oSIST prEN ISO 13628-14:2012

SLOVENSKI STANDARD
01-januar-2012
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Petroleum and natural gas industries - Design and operation of subsea production
systems - Part 14: Subsea high integrity pressure protection systems (HIPPS) (ISO/DIS
13628-14:2011)
Erdöl- und Erdgasindustrie - Auslegung und Betrieb von Unterwasser-
Produktionssystemen - Teil 14: Integriertes Drucksicherungssystem für den
Unterwassereinsatz (HIPPS) (ISO/DIS 13628-14:2011)
Industries du pétrole et du gaz naturel - Conception et exploitation des systèmes de
production immergés - Partie 14: Systèmes immergés de protection contre les pressions
à haute intégrité (ISO/DIS 13628-14:2011)
Ta slovenski standard je istoveten z: prEN ISO 13628-14
ICS:
75.180.10 Oprema za raziskovanje in Exploratory and extraction
odkopavanje equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
DRAFT
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2011
ICS 75.180.10
English Version
Petroleum and natural gas industries - Design and operation of
subsea production systems - Part 14: Subsea high integrity
pressure protection systems (HIPPS) (ISO/DIS 13628-14:2011)
Industries du pétrole et du gaz naturel - Conception et Erdöl- und Erdgasindustrie - Auslegung und Betrieb von
exploitation des systèmes de production immergés - Partie
Unterwasser-Produktionssystemen - Teil 14: Integriertes
14: Systèmes immergés de protection contre les pressions Drucksicherungssystem für den Unterwassereinsatz
à haute intégrité (ISO/DIS 13628-14:2011) (HIPPS) (ISO/DIS 13628-14:2011)
This draft European Standard is submitted to CEN members for parallel enquiry. It has been drawn up by the Technical Committee
CEN/TC 12.
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 CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, 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: Avenue Marnix 17, B-1000 Brussels
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN ISO 13628-14:2011: E
worldwide for CEN national Members.

Contents Page
Foreword .3

Foreword
This document (prEN ISO 13628-14:2011) has been prepared by Technical Committee ISO/TC 67 "Materials,
equipment and offshore structures for petroleum, petrochemical and natural gas industries" in collaboration
with Technical Committee CEN/TC 12 “Materials, equipment and offshore structures for petroleum,
petrochemical and natural gas industries” the secretariat of which is held by AFNOR.
This document is currently submitted to the parallel Enquiry.
Endorsement notice
The text of ISO/DIS 13628-14:2011 has been approved by CEN as a prEN ISO 13628-14:2011 without any
modification.
DRAFT INTERNATIONAL STANDARD ISO/DIS 13628-14
ISO/TC 67/SC 4 Secretariat: ANSI
Voting begins on Voting terminates on

2011-10-13 2012-03-13
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION    МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ    ORGANISATION INTERNATIONALE DE NORMALISATION

Petroleum and natural gas industries — Design and operation
of subsea production systems —
Part 14:
Subsea high integrity pressure protection systems (HIPPS)
Industries du pétrole et du gaz naturel — Conception et exploitation des systèmes de production immergés —
Partie 14: Systèmes immergés de protection contre les pressions à haute intégrité
ICS 75.180.10
ISO/CEN PARALLEL PROCESSING
This draft has been developed within the International Organization for Standardization (ISO), and
processed under the ISO-lead mode of collaboration as defined in the Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member bodies for a parallel
five-month enquiry.
Should this draft be accepted, a final draft, established on the basis of comments received, will be
submitted to a parallel two-month approval vote in ISO and formal vote in CEN.

In accordance with the provisions of Council Resolution 15/1993 this document is circulated in
the English language only.
Conformément aux dispositions de la Résolution du Conseil 15/1993, ce document est distribué
en version anglaise seulement.

To expedite distribution, this document is circulated as received from the committee
secretariat. ISO Central Secretariat work of editing and text composition will be undertaken at
publication stage.
Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du
secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au
Secrétariat central de l'ISO au stade de publication.

THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE
REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME
STANDARDS TO WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.
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.
©  International Organization for Standardization, 2011

ISO/DIS 13628-14
Copyright notice
This ISO document is a Draft International Standard and is copyright-protected by ISO. Except as permitted
under the applicable laws of the user’s country, neither this ISO draft nor any extract from it may be
reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic,
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Reproduction may be subject to royalty payments or a licensing agreement.
Violators may be prosecuted.
ii © ISO 2011 – All rights reserved

ISO/DIS 13628-14
Contents Page
Foreword . v
Introduction . vii
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviations . 2
3.1 Terms and definitions . 2
3.2 Symbols and abbreviations . 5
4 General requirements . 6
4.1 Principle. 6
4.2 Production characteristics . 8
4.3 Flowline rupture considerations . 8
4.4 Process hazard and risk analysis . 8
4.5 Selection and determination of SIL . 9
4.6 Safety requirement specification (SRS) . 9
5 Procedure – Basic design. 11
5.1 Principle - Design basis requirements . 11
5.2 Modes of failure . 14
5.3 Temperature . 14
5.4 Pressure . 14
5.5 Control system . 15
5.6 Materials class rating . 17
5.7 External hydrostatic pressure . 17
5.8 Transportation and installation conditions . 18
5.9 Equipment design . 18
5.10 Control systems . 19
6 Materials and equipment . 22
6.1 HIPPS final element equipment . 22
6.2 HIPPS control system and final element-mounted control devices. 24
6.3 Welding . 25
6.4 Coatings (external) . 25
7 Quality control . 25
7.1 General . 25
7.2 HIPPS closure devices—PSL . 26
7.3 Structural components . 27
7.4 Lifting devices . 27
7.5 Cathodic protection . 27
7.6 Storing and shipping . 27
8 Equipment marking . 28
8.1 General . 28
8.2 Pad eyes and lift points . 28
9 Validation. 28
9.1 General . 28
9.2 Validation for HIPPS closure devices (isolation valve) and actuator . 29
9.3 Validation for monitor/bleed, bypass, injection valves . 29
9.4 Validation for DCV . 29
9.5 Validation of sensors, logic solvers, and control system devices. 30
9.6 Validation of HIPPS final element . 31
ISO/DIS 13628-14
9.7 Estimating SIL for HIPPS final element components. 31
10 Commissioning and installation . 32
10.1 General . 32
10.2 Planning . 32
10.3 Installation . 34
10.4 Commissioning . 34

iv © ISO 2011 – All rights reserved

ISO/DIS 13628-14
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 13628-14 was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore
structures for the petroleum, petrochemical and natural gas industries, Subcommittee SC 4, Drilling and
production equipment.
This is the first edition of ISO 13628-14.
ISO 13628 consists of the following parts, under the general title Petroleum and natural gas industries —
Design and operation of subsea production systems:
 Part 1: General requirements and recommendations
 Part 2: Flexible pipe systems for subsea and marine applications
 Part 3: Through flowline (TFL) systems
 Part 4: Subsea wellhead and tree equipment
 Part 5: Subsea umbilicals
 Part 6: Subsea production control sytems
 Part 7: Completion/workover riser systems
 Part 8: Remotely Operated Vehicle (ROV) interfaces on subsea production systems
 Part 9 Remotely Operated Tool (ROT) intervention systems (combined into Part 8)
 Part 10: Specification for bonded flexible pipe
 Part 11: Flexible pipe systems for subsea and marine applications
 Part 12: Dynamic production risers (under preparation)
 Part 13: Vacant
ISO/DIS 13628-14
 Part 14: Subsea high integrity pressure protection systems (HIPPS)
 Part 15: Subsea structures and man ifolds (under preparation)
 Part 16 Recommended practice for flexib le pipe ancilliary equipment (under preparation)
 Part 17: Specification for flexible pipe ancillary equipment (under preparation)
vi © ISO 2011 – All rights reserved

ISO/DIS 13628-14
Introduction
The part of International Standard ISO 13628 has been prepared to provide general recommendations and
overall guidance for the designa and operation of remotely operated tools comprising ROT and ROV tooling,
used on subsea production systems for the petroleum and natural gas indsutries worldwide.
Specific design requirements are used where a standard design or operating principle has been adopted in
the industry for a period of time. Requirements valid for certain geographic areas or environmental conditions,
are included where applicable.
The functional recommendations for the tooling systems and interfaces on the subsea production system
allow alternative solutions to suite field specific requirements. The intention is to facilitate and complement the
decision process rather than replace individual engineering judgement and, where requirements are non-
mandatory, to provide positive guidance for hte selection of an optimum solution.
DRAFT INTERNATIONAL STANDARD ISO/DIS 13628-14

Petroleum and natural gas industries — Design and operation
of subsea production systems —
Part 14:
Subsea high integrity pressure protection systems (HIPPS)
1 Scope
This part of the International Standard ISO 13628 series addresses the requirements for the use of high integrity
pressure protection systems (HIPPS) for subsea applications. ISO 10418, IEC 61508, and IEC 61511 specify
the requirements for onshore, topsides, and subsea safety instrumented systems (SIS’s) and are applicable to
HIPPS, which are designed to autonomously isolate downstream facilities from overpressure situations. This
International Standard integrates these requirements to address the specific needs of subsea production. These
requirements cover the HIPPS pressure sensors, logic solver, shutdown valves, and ancillary devices including
testing, communications, and monitoring subsystems.
2 Normative references
The following referenced documents are indispensable for the application of this International Standard. For
dated references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 10418, Petroleum and natural gas industries – Offshore production installations – Basic surface safety
systems
1)
ISO 10423 , Petroleum and natural gas industries,
2)
ISO 13628-1 , Petroleum and natural gas industries, Design and operation of subsea production systems,
General requirements and recommendations
3)
ISO 13628-3 , Petroleum and natural gas industries, Design and operation of subsea production systems,
Through flowline (TFL) systems
4)
ISO 13628-4 , Petroleum and natural gas industries, Design and operation of subsea production systems,
Subsea wellhead and Christmas tree equipment
5)
ISO 13628-6 , Petroleum and natural gas industries, Design and operation of subsea production systems,
Subsea Production Control Systems

1) API 6A, Specification Wellhead and Christmas Tree Equipment, is equivalent to ISO 10423.
2) API 17A, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, is
equivalent to ISO 13628-1.
3) API 17C, Recommended Practice on TFL (Through Flowline) Systems, is equivalent to ISO 13628-3.
4) API 17D, Recommended Practice on Subsea Wellhead and Christmas Tree Equipment, is equivalent to ISO 13628-4.
5) API 17F, Specification for Subsea Production Control Systems, is equivalent to ISO13628-6.
ISO/DIS 13628-14
6)
ISO 13628-8 , Petroleum and natural gas industries, Design and operation of subsea production systems,
Remotely operated vehicle (ROV) interfaces.
NOTE ISO 13628-8 will be withdrawn and r eplaced by ISO 13628-13 when published. In this document, any
reference to ISO 13628-8 should be replaced with ISO 13628-13 when published and available.
IEC 61508, Part 1 to Part 4, Functional safety of electrical/electronic/programmable electronic safety-related
systems
IEC 61511, Part 1, Functional safety—Safety instrumented systems for the process industry sector
API Recommended Practice 6HT, Heat Treatment and Testing of Large Cross Section and Critical Section
Components
ANSI/ASME B31.3, Process Piping
ANSI/ASME B31.8, Gas Transmission and Distribution Piping Systems
AWS D1.1, Structural Welding Code—Steel
ANSI/SAE J343, Test and Test Procedures for SAE 100R Series Hydraulic Hose and Hose Assemblies
ANSI/SAE J517, Hydraulic Hose
SAE AS 4059, Aerospace Fluid Power—Cleanliness Classification for Hydraulic Fluids
3 Terms, definitions, symbols and abbreviations
3.1 Terms and definitions
For the purposes of this document, the following definitions apply.
3.1.1
alternative pressure source
injection fluid used for valve seal test not to exceed the RWP of the HIPPS at its depth rating
NOTE Injection fluid can be any fluid that can be introduced into the system not only for testing but also for flushing
or preventing hydrates from forming.
3.1.2
commissioning
functional validation of equipment and facilities prior to initiating operations
3.1.3
dangerous failure
failure which has potential to put safety-related system in a hazardous or fail-to-function state

6) API 17H, Recommended Practice for Remotely Operated Vehicle (ROV) Interfaces on Subsea Production Systems, is
equivalent to ISO 13628-8.
2 © ISO 2011 – All rights reserved

ISO/DIS 13628-14
3.1.4
final element
part of a SIS which implements the physical action necessary to achieve a safe state
3.1.5
fortified section
piping and equipment with an intermediate pressure rating somewhere between the SIP (high) and MAWP
(low) ratings
3.1.6
hardware fault tolerance
HFT
ability of a functional unit to continue to perform a required function in the presence of faults or errors
NOTE In determining the HFT, no account is taken of other measures that may control the effects of faults such as
diagnostics, and where one fault directly leads to the occurrence of one or more subsequent faults, these are considered
as a single fault.
3.1.7
high integrity pressure protection system
HIPPS
mechanical and electrical-hydraulic SIS used to protect production assets from high-pressure upsets
3.1.8
maximum allowable operating pressure
MAOP
maximum pressure at which a system is allowed to operate that shall not be exceeded in steady state
conditions
3.1.9
maximum operating pressure
maximum pressure predicted including deviations from normal operations, such as start-up/shutdown, process
flexibility, control requirements, and process upsets
3.1.10
operating pressure
pressure in the equipment when the plant operates at steady state condition, subject to normal variation in
operating parameters
3.1.11
overpressure source
one or a combination of sources which can create a pressure buildup beyond the RWP of hardware
downstream
NOTE Examples include the reservoir, pressure or boosting equipment (i.e. pump/compressor) manifolds, or other
fluid injection sources.
3.1.12
pipeline
piping, risers, and appurtenances installed for transporting oil, gas, sulfur, and produced waters
3.1.13
process hazard
process upset that could result in loss of life, injury to personnel, pollution, or damage to production assets
such as overpressure and the subsequent rupture or failure of the process equipment
ISO/DIS 13628-14
3.1.14
rated working pressure
RWP
maximum internal pressure that the equipment is designed to contain and/or control
3.1.15
reliability
likelihood of a given piece of safety-related equipment to remain in operation for the expected duration
3.1.16
risk analysis
determination of the frequency of the event (e.g. overpressure) and the ability of safeguards (e.g. HIPPS) to
reduce the frequency or the consequence such that the event becomes tolerable, either by being very rare
(unlikely) or lessening the impact
3.1.17
safe failure
failure which does not have the potential to put the safety-related system in a hazardous or fail-to-function
state
3.1.18
safe failure fraction
SFF
ratio of the average rate of safe failures plus dangerous detected failures of the subsystem to the total
average failure rate of the component, as defined by IEC 61508, Part 2
3.1.19
safety instrumented function
SIF
safety function with a specified SIL which is necessary to achieve functional safety and which can be either a
safety instrumented protection function or a safety instrumented control function
3.1.20
safety integrity level
SIL
discrete level (one out of four) for specifying the safety integrity requirements of the SIFs to be allocated to the
SIS. SIL 4 has the highest level of safety integrity; SIL 1 has the lowest
3.1.21
shut-in pressure
SIP
full internal product process pressure that shall be contained by the HIPPS at the seabed when the high-
pressure source is abruptly isolated to protect lower pressure hardware downstream of the spec break
3.1.22
specification (spec) break
point at which equipment pressure rating changes from one RWP rating to a lower one (or vice versa)
downstream
NOTE These locations are defined by the normal operating conditions of a flow stream that allows the use of lower
design pressure equipment.
3.1.23
subsea tieback
an offshore field developed with one or more wells completed on the seafloor, using subsea trees
NOTE The wells are connected by flowlines and umbilicals—the pathways for electrical and hydraulic signals—to a
production facility in another area.
4 © ISO 2011 – All rights reserved

ISO/DIS 13628-14
3.1.24
systems integration test
SIT
a process conducted on land to verify the fit, form, and function between interfaces of all subsea equipment
and associated running tools prior to offshore installation
3.1.25
systematic failure
failure related in a deterministic way to a certain cause, which can only be eliminated by a modification of the
design or of the manufacturing process, operational procedures, documentation, or other relevant factors
3.2 Symbols and abbreviations
C number of anticipated HIPPS final element closures per year
L expected design operating life of the HIPPS final element (years)
MTBF mean time (number of cycles) between failures
PFD average PFD
a
t defined as the planned testing interval of the entire HIPPS (sensors, logic solvers, and final
elements) while in-service to maintain the demonstrated SIL
λ dangerous undetectable failures
du
λ total failure rate
TOT
BSDV boarding shutdown valve
DCS distributed control system
DCV directional control valve
EPU electrical power unit
ESD emergency shutdown
FAT factory acceptance test
FIV flowline isolation valve
FMECA failure mode effects and criticality analysis
GOR gas-oil-ratio
HFT hardware fault tolerance
HIPPS high integrity pressure protection system
HPU hydraulic power unit
HSCM HIPPS subsea control module
LOPA layer of protection analysis
MAOP maximum allowable operating pressure
MAWP maximum allowable working pressure
MCS master control station
MOC management of change
MTBF mean time between failures
MTTF mean time to failure
NDE normally de-energized
NE normally energized
PCS production control system
PE programmable electronics
PES programmable electronic system
PFD probability of failure on demand
PLEM pipeline end manifold
PLET pipeline end termination
PR performance requirement
PSD production shutdown
PSH pressure switch high
PSL product specification level
PST partial stroke testing
PSV process safety valve
QRA quantitative risk analysis
QTC qualification test coupon
ISO/DIS 13628-14
ROT remotely operated tool
ROV remotely operated vehicle
RWP rated working pressure
SAFE safety analysis function evaluation
SCM subsea control module
SCSSV surface controlled subsurface safety valve
SEM subsea electronics module
SFF safe failure fraction
SIF safety instrumented function
SIL safety integrity level
SIP shut-in pressure
SIS safety instrumented system
SIT systems integration test
SRS safety requirement specification
SWL safe working load
TFL through flowline
UPS uninterruptible power supply
USV underwater safety valve
4 General requirements
4.1 Principle
This clause covers system elements that shall be considered when designing a HIPPS. HIPPS is a SIS used
to protect downstream facilities and personnel, and prevent environmental release by containing high-
pressure excursions.
The design and performance of the HIPPS, including all lifecycle activities, should be based on IEC 61511.
Hazard and risk assessments shall be conducted to determine requirements for risk reductions, allocate
safety integrity level (SIL) of the HIPPS, and demonstrate that the risk of overpressure has been adequately
mitigated. Appropriate regulatory agencies should be consulted for additional design and operating
requirements.
A typical HIPPS is shown in Figure 1.
6 © ISO 2011 – All rights reserved

ISO/DIS 13628-14
Figure 1 — Typical Subsea Production HIPPS Valve Diagram

4.1.1 Pressure Source
The overpressure to be mitigated by the HIPPS could originate from a number of sources. Examples include
but are not limited to high reservoir pressures, subsea pumps, and connection to higher pressure pipeline or
any combination thereof.
The source could be gas, liquid, or multiphase fluid, which have different system response requirements. The
flow composition may change during the production life and may be dependent on topography. All of these
aspects, and any uncertainties associated with them, need to be considered as part of a full HIPPS analysis.
Before additional wells are tied into an existing system or any other change is made that could affect fluid
properties, a new flow analysis should be conducted to ensure that the system is designed to cover the new
configuration.
4.1.2 HIPPS
SIS, defined by this document, provides pressure protection to downstream components.
4.1.3 Subsea fortified zone
A fortified section may be located downstream of the HIPPS isolation valves to allow time to respond to the
system closure determined by the pressure transient calculations. The response time to system closure will be
dependent on the nature of the flow for the specific system and would include consideration of the gas-oil-ratio
(GOR).
The pressure rating of the fortified section will be project-specific and will range from the maximum allowable
operating pressure (MAOP) of the flowline/pipeline, to the same as the full rating of the pressure source (e.g.
subsea tree).
ISO/DIS 13628-14
The length of the “fortified” section should be determined based on flow analysis. The use of alternative flow
assurance methods (i.e. chemicals) should not be considered when determining the length of the fortified
section. It is conceivable that this section may not be required, but this shall be proven based on flow analysis.
4.1.4. Unfortified zone (flowline)
The unfortified zone is downstream of the fortified zone and upstream of the host zone. The location of the
unfortified zone shall be determined by the hydraulic analysis and be dependent on the impact of any eventual
leakage risks to be mitigated. The hydraulic analysis should include all potential system transients
(multiphase/slug flow, etc.). The unfortified zone shall be located to minimize risk of injury to people and
damage to infrastructure and the environment. Design should also take into account the need for system
testing.
The unfortified zone would be proven to function by hydraulic analysis, design, and testing as appropriate.
4.1.5 Host fortified zone
The near-platform riser section should be designed such that release of hydrocarbon or hazardous materials
occurs away from the facility to protect personnel. Near-platform riser section refers to a region, which if
breached by high-pressure excursions, could result in damage to the facility or threat to life.
4.1.6 Topsides
A process safety valve (PSV) can be used to relieve build up of pressure due to valve leakage. The PSV
would be l ocated between the flowline isolation valve (FIV) and t he boarding shutdown valve (BSDV).
Consideration needs to be given to safe venting of fluid, particularly during a platform shutdown or unmanned
situation.
4.2 Production characteristics
Design of all product-containing systems shall consider the fluid and gas properties being transported and
select materials and welding processes fully compatible with planned products.
For multiphase production systems, the full range of GOR, water production rates, sand, carbon dioxide,
hydrogen sulfide, injected chemicals, and other products shall be fully investigated during analysis and design.
4.3 Flowline rupture considerations
Design of the flowline downstream of a HIPPS shall consider the possibility of failure of the HIPPS to correctly
function. The design should determine the likely consequences and design mitigations to minimize each
consequence. Some of the key consequences of failure of the HIPPS and possible mitigations to consider
include the following.
− Uncontrolled—In this case, the flowline ruptures and inventory is released to the environment. The system
shall be arranged so that any pipeline burst occurs within the protective segment. Protection of human life is
the highest priority. An environmental remediation plan should be in place.
− Controlled but Uncontained—In this case, there is a pressure-relieving mechanism which minimizes the
quantity of product released. An environmental remediation plan should be in place.
− Controlled and Contained—In this case, there is a pressure-relieving mechanism (preferably self-resetting)
which contains the release. The capacity of the containment system shall be defined.
4.4 Process hazard and risk analysis
The decision to utilize a HIPPS shall be based on a qualitative and quantitative risk analysis (QRA) carried out
in accordance with industry standards. Risk analysis requires determining the frequency of the event
8 © ISO 2011 – All rights reserved

ISO/DIS 13628-14
(overpressure) and the ability of safeguards (HIPPS, etc.) to reduce the consequences, such that the
likelihood of the event becomes tolerable.
A qualitative risk analysis such as process hazard analysis shall be conducted using a defined methodology.
The process hazard is typically overpressure and the subsequent failure of downstream equipment, potentially
resulting in a loss of hydrocarbon containment. The risk is the frequency, or possibility of, overpressuring the
equipment and the resulting consequences of equipment failure.
Quantitative analysis shall be performed [e.g. layer of protection analysis (LOPA)] as defined in IEC 61511.
Risk thresholds shall be those mandated by the regulatory agency or the owner whichever is the most
stringent.
4.5 Selection and determination of SIL
SIL is a representation of the required safety unavailability [average probability of failure on demand (PFD)] of
a safety instrumented function (SIF). The SIL is expressed as a Level 1 through Level 4, which corresponds
with Table 1.
Table 1—SILs
Availability Risk Reduction
SIL PFD
(1-PFD) Factor
SIL 1 0,1 to 0,01 0,90to 0,99 10 to 100
SIL 2 0,01 to 0,001 0,99 to 0,999 100 to 1 000
SIL 3 0,001 to 0,0001 0,999 to 0,9999 1 000 to 10 000
a
SIL 4 0,0001 to 0,00001 0,9999 to 0,99999 10 000 to 100 000
a Not applicable in the process industry.
SILs are determined, either in a pr escriptive manner where a pr eselected SIL may be us ed when the
application meets the required criteria, or a quantitative manner where the required SIL is calculated based on
the risk thresholds, initiating frequencies, and other layers of protection to determine the required SIL of the
HIPPS.
Determination of the HIPPS SIL should consider additional safeguards that are installed:
− pressure switch high (PSH) at facility, upstream of BSDV;
− PSH at each individual pressure source, upstream of HIPPS;
− PSV at facility upstream of the BSDV sized for either leakage rate (partial protection) or full flow rate;
− reinforced section at facility riser.
SIL analysis is primarily conducted for safety; however, additional consideration may be for environmental or
economic impacts. In this case the consideration with the highest SIL requirement may be used as the design
basis.
4.6 Safety requirement specification (SRS)
4.6.1 General
ISO/DIS 13628-14
The SRS is the controlling document for design, validation, and validation of the HIPPS in accordance with the
project requirements and specifications and the basis for HIPPS performance monitoring and followup during
the operating lifetime. The safety requirements specification shall meet the requirements of IEC 61511.
The SRS shall be kept current through management of change (MOC) process from concept development
until the HIPPS is decommissioned.
The SRS shall include the following information or make references to:
a) process description (which includes pressure ratings for all flowline segments) and summary of the
documented hazard scenarios generated from the hazard analysis process;
b) descriptions of functions performed by the SIF (in relationship to the associated hazard scenario) stating the
functional relationship between process inputs and outputs including logic, mathematical functions, and any
required permissives;
c) SIL and PFD for each SIF;
d) HIPPS process measurements together with their normal operating ranges and applicable trip set point
tolerance;
e) safe state of the process for each identified SIF, the sources of demand, and the demand rate;
f) response time requirements for the HIPPS to bring the process to safe state;
g) HIPPS and the requirements for resetting the HIPPS after a trip;
h) requirements for de-energize to trip;
i) requirements for overrides/inhibits/bypasses/manual shutdowns, including how they will be cleared;
j) considerations for process common cause failures such as corrosion, plugging, power supply, etc.;
k) actions to be taken in event of diagnosed dangerous failures;
l) requirements for special start-up and HIPPS restart considerations;
m) interface to other safety and process control systems;
n) requirements for proof testing;
o) required testing frequencies, PFD, and mean time to failure spurious (MTTF spurious); and
p) any additional information as required by the specific design.
4.6.2 HIPPS SIS
The HIPPS SIS shall be an autonomous safety system with a local logic system controlling HIPPS operation
and shall include the following elements:
a) multiple independent pressure sensing devices responding to the pipeline pressure,
b) high integrity logic processing subsystem,
c) redundant barrier isolation valves (final element),
d) HIPPS system reset to prevent automatic reopening of the HIPPS valves after a trip, and
e) communications and additional equipment required for monitoring and testing the system.
10 © ISO 2011 – All rights reserved

ISO/DIS 13628-14
HIPPS SIS subassemblies or components should be optimized for retrievability to support maintenance and
availability requirements.
5 Procedure – Basic design
5.1 Principle - Design basis requirements
5.1.1 Shut-in pressure (SIP)
SIP is the full internal pressure that shall be contained by the HIPPS and upstream piping when the HIPPS
has closed and all other upstream valves are open to the pressure source. Both transient pressure wave
(water hammer effect) and sustained
...