SIST EN 1474-2:2009

SLOVENSKI STANDARD
oSIST prEN 1474-2:2007
01-februar-2007
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Installation and equipment for liquefied natural gas - Design and testing of marine
transfer systems - Part 2: Design and testing of transfer hoses
Anlagen und Ausrüstung für Flüssigerdgas - Auslegung und Prüfung von
Schiffsübergabesystemen - Teil 2: Auslegung und Prüfung von Übergabeschläuchen
Installations et équipements de gaz naturel liquéfié - Conception et essais des systemes
de transfert marins - Partie 2: Conception et essais des tuyaux de transfert
Ta slovenski standard je istoveten z: prEN 1474-2
ICS:
75.200 2SUHPD]DVNODGLãþHQMH Petroleum products and
QDIWHQDIWQLKSURL]YRGRYLQ natural gas handling
]HPHOMVNHJDSOLQD equipment
oSIST prEN 1474-2:2007 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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EUROPEAN STANDARD
DRAFT
prEN 1474-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2006
ICS 75.200

English Version
Installation and equipment for liquefied natural gas - Design and
testing of marine transfer systems - Part 2: Design and testing of
transfer hoses
Installations et équipements de gaz naturel liquéfié -
Conception et essais des systèmes de transfert marins -
Partie 2: Conception et essais des tuyaux de transfert
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 282.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other language
made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same
status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 1474-2:2006: E
worldwide for CEN national Members.

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prEN 1474-2:2006 (E)
Contents Page
Foreword.3
1 Scope .4
2 Normative references .4
3 Terms, definitions and abbreviations.4
4 Description of typical LNG transfer hose designs and accessories.4
5 Design features of the LNG transfer hoses and transfer hoses assemblies.9
6 Inspection and tests .14
7 Quality Assurance and Control.18
8 Documentation.19
Annex A (informative) Purchasing Guidelines table.20
Annex B (normative) Type approval and routine tests for LNG hoses and hoses assemblies.26
Bibliography .28
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prEN 1474-2:2006 (E)
Foreword
This document (prEN 1474-2:2006) has been prepared by Technical Committee CEN/TC 282 “Installation and
equipment for LNG”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
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prEN 1474-2:2006 (E)
1 Scope
This part of EN 1474 gives general guidelines for the design, material selection, qualification, certification, and
testing details for Liquefied Natural Gas (LNG) transfer hose for offshore transfer or on coastal weather- exposed
facilities.
To avoid unnecessary repetition, cross-reference to EN 1474-1 Design and Testing of Transfer Arms, is made for
all compatible items, and for References, Definitions and Abbreviations. Where additional References, Definitions
and Abbreviations are required specifically for LNG hoses, they are listed in this part.
For details of specific LNG transfer system architectures reference should be made to EN 1474-3.
Hoses used for LNG transfer are normally large bore: typically from DN 250 (10”) to above DN 400 (16”) and more,
with working design pressures in the range of 10 bar to 20 bar in order to meet the minimum flow rate from the
3
facility of 10 000 m /hour with a practical number of hoses used for LNG transfer and vapour return.
Transfer hoses have to be durable when operating in the marine environment and to be flexible with a minimum
bending radius compatible with handling and the operating requirements of the transfer system.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references,
only the edition cited applies. For undated references, the latest edition of the referenced document (including any
amendments) applies.
EN 1474-1, Installation and Equipment for Liquefied Natural Gas — Design and Testing of Marine Transfer
Systems — Part I: Design and Testing of Transfer Arms.
EN 1474-3, Installation and Equipment for Liquefied Natural Gas — Design and Testing of Marine Transfer
Systems — Part III: Offshore Transfer Systems.
3 Terms, definitions and abbreviations
For the purposes of this document, the terms and definitions given in EN ISO 7369:2004 "Pipework — Metal hoses
and hose assemblies — Vocabulary" and EN ISO 8330:2002 "Rubber and plastic hoses and hose assemblies —
Vocabulary" apply.
For the purpose of this document hose assembly means the hose complete with end fittings, hose handling and
lifting devices (pad eyes, collars, …), as described in clause 4.1.1.
4 Description of typical LNG transfer hose designs and accessories
4.1 A LNG transfer hose system shall consist of the following
4.1.1 A flexible hose assembly, comprising
 an inner leak-proof barrier to provide primary flow path and containment;
 reinforcement layers to provide structural support;
 an exterior leak-proof barrier to provide an external protection (note: this depends on the hose design, see
clause 4.2);
 the associated end terminations and connectors;
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prEN 1474-2:2006 (E)
 identification collars,
and if required:
 a leak detection system;
 an insulation system (to minimize build up of external ice);
 intermediate leak barrier(s);
 bending stiffeners or restrictors;
 hose handling device(s) (padeye or lifting lugs, lifting collar, …);
 buoyancy.
NOTE The leak proof barrier of a composite hose is comprised of many individual layers forming a labyrinth seal.
4.1.2 Connection System to LNGC
 The hose extremity connector flanges shall permit the mounting of a QCDC or a spool piece or permit direct
connection to LNGC or LNG terminal or another hose assembly.
(A description of QCDC is given in EN 1474-1 clause 6).
 Hubs, or other connectors if equivalent or superior to flanges, may be used if agreed between Purchaser and
Vendor.
4.1.3 Emergency Release System
 The hose extremity connector shall permit the mounting of an Emergency Release System with Valves and
ERC (Emergency Release Coupler).
(A description of Emergency Release System is given in EN 1474-1 clause 5 and EN 1474-3 clause 7).
4.1.4 Handling
 The hose shall include necessary fittings for safe handling, coupling & uncoupling either from the LNGC or the
onshore or offshore LNG terminal system as required by the system design (refer to EN 1474-3 clause 6).
4.1.5 Power Systems
 The hose may support (e.g. piggy back mounted) hydraulic or pneumatic hoses, electric cables for the
powering of the ERS and QCDC systems (refer to EN 1474-3 clauses 6 and 7).
4.1.6 Leak detection, monitoring and Alarm Systems
 If required by the Purchaser the hose shall incorporate leak detection system e.g. gaseous nitrogen bleeding in
the annular space (see clause 5.10).
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prEN 1474-2:2006 (E)
4.2 Classification of LNG transfer hoses according to their method of construction
At present LNG transfer hoses are classed in two types according to their method of construction:
 those based on a reinforced corrugated metal hose construction, hereafter called Corrugated Metal Hose;
 those based on a construction in which polymeric films and fabrics are entrapped between a pair of close
wound helical wires, hereafter called Composite Hose;
 as the technology develops, other types of hose may become available and are also to be considered covered
by this standard.
4.2.1 Corrugated metal hoses
 Inner layer
The inner layer is made of stainless steel corrugations (sometimes called bellows). This ensures the inner leak-
proofness of the structure, as well as sustaining the inner radial pressure.
 Armour layers (if required)
These armours sustain the axial loading whilst providing an initial thermal insulation.
 Spiral layer (if required)
This layer ensures that the armours remain in place, as well as providing some thermal insulation.
 Thermal insulation layers
This layer (or series of layers) ensures that the inner temperature is conserved whilst preventing any build-up of ice
on the exterior of the hose.
 Intermediate and outer leak-proof layers
The intermediate sheath gives the hose a double annulus, thus permitting the detection of any leak of LNG as soon
as it may occur. The external sheath prevents any ingress of water from the exterior.
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Key
1 Leakproof Layer
2 Insulation
3 Leakproof Layer
4 Insulation
5 Frette
6 Armours
7 Leakproof Layer
8 Inner Corrugated Bellows

Figure 1 — Typical hose – reinforced corrugated metal hose family
Depending on the design, the outer leak proof layer can be a corrugated stainless steel hose similar to the inner
hose. In this case the annular gap between inner and outer hose may be evacuated. The pressure supervision of
this annular gap results in a leak detection of inner and outer hose. The thermal insulation is maintained by layers
of super insulation inside the evacuated annular gap.
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prEN 1474-2:2006 (E)

Key
1 Pumping port
2 Armouring
3 Corrugated outerpipe
4 Corrugated innerpipe
5 Super insulation vacuum
6 Vacuum supervision Leal detection
Figure 2 — Sketch of a LNG flexible hose with vacuum installation option
The metal hose construction shall ensure that all materials are used within their individual range of temperature.
End fitting assembly:
The end fitting assembly is made of stainless steel, and ensures 2 primary functions.
The flexible termination, which incorporates the different layers of the flexible and ensures the integrity of each
layer at its end. The construction is designed to allow the immediate detection of any LNG leak into the inner
annulus.
The end connector, which is connected to the associated piping at each end of the flexible. This will typically be a
standard ANSI flange (refer also to clause .1.2 Connection system).
4.2.2 Composite hoses
A composite hose consists of multiple polymeric film and fabric layers trapped between two wire helices which give
the hose its shape, one being internal and one being external. Broadly, the film layers provide a fluid-tight barrier to
the conveyed product and the fabric layers provide the mechanical strength of the hose.
Composite hoses are typically mandrel built, the length and diameter of the mandrel determining the finished hose
length and bore.
In sequence, starting from the bore, the construction is as follows:
a) an inner metallic wire helix applied at a pre-determined close pitch;
b) polymeric fabric layers forming the bore material;
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c) a pack of many polymeric film layers. The complete film pack achieves a tubular form and provides the fluid
tight barrier to the conveyed product;
d) a pack of many polymeric fabric layers which reinforce the hose;
e) an outer metallic wire helix applied at half a pitch offset to the inner wire under tension. This forms the hose
into the required convoluted structure.
The number and arrangement of the layers in steps c) and d) is specific to the hose size and application. The
polymeric film and fabric materials are selected to be compatible with the conveyed product and the extremes of
operating temperature.
Since the film and fabric layers are held securely by the inter-action of the wire helices, it is not necessary to bond
the layer together in the hose e.g. by vulcanization.
Since the internal wire is an essential feature, composite hoses are always of rough bore construction.
Further layers may be included outside the external helical wire to provide insulation, buoyancy and an outer
protective layer as required by the specific application.

Key
1 Inner wire
2 Film
3 Fabric
4 Outer wire
Figure 3 — Typical hose – composite hose family
5 Design features of the LNG transfer hoses and transfer hoses assemblies
The hose forms part of an overall system for the transfer of LNG - the requirements which will dictate the exact
design of the hose (e.g. static and dynamic movements, …) refer to EN 1474-3 clause 6. The design process and
required information is outlined below.
5.1 Application data required
The hose will form part of an overall system for the transfer of LNG - the requirements of which will dictate the
exact design of the hose.
In order that the Design Loads are calculated, the Purchaser shall specify the fixed loads, the operational
loads, any accidental loads that may occur, the intended service and the operating weather limits (wind, wave
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and temperature), offload duration and the maximum allowable heat influx or maximum boil off rate or a rate or a
‘no icing’ criterion.
5.2 Selection of hose length
The overall hose length will be dictated by the system design and shall be sufficient to meet both storage and
operational conditions.
For aerial hose configuration the hose length shall be determined by a dynamic analysis of the system ensuring
that the hose bend radius and maximum loads are not exceeded and that the operability window is sufficient (note:
bending radius is measured to the hose center line).
Depending on the length, system design and type, and other factors such as shipping requirements, the hose shall
be either supplied as a continuous length or as a string of discrete sections.
The hose length used in the system will be such that the motion envelops as defined in EN 1474-1 clause 4 and in
EN 1474-3 clause 6 are met.
Hose length shall take into account the elongation of the hose under pressure or its own weight. This elongation
must be consistent with the transfer system design.
5.3 Service life
The required service life shall be specified by the Owner and is likely to be a requirement for the entire transfer
system. The system design shall ensure that the life of the hose meets this requirement.
The calculation of hose life will take into account the cumulative effects of the number and amplitude of flexure,
tensile, pressure and temperature cycles in operation, environmental ageing and the consequences of emergency
disconnections and internal pressure surge in service.
A typically minimum service life of 5 years of the hose system is contemplated.
The relationship between the service life and fatigue life is to be agreed by the manufacturer and purchaser and
shall be documented.
5.4 Selection of hose size
The Purchaser shall specify flow rate, maximum allowable working pressure, temperature, composition of product
and the maximum allowable head loss. The number of hoses to be used shall be either predefined by the system or
can be tailored to suit size limits and flow rate requirements.
The Vendor shall to specify maximum allowable working pressure (design pressure) of the hose assembly to allow
the purchaser to size pressure relief devices etc.
5.5 Selection of buoyancy
The transfer system shall be such as the hose is either floating, aerial, or the purchaser will specify the degree of
buoyancy if it is required (this will also include submersion requirements).
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For floating hose systems the hose shall have not less than 20 % reserve buoyancy, calculated by:
D (W ×W )
B H W
%RB= ×100 % (1)
(W +W )
B W
where
%RB Percentage Reserve Buoyancy;
D Weight of seawater displaced by hose when fully submerged including seawater displaced by integral
H
buoyancy and seawater inside hose bore;
W Weight of empty hose in air including buoyancy material;
H
W Weight of seawater content in hose.
W
5.6 Selection of insulation
If required the hose shall have sufficient insulation to minimize build-up of ice on the exterior of the hose itself and
to limit heat leak.
The Purchaser shall to specify the operating weather limits (ambient temperature, humidity wind speed and
temperature), offload duration and the maximum allowable heat influx or maximum boil off rate or a "no icing"
criterion.
NOTE The insulation requirements will also be affected by the overall length of the hose and the QC/DC, ERS etc.
5.7 Basic Design Parameters
The MBR (Minimum Burst Pressure) ratio to the MAWP (Maximum Allowable Working Pressure) is given in
clause 6.
The FAT (Factory Acceptance Test) pressure is given in clause 6.
Maximum flow velocity see EN 1474-1 clause 4.2.
Maximum allowable applied twist shall be specified by the Vendor.
The hose shall be designed ensuring the compatibility of each component (layer) of the hose with its function (e.g.
LNG and NG service and testing values).
5.8 Component details – End fitting
The end fittings of any hose comprise of two main parts:
 the termination;
 the connector.
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Illustration of an end fitting (typical, may vary depending on the hose design):

Key
1 Handling collar
2 Identification collar
3 Bending stiffener (optional)
4 Connector
5 Termination
6 End Fitting
Figure 4 — Typical hose – composite hose family

5.8.1 Termination
The termination shall ensure the following functions:
 mechanical attachment of all component layers of the hose which resist against internal pressure, traction and
torsion;
 provide a leak-proof seal against the transported fluid and/or gas;
 provide a leak-proof seal against ingress of humidity or water from the outer environment.
The mounted end fittings shall not be the weak pressure bearing points of the hose assembly.
The end fitting shall comply with the system fatigue criteria.
In the case of a burst test for proof purposes, the end fittings shall never separate from the hose.
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5.8.2 Connector
The connector shall either be machined into the end termination or welded to it in accordance with a written
procedure. The type of connector shall be specified by the purchaser and /or the system requirements.
5.8.3 Bending stiffener/restrictor (optional)
This is an optional item, mounted onto the hose at either one or both terminations, when required. It has the
function of providing a smooth transition of bending forces, if existing, from the end fitting to the hose structure, and
provides extra resistance to over bending.
The inclusion of a bend stiffener is at the Vendors discretion following review of the operational conditions.
5.9 Hose handling / lifting device
Additional items such as the hose handling device (pad eyes or collar etc.), QC/DC and ERS shall be designed as
part of the particular system and in accordance with EN 1474-1 clause 6 and EN 1474-3 clauses 4.3, 5.4 and 8.
Specific hose handling instructions will be issued as part of the system.
Appropriate hose handling instructions shall be supplied with each order to allow correct handling during transport
and at others times prior to inclusion in the system.
A hose handling/lifting device shall be designed and proof tested to allow for safe handling of the complete hose.
When requested and upon mutual agreement between the Vendor and Purchaser, it can be designed to handle
other equipment which could be attached to either end of the hose.
Appropriate arrangements are to be provided to securely keep the hoses in stored position when not in service or
whilst being transported.
5.10 Safety systems
Hose and Connectors:
The ERS and QC/DC shall comply to EN 1474-1 clauses 5.4 and 6 and will be defined by Purchaser and or system
requirements.
Leak detection (optional):
Corrugated metal hoses:
Gas detection if fitted is to be provided as a warning of leak of the hose allowing appropriate action to be taken.
The system shall conform to one of the following:
 leak detection of only the inner hose. In case of a break of the inner pipe, the supervision system gives alarm
signal to the terminal, but NG escapes to the environment;
 leak detection only at the end fitting to provide detection of seal failure;
 leak detection of only the inner hose. In case of a break of the inner hose, the supervision system gives alarm
signal to the terminal. For small leaks the escaping gas is exhausted from the annular gap. The annular gap is
not able to withstand the design pressure of the hose;
 leak detection of the inner hose and an outer hose if it is provided. In case of a leak in the outer hose, the
supervision gives a certain alarm to the terminal. In case of a leak in the inner hose, the supervision gives
alarm to the terminal and the escaping gas is covered by the outer hose. The outer hose is able to withstand
design pressure of hose.
Composite hoses:
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It is envisaged that not all hoses will have an annulus running along their entire length. In these cases leak
detection shall be provided at the end fittings but will not be provided for the main hose body.
Fire resistance:
Fire resistance requirements if specified shall be mutually agreed between purchaser and vendor.
Electrical safety requirements:
Continuity, insulation flange (reference to EN 1474-1 clause 5.4), see also EN 1474-3 clause 7.6.
5.11 Connection to the ship
Connection to the LNG carrier by the mid-ship manifold will be achieved by pulling the LNG hose assemblies by the
means of their dedicated connection on the hose system.
In case a spool piece is used, it shall be designed to ensure that all work and connections are carried out over the
side of the LNG carrier and not over the deck.
5.12 Hydraulic and Electric control systems
Hydraulic and Electric control systems shall be built to meet the number and diameter of hoses required. Each
system shall be dimensioned to operate the QCDC and ERS as well as any connection and stand-by winches.
6 Inspection and tests
Important foreword
This clause gives the list of the tests to be performed with the corresponding limits to be demonstrated, but is not
aimed to give the full description of the tests procedures, which may vary between hoses manufacturers and hoses
technologies. This is because at the time of writing these procedures, no such LNG hose is on duty on an LNG
project. Accordingly there is room for improvement of this clause 6 with more specific inspection and test
requirements to be left to a further revision of EN 1474-2.
As a general principle, all parameters / characteristics must be proved by testing.
The Annex B (normative) "type approval and routine testing for LNG marine hose assemblies" gives a summary of
the tests to be performed.
In this clause 6:
[ND]Non destructive – a test that is not expected to cause permanent damage to the hose and so the hose may be
used in subsequent tests.
[D] Destructive – a test that will cause permanent damage to the hose and one requiring the hose to be dissected
for examination purposes and the effect of that test on the hose structure and/or end termination integrity to be
assessed.
The following definitions are used on pressure ratings:
Maximum Allowable Working Pressure [MAWP] – The maximum pressure (gauge) across the entire specified
temperature range which the hose may be exposed to and may be operated at. It is commonly used by terminals to
define their cargo system pressure capabilities (i.e. pump shut-in plus any static head or cargo system safety valve
relief setting. This pressure rating is not expected to account for dynamic surge pressures, but does nominal
pressure variations during cargo transfer operations). According to IMO IGC Code (complete reference is given in
Bibliography) the specified MAWP should not be less than 10 bar gauge.
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NOTE Working Pressure (or operating pressure) is deemed a common expression to define the normal pressure that
would be experienced by the hose during cargo transfer. (This would generally reflect the cargo pump operating pressures or
hydrostatic pressure from a static system). Working Pressure is not used in present document.
Proof Pressure [PP] – The pressure to which the hose is tested (i.e. during a Factory Acceptance Test) to prove its
structural integrity when subject to internal pressure. According to IMO IGC Code (complete reference is given in
Bibliography) this pressure test at ambient temperature shall be not less than 1,5 × MAWP and not more than two-
fifths of its bursting pressure. The proof pressure addresses the occasional additional pressure caused by surge
(i.e. when the moving cargo fluid is rapidly stopped as in the situation where marine vessel or terminal valve is
quickly closed). The surge pressure would be additive to the existing pressure in the cargo system. Surge pressure
will depend on the particular cargo transfer system and would need to be assessed for each marine terminal cargo
transfer system).
Minimum Burst Pressure [MBP] – The minimum pressure at which the hose will rupture due to the application of
bore pressure in a hose with sealed end caps. According to IMO IGC Code (complete reference is given in
Bibliography) this shall be not less than 5,0 × MAWP (as defined above) at the extreme service temperature.
Laboratory Testing
All test procedures and their parameters should be in accordance with the Vendor written test procedures and
agreed with Purchaser.
1) Ambient Mechanical Properties of all Materials – ascertain that the mechanical properties of the materials
are suitable for their intended application and within specification limits;
2) cryogenic Mechanical Properties of all Materials which have to work at cryogenic temperature (these may
be supplemented with supplier data) – ascertain that the mechanical properties of the materials are
suitable for their intended application at cryogenic temperatures;
3) effect of LNG Exposure an All Materials which have to work at cryogenic temperature – ascertain that the
mechanical properties of the materials are not detrimentally affected (or quantify the effect within
acceptable and defined limits) by exposure to LNG/NG;
4) effect of ambient climatic Exposure on All Materials (exposed to atmosphere) – ascertain that the effects
of such exposure do not adversely affect the performance of the materials over the hose design life;
NOTE This test could be combined with test 2 if mutually agreed between Purchaser and Vendor.
5) effect of Marine Environment (e.g. Corrosion of Metallic Components) on All Exposed Layers (exposed to
the Marine Environment) – ascertain that the effects of the marine environment do not adversely affect the
...