolet light and water exposure test . .16
7.14.1 Applicability and verification .16
7.14.2 Test conditions.16
7.14.3 Length of exposure . .16
7.15 Crush test .16
7.15.1 General.16
7.15.2 Test method .17
7.16 Abrasion resistance test .17
7.17 Marking material legibility .17
7.17.1 General.17
7.17.2 Test method .17
7.18 Electrical properties of lining material .17
7.18.1 General.17
7.18.2 Dielectric breakdown voltage .17
7.18.3 Volume resistivity .17
7.18.4 Criteria of electric properties of lining materials .18
8 Marking .18
8.1 General .18
8.2 Hose assemblies .18
8.3 Hose .19
8.4 Hose end fittings or couplings .19
9 Instruction manual .19
9.1 General .19
9.2 Selection.19
9.3 Installation .20
9.4 Inspection and maintenance .20
9.5 Safety precautions and usage .20
10 Test report .20
Annex A (normative) Type tests and routine tests .22
Annex B (informative) Production acceptance tests .23
Annex C (informative) Hydrogen impulse test .24
Bibliography .27
iv © ISO 2019 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by ISO/TC 197, Hydrogen technologies.
A list of all parts in the ISO 19880 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
Introduction
This document promotes the implementation of performance-based testing for components of
dispensing systems and fuelling stations that are based on proven engineering principles, research
and the combined expertise of gas utilities, fuel providers, manufacturers, users, and others having
specialized experience.
The successful commercialization of hydrogen vehicle technologies requires codes and standards
pertaining to fuelling stations, vehicle fuel system components, and the global homologation of standards
requirements for technologies with the same end use. Essentially this will allow manufacturers to
achieve economies of scale by producing one product for use globally.
International harmonization contributes to reducing technical barriers and stimulates related markets.
A series of documents that address hydrogen-fuelled vehicles and fuelling stations is being developed.
These documents will provide internationally homologized minimum safety performance criteria at
the component level, thus providing a foundation to build a safe “fuelling system”.
This document was developed using the standard ANSI/CSA HGV 4.2-2013.
This document was developed based on five pressure classes of wire or textile reinforced hoses and
hose assemblies suitable for use with gaseous hydrogen for hydrogen dispensing. This is based on
technologies in use at the time of the development of the requirements.
In the future, other types and classes of hoses and hose assemblies will need to be evaluated to
determine the suitability of requirements in this document.
This document applies to newly manufactured hoses and hose assemblies for connecting a dispenser to
a high pressure fuelling nozzle.
A nozzle vent hose is included in this document; however the pressure rating may be lower than the
nozzle rating, based on the nozzle and dispenser design.
For general hydrogen safety information, see ISO/TR 15916.
vi © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 19880-5:2019(E)
Gaseous hydrogen — Fuelling stations —
Part 5:
Dispenser hoses and hose assemblies
1 Scope
This document specifies the requirements for wire or textile reinforced hoses and hose assemblies
suitable for dispensing hydrogen up to 70 MPa nominal working pressure, in the operating temperature
range of −40 °C to 65 °C.
This document contains safety requirements for material, design, manufacture and testing of gaseous
hydrogen hose and hose assemblies for hydrogen fuelling stations.
Hoses and hose assemblies excluded from the scope of this document are the following:
1) those used as part of a vehicle high pressure on-board fuel storage system,
2) those used as part of a vehicle low pressure fuel delivery system, and
3) flexible metal hoses.
NOTE 1 This document was developed primarily for hoses and hose assemblies for dispensing high pressure
hydrogen from refuelling dispensers to hydrogen vehicles. Requirements for hoses used to deliver hydrogen
from a transportable vessel (e.g. trailer) into a buffer storage of a station are addressed in ISO 16964.
NOTE 2 Hose assemblies include the hose with connectors on each end (see Figure 1). Each connector has two
basic functional elements that are addressed as described below:
1) Coupling to hose. This function is defined by requirements and verified (along with the hose itself) by
performance-based tests in this document.
2) Fitting for transition and connection to the piping system or equipment. This function is addressed by
reference to appropriate hydrogen equipment standards and piping codes.
Key
1 hose assembly
2 mechanical joint
3 fitting
4 nipple
5 coupling
6 crimped socket
7 hose
Figure 1 — Hose assembly and fitting
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.
ISO 1402, Rubber and plastics hoses and hose assemblies — Hydrostatic testing
ISO 4671, Rubber and plastics hoses and hose assemblies — Methods of measurement of the dimensions of
hoses and the lengths of hose assemblies
ISO 4080:2009, Rubber and plastics hoses and hose assemblies — Determination of permeability to gas
ISO 6802, Rubber or plastics hoses and hose assemblies — Hydraulic impulse test with flexing
ISO 6803:2017, Rubber or plastics hoses and hose assemblies — Hydraulic-pressure impulse test
without flexing
ISO 7326:2016, Rubber and plastics hoses — Assessment of ozone resistance under static conditions
ISO 8031:2009, Rubber and plastics hoses and hose assemblies — Determination of electrical resistance
and conductivity
ISO 8330, Rubber and plastics hoses and hose assemblies — Vocabulary
ISO 8331, Rubber and plastics hoses and hose assemblies — Guidelines for selection, storage, use and
maintenance
ISO 9227, Corrosion tests in artificial atmospheres — Salt spray tests
2 © ISO 2019 – All rights reserved

ISO 15649, Petroleum and natural gas industries — Piping
ISO 16964, Gas cylinders — Flexible hoses assemblies — Specification and testing
ISO 17268, Gaseous hydrogen land vehicle refuelling connection devices
1)
ISO 19880-1 , Gaseous hydrogen — Fuelling stations — Part 1: General requirements
ISO 30013, Rubber and plastics hoses — Methods of exposure to laboratory light sources — Determination
of changes in colour, appearance and other physical properties
IEC 60243-1, Electric strength of insulating materials — Test methods — Part 1: Tests at power frequencies
IEC 62631-3-1, Dielectric and resistive properties of solid insulating materials — Part 3-1: Determination
of resistive properties (DC methods) — Volume resistance and volume resistivity — General method
3 Terms and definitions
For the purpose of this document, the terms and definitions given in ISO 8330, ISO 19880-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
connector
matching parts (such as male and female parts) that can be put together to form a "connection" which
permits the transfer of fluids, electric power, or control signals
Note 1 to entry: Fittings (3.4) are a type of connector used in piping systems.
Note 2 to entry: Examples of connectors commonly used in hydrogen systems are as follows:
a) The fuelling nozzle “connector” mates with the receptacle “connector” on the vehicle to form the connection
for transfer of compressed hydrogen between the dispenser and the vehicle, as defined in ISO 17268 for this
specific application.
b) The hose assemblies have connectors on each end that allow coupling (3.2) to the hoses and connection to
the piping system (e.g. hose breakaway device or fuelling nozzle).
c) Control systems often use electrical connectors to allow rapid and secure assembly or replacement.
3.2
coupling
integrated structure of nipple and socket with end portion of a hose crimped together as shown in
Figure 1
3.3
dispenser hose
fuelling hose
hose assembly (3.5) used for dispensing gaseous hydrogen to vehicles through a nozzle
Note 1 to entry: See Figure 2.
1) Under preparation.
Key
1 dispenser
2 hose breakaway device (ISO 19880-3)
3 fitting (3.4)
4 hose assembly (3.5)
5 connector (3.1)
6 nozzle (ISO 17268)
7 receptacle on vehicle (ISO 17268)
8 vehicle
Figure 2 — Components connecting a dispenser to a vehicle
3.4
fitting
connector (3.1) used to join any pressure retaining components in the system, and in the case of the
hose assembly (3.5), device, usually made of metal, attached to the end of a hose to facilitate connection
to equipment or other hose shown in Figure 1
Note 1 to entry: Fittings can be used in a finished hose assembly; however requirements for fittings are out of
scope of this document.
3.5
hose assembly
assembly which includes the hose and end connections, including any necessary fittings (3.4), bend
restrictors, and appropriate markings
3.6
nozzle vent hose
hose used to depressurize the fuelling nozzle and vent the hydrogen to an approved location
3.7
minimum bend radius
smallest specified radius to which a hose may be bent in service
Note 1 to entry: The minimum bend radius is shown in Table 3.
4 © ISO 2019 – All rights reserved

3.8
pressure rating
maximum pressure at which it is permissible to operate a component as specified by the manufacturer
at the maximum temperature expected during service
3.9
proof pressure
pressure applied during a non-destructive test and held for a specified period of time to prove the
integrity of the construction
4 Classification
This clause applies to newly manufactured hoses and hose assemblies for dispenser hoses connecting
the dispenser to the fuelling nozzle supply port.
Hoses and couplings shall meet the requirements in this document with end fittings selected by the
manufacturer, customer, or testing agency as required to connect to the test equipment. Fittings shall
be consistent with the requirements of the appropriate documents in the ISO 19880-series, ISO 17268,
or ISO 15649.
The end fitting of the hose assembly may be changed to another type that meets requirements defined
above without the need to repeat the performance tests for verification of the hose assembly and its
coupling as long as the hose coupling remains unchanged.
Some newly manufactured hoses and hose assemblies include vent lines required by some fuelling
nozzles. Nozzle vent hose assemblies shall meet the requirements of ISO 16964 or the requirements in
this document and be appropriately rated for operation in the vent system that has been defined based
on the nozzle manufacturer instructions and the dispenser design.
Table 1 converts Hydrogen Service Levels (HSL), as defined in ISO 19880-1, to pressure levels.
When using ISO 16964, the hose rating is 125 % of the working pressure which is 10 % lower than the
pressure ratings in Table 1.
A hose assembly shall be designated according to the pressure classes defined in Table 1 or by the
manufacturer’s stated pressure rating. The information in Table 1 is taken from ISO 19880-1 (and
pressure class H11 is added). The pressure rating of the hose assembly shall be equal to or above the
dispenser pressure ratings. For further information regarding the relationships between pressure
terms, see ISO 19880-1.
Table 1 — Hose assembly pressure levels and minimum pressure ratings
Maximum allowable
working pressure (MAWP)
Pressure level (HSL) Pressure class
(Minimum component pressure rating
for dispenser components)
(MPa) (MPa)
11 H11 15,13
25 H25 34,38
35 H35 48,13
50 H50 68,75
70 H70 96,25
The hoses and hose assemblies shall be designed to operate at temperatures ranging from −40 °C to 65 °C.
5 Materials and construction
5.1 General
The hose and liner shall be constructed with materials that are resistant to corrosion and exposure to
hydrogen.
5.2 Lining
The lining shall be of uniform thickness and free from defects. Defects are defined as but are not limited
to bubbles, thinning, gouging, or discoloration.
The lining may also consist of multiple material layers.
5.3 Reinforcement
The reinforcement consists of one or more layers of suitable wire or textile material applied by any
suitable technique.
5.4 Cover
The cover shall be resistant to abrasion, cracking, crazing, the effects of exposure to ultraviolet light
and ozone, be of uniform thickness, and free from defects. Defects may include but are not limited to
bubbles, thinning, gouging, or discoloration. All outer covering shall either be of a permeable material
or sufficiently perforated to avoid diffused gas build up.
5.5 Static electricity dissipation
5.5.1 General
Static electricity can be generated on the external and interior surface of a hose assembly.
5.5.2 External surface
The hose assembly shall be constructed so as to provide an external, electrically conductive, bonding
path between the end couplings to dissipate external static electric charges.
5.5.3 Internal surface
The hose assembly shall be constructed so that the liner provides an adequate internal layer of
prevention to avoid dielectric breakdown by static electricity in the fluid during normal use.
6 © ISO 2019 – All rights reserved

6 Dimensions and tolerances
When measured in accordance with ISO 4671, typical diameters and concentricity of hoses are given in
Table 2.
Table 2 — Typical diameters and concentricity of hoses
Inside diameter Concentricity
Maximum outside (Maximum variation in wall
mm
Nominal size
diameter of hose thickness between inside
minimum maximum diameter and outside diameter)
mm mm
6,3 5,9 7,0 25 0,8
8 7,7 8,5 30
1,0
10 9,3 10,1 35
7 Performance requirements and testing
7.1 General
Performance requirements shall be determined by the following tests and carried out by type tests,
routine tests and production acceptance tests.
Type tests are those required to confirm that a particular hose or hose assembly design, manufactured
by a particular method from particular materials, meets all the requirements of this document. The
tests shall be repeated whenever a change in the method of manufacture or materials used occurs.
They shall be performed on all sizes and types except those of the same size and construction.
Routine tests are those required to be carried out on each length of a finished hose or hose assembly
prior to dispatch.
Type tests and routine tests shall be carried out as specified in Annex A.
Production acceptance tests are those required to control the quality of the manufacturing. The
frequencies specified in Annex B are given as a guide only and determined by the manufacturer or
between the manufacturer and the customer or the certifying body.
7.2 Leakage test
7.2.1 General
Leakage tests shall be conducted in accordance with Method A for type tests and Method B for routine
tests. Method A is also recommended for production acceptance tests.
7.2.2 Method A
When tested in accordance with ISO 4080:2009, Method 3, with the following conditions, the hourly
leakage rate shall be less than 20 ml/h under normal pressure and temperature conditions.
The test can be done at room temperature. The amount shall be converted to 15 °C.
The test piece shall have a free length of 0,5 m between the couplings. Connect the test piece to the
hydrogen gas supply with a suitable connector and purge the test assembly with hydrogen gas. Adjust
the temperature of the water bath to the specified value.
Insert the test assembly into the transparent tube and immerse it in a water bath so that it is inclined at
approximately 20° to the horizontal.
Apply the gas pressure of 1,375 × HSL and maintain it for 10 min. This is the time necessary for releasing
trapped air in the reinforcement layer to the outside of the hose through perforated holes. Then, during
the next 5 min, collect the gas and measure the amount while maintaining the pressure. This amount is
converted to an amount per hour.
7.2.3 Method B
For this test a length of any assembly hose can be used. Hydrogen or helium can be used as test gas.
Connect the test piece to the test gas supply with a suitable connector and purge the test assembly with
test gas.
Apply the gas pressure of 1,375 × HSL and maintain it for 10 min for the same reason as noted in 7.2.2.
Then, still maintaining the pressure, the leakage shall be checked visually for any bubbles from hose
body and both coupling ends for 5 min. This check is performed under water by immersing the test
piece in a water bath.
Also, a gas leak detector or leak detection fluid may be applied to check leakage in the air.
Leakage can be tested by the permeation test during the first 15 min according to Method A.
The air contained in the reinforcement layer (trapped air), which comes out from perforated holes, can
be omitted unless they are abnormal.
7.3 Hydrostatic strength
7.3.1 Proof pressure test
When tested in accordance with ISO 1402, a hose assembly shall withstand a pressure of at least
2,1 × HSL for 5 min without bursting or visible loss of fluid.
As a test fluid, water or a mixture of water and glycol or oil can be used.
This is a non-destructive test.
7.3.2 Ultimate strength
The hose assembly shall be air oven aged for 70 h at 85 °C ± 1 °C.
Following the oven aging, when tested in accordance with ISO 1402, a hose assembly shall withstand
without bursting or visible loss of fluid with a pressure of a minimum of 5 times of HSL for 5 min.
Then, continue to pressurize until the hose assembly bursts and measure the pressure.
As a test fluid, water or a mixture of water and glycol or oil can be used.
This is a destructive test.
7.4 Electrical conductivity
When determined in accordance with ISO 8031:2009, 4.8, the bonding resistance of fuelling hose
assembly, from end fitting to end fitting, shall be no greater than 100 kΩ, in order to dissipate static
electricity.
This test shall be conducted with the hose un-pressurized.
The bonding resistance of the fuelling hose assembly may need to be no greater than 1 kΩ for
manufacturing quality control.
8 © ISO 2019 – All rights reserved

7.5 Tensile test of hose assembly
7.5.1 General
This test is modelling the scenario of the fuelling nozzle being connected to the vehicle while driving away.
This provision applies to a single hose assembly only. For an integrated supply and vent line hose
assembly, only the supply portion of the hose assembly shall be tested.
A hose assembly having a free length of 100 mm or longer shall withstand a longitudinal pull force of
3 000 N, as shown Figure 3, without structural damage or leakage after being subjected to accelerated
air oven aging. The hose shall comply with 7.3.1 and 7.4 after the tensile test.
Key
1 hose assembly
a
Direction of force.
Figure 3 — Tensile test of hose assembly
7.5.2 Test method
The hose assembly shall be air oven aged for 70 h at 85 °C ± 1 °C.
Following the oven aging, the hose assembly shall be cooled down to a room temperature of 20 °C ± 10 °C
for at least 2 h prior to the conduct of the tensile test. Then the tensile test shall be conducted at room
temperature.
The apparatus outlined in ISO 4671 shall be used for this test.
The hose assembly is then to be placed in a tensile testing machine and connected so that the end
couplings and hose are subjected to 3 000 N. With the testing machine adjusted for a rate of travel of
0,2 mm/s or slower, the pull force is to be applied until 3 000 N is attained.
At the completion of this test, hose assemblies shall be subjected to and shall comply with 7.3.1 and 7.4.
7.6 Vertical load strength
7.6.1 General
This test models the scenario of a person falling against the hose while the fuelling nozzle is connected
to the vehicle receptacle or a loop being generated during handling, as shown Figure 4.
Key
1 hose assembly
a
Direction of vertical load.
b
Direction of moment.
Figure 4 — Example of abnormal load
7.6.2 Test method
The test piece shall have a free length of 0,5 m between the couplings. This test shall be conducted at
20 ± 10 °C.
Connect one end of the coupling to the connecter fixed horizontally. Apply the vertical load of 340 N to
the other free end and maintain the load for 5 min.
After 5 min, remove the load and perform 7.3.1 and 7.4 for any abnormality.
7.7 Torsion strength
7.7.1 General
This test does not apply to a bonded supply/vent line. When tested in accordance with ISO 6802 with
the conditions listed below, a dispenser hose shall withstand 1 000 cycles of horizontally reciprocating
movements under atmospheric pressure without damage to the hose or couplings and without leakage
in excess of the rate specified in 7.3.1 as shown in Figure 5.
10 © ISO 2019 – All rights reserved

Key
1 offset
2 horizontal reciprocating motion
3 direction of torsion
Figure 5 — Torsion strength
7.7.2 Test method
The test apparatus is a Method 2 horizontally reciprocating manifold.
Offset the sample hose at the distance of four times of outside diameter of hose and mount the test
sample at the centre of the stroke making sure there is no twist.
The test shall be conducted under atmospheric pressure and at −40 °C. 1 000 cycles are required.
7.8 Pressure cycle test (Hydraulic-pressure impulse test)
7.8.1 General
This hydraulic test models hot creep conditions at a high temperature.
When tested at impulse pressure equal to 1,25 × HSL, the hose shall withstand a minimum of
100 000 impulse cycles without leakage or failure.
7.8.2 Apparatus
The apparatus for this test shall be in accordance with ISO 6803:2017, Clause 4.
7.8.3 Test fluid
As a fluid for this test, water, mixture of water and glycol or oil (i.e. from grade ISO VG 32 to ISO
VG 100 in ISO 3448) can be used. Circulate the fluid at a rate sufficient to maintain a uniform fluid
temperature within the test pieces. Other fluids may be used as agreed upon between the customer and
the manufacturer.
7.8.4 Test temperature
The test fluid shall be circulated through the test piece at 65 °C ± 3 °C.
7.8.5 Test piece
Test pieces shall be complete hose assemblies with suitable end couplings attached. Unless otherwise
specified, test four unaged hose assemblies with end couplings which have been attached for not more
than 30 days.
Calculate the necessary free length of the hose in the test piece as shown in Figure 6.
For values of d less than 25,4 mm, use d = 25,4 mm for the +2d term in the expression for the hose free
length, so that the hose between the coupling shell and the start of the bend radius is straight.
+1 +8
The actual free hose length shall agree with the calculated free hose length to within % or mm ,
0 0
whichever is greater.
12 © ISO 2019 – All rights reserved

Key
r minimum bend radius
d hose outside diameter
Figure 6 — Test piece for pressure cycle test
7.8.6 Procedure
Connect the test pieces to the apparatus. The test pieces shall be installed in accordance with Figure 6.
Test pieces of hose shall be bent through 180°.
Bring the test fluid to the test temperature and then apply a pulsating pressure equal to 100 % of
1,25 × HSL internally to the hose assemblies at a uniform rate between 0,1 Hz and 0,4 Hz. Record the
pulse rate used. The pressure cycle shall fall within the shaded area of Figure 7.
The pressurization shall be stopped and the impulse test unit shall be allowed to cool down the
temperature of the test fluid to room temperature of 30 °C ± 10 °C at every 30 000 cycles of impulse cycles.
Accelerated cool down procedures, i.e. fans, heat exchangers, etc., may be used to speed up the cooling
process.
At every cool down, check test assemblies to ensure they are clean and dry. With fluid heater turned off,
resume the test and observe and note leakage for 1 000 impulse cycles.
After cool down, raise the fluid temperature to the specified temperature and restart the impulse cycle
until next cool down. Run the test until the hose fails or the number of required cycles is performed.
If a test is stopped before completion of the minimum number of cycles and then restarted, leakage may
occur at the hose/coupling junction upon restarting the test and until the test temperature is reached.
Leakage less than class 4 as defined in ISO/TR 11340 does not constitute a failure of the hose assembly.
Any leakage should be reported in accordance with the classification in ISO/TR 11340.
There shall be no leakage or o
...