EN ISO 20815:2010

SLOVENSKI STANDARD
01-maj-2010
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SIST EN ISO 20815:2008
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Petroleum, petrochemical and natural gas industries - Production assurance and
reliability management (ISO 20815:2008, Corrected version 2009-06-15)
Erdöl- und Erdgasindustrie - Betriebsoptimierung und Zuverlässigkeitsmanagement (ISO
20815:2008, korrigierte Fassung 2009-06-15)
Industries du pétrole, de la pétrochimie et du gaz naturel - Assurance de la production et
management de la fiabilité (ISO 20815:2008, Version corrigée 2009-06-15)
Ta slovenski standard je istoveten z: EN ISO 20815:2010
ICS:
75.180.01 Oprema za industrijo nafte in Equipment for petroleum and
zemeljskega plina na splošno natural gas industries in
general
75.200 2SUHPD]DVNODGLãþHQMH Petroleum products and
QDIWHQDIWQLKSURL]YRGRYLQ natural gas handling
]HPHOMVNHJDSOLQD equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 20815
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2010
ICS 75.180.01; 75.200 Supersedes EN ISO 20815:2008
English Version
Petroleum, petrochemical and natural gas industries -
Production assurance and reliability management (ISO
20815:2008, Corrected version 2009-06-15)
Industries du pétrole, de la pétrochimie et du gaz naturel - Erdöl-, petrochemische und Erdgasindustrie -
Assurance de la production et management de la fiabilité Betriebsoptimierung und Zuverlässigkeitsmanagement
(ISO 20815:2008, Version corrigée 2009-06-15) (ISO 20815:2008, korrigierte Fassung 2009-06-15)
This European Standard was approved by CEN on 16 February 2010.

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. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN 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 CEN member into its own language and notified to the CEN 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.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 20815:2010: E
worldwide for CEN national Members.

Contents Page
Foreword .3

Foreword
The text of ISO 20815:2008, Corrected version 2009-06-15 has been prepared by Technical Committee
ISO/TC 67 “Materials, equipment and offshore structures for petroleum, petrochemical and natural gas
industries” of the International Organization for Standardization (ISO) and has been taken over as EN ISO
20815:2010 by 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 European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by September 2010, and conflicting national standards shall be
withdrawn at the latest by September 2010.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 20815:2008.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: 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 the United Kingdom.
Endorsement notice
The text of ISO 20815:2008, Corrected version 2009-06-15 has been approved by CEN as a EN ISO
20815:2010 without any modification.

INTERNATIONAL ISO
STANDARD 20815
First edition
2008-06-01
Corrected version
2009-06-15
Petroleum, petrochemical and natural gas
industries — Production assurance and
reliability management
Industries du pétrole, de la pétrochimie et du gaz naturel — Assurance
de la production et management de la fiabilité

Reference number
ISO 20815:2008(E)
©
ISO 2008
ISO 20815:2008(E)
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ii © ISO 2008 – All rights reserved

ISO 20815:2008(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviated terms . 2
3.1 Terms and definitions. 2
3.2 Abbreviations . 7
4 Production assurance and decision support . 8
4.1 Framework conditions. 8
4.2 Optimization process . 9
4.3 Production-assurance programme . 11
4.4 Alternative standards . 15
5 Production-assurance processes and activities . 15
Annex A (informative) Contents of production-assurance programme (PAP) . 17
Annex B (informative) Core production-assurance processes and activities . 19
Annex C (informative) Interacting production-assurance processes and activities. 26
Annex D (informative) Production-performance analyses. 30
Annex E (informative) Reliability and production-performance data . 34
Annex F (informative) Performance objectives and requirements . 36
Annex G (informative) Performance measures for production availability. 38
Annex H (informative) Catastrophic events. 47
Annex I (informative) Outline of techniques. 49
Bibliography . 64

ISO 20815:2008(E)
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 20815 was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore structures
for petroleum, petrochemical and natural gas industries.
This corrected version of ISO 20815:2008 incorporates the following corrections:
⎯ 3.1.13 “(t + ∆t)” modified to “[t, (t + ∆t)]”;
⎯ 3.1.46, Equation (1) symbols and definitions modified;
⎯ Clause G.2, Equation (G.2) symbols and definitions modified.

iv © ISO 2008 – All rights reserved

ISO 20815:2008(E)
Introduction
The petroleum and natural gas industries involve large capital investment costs as well as operational
expenditures. The profitability of these industries is dependent upon the reliability, availability and
maintainability of the systems and components that are used. Therefore, for optimal production availability in
the oil and gas business, a standardized, integrated reliability approach is required.
The concept of production assurance, introduced in this International Standard, enables a common
understanding with respect to use of reliability technology in the various life-cycle phases and covers the
activities implemented to achieve and maintain a performance level that is at its optimum in terms of the
overall economy and, at the same time, consistent with applicable regulatory and framework conditions.
Annexes A through I are for information only.

INTERNATIONAL STANDARD ISO 20815:2008(E)

Petroleum, petrochemical and natural gas industries —
Production assurance and reliability management
1 Scope
This International Standard introduces the concept of production assurance within the systems and operations
associated with exploration drilling, exploitation, processing and transport of petroleum, petrochemical and
natural gas resources. This International Standard covers upstream (including subsea), midstream and
downstream facilities and activities. It focuses on production assurance of oil and gas production, processing
and associated activities and covers the analysis of reliability and maintenance of the components.
It provides processes and activities, requirements and guidelines for systematic management, effective
planning, execution and use of production assurance and reliability technology. This is to achieve cost-
effective solutions over the life cycle of an asset-development project structured around the following main
elements:
⎯ production-assurance management for optimum economy of the facility through all of its life-cycle phases,
while also considering constraints arising from health, safety, environment, quality and human factors;
⎯ planning, execution and implementation of reliability technology;
⎯ application of reliability and maintenance data;
⎯ reliability-based design and operation improvement.
For standards on equipment reliability and maintenance performance in general, see the IEC 60300-3 series.
This International Standard designates 12 processes, of which seven are defined as core production-
assurance processes and addressed in this International Standard. The remaining five processes are denoted
as interacting processes and are outside the scope of this International Standard. The interaction of the core
production-assurance processes with these interacting processes, however, is within the scope of this
International Standard as the information flow to and from these latter processes is required to ensure that
production-assurance requirements can be fulfilled.
This International Standard recommends that the listed processes and activities be initiated only if they can be
considered to add value.
The only requirements mandated by this International Standard are the establishment and execution of the
production-assurance programme (PAP).
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.
ISO 14224:2006, Petroleum, petrochemical and natural gas industries — Collection and exchange of reliability
and maintenance data for equipment
ISO 20815:2008(E)
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1.1
availability
ability of an item to be in a state to perform a required function under given conditions at a given instant of
time, or in average over a given time interval, assuming that the required external resources are provided
See Figure G.1 for further information.
3.1.2
common cause failure
failures of different items resulting from the same direct cause, occurring within a relatively short time, where
these failures are not consequences of each other
3.1.3
corrective maintenance
maintenance that is carried out after a fault recognition and intended to put an item into a state in which it can
perform a required function
[2]
See IEC 60050-191:1990, Figure 191-10 , for more specific information.
3.1.4
deliverability
ratio of deliveries to planned deliveries over a specified period of time, when the effect of compensating
elements, such as substitution from other producers and downstream buffer storage, is included
See Figure G.1 for further information.
3.1.5
design life
planned usage time for the total system
NOTE Design life should not be confused with MTTF (3.1.25), which is comprised of several items that may be
allowed to fail within the design life of the system as long as repair or replacement is feasible.
3.1.6
down state
internal disabled state of an item characterized either by a fault or by a possible inability to perform a required
[2]
function during preventive maintenance
NOTE This state is related to availability performance.
3.1.7
downtime
[2]
time interval during which an item is in a non-working state
NOTE The downtime includes all the delays between the item failure and the restoration of its service. Downtime can
be either planned or unplanned.
3.1.8
downstream
business process, most commonly in the petroleum industry, associated with post-production activities
EXAMPLES Refining, transportation and marketing of petroleum products.
2 © ISO 2008 – All rights reserved

ISO 20815:2008(E)
3.1.9
failure
termination of the ability of an item to perform a required function
NOTE 1 After failure, the item has a fault.
NOTE 2 “Failure” is an event, as distinguished from “fault”, which is a state.
3.1.10
failure cause
root cause
[2]
circumstances during design, manufacture or use that have led to a failure
NOTE Generic failure cause codes applicable for equipment failures are defined in ISO 14224:2006, B.2.3.
3.1.11
failure data
data characterizing the occurrence of a failure event
3.1.12
failure mode
effect by which a failure is observed on the failed item
NOTE Failure-mode codes are defined for some equipment classes in ISO 14224:2006, B.2.6.
3.1.13
failure rate
limit, if this exists, of the ratio of the conditional probability that the instant of time, T, of a failure of an item falls
within a given time interval, [t, (t + ∆t)] and the length of this interval, ∆t, when ∆t tends to zero, given that the
item is in an up state at the beginning of the time interval
See ISO 14224:2006, Clause C.3 for further explanation of the failure rate.
NOTE 1 In this definition, t may also denote the time to failure or the time to first failure.
NOTE 2 A practical interpretation of failure rate is the number of failures relative to the corresponding operational time.
In some cases, time can be replaced by units of use. In most cases, the reciprocal of MTTF (3.1.25) can be used as the
predictor for the failure rate, i.e. the average number of failures per unit of time in the long run if the units are replaced by
an identical unit at failure.
NOTE 3 The failure rate can be based on operational time or calendar time.
3.1.14
fault
state of an item characterized by inability to perform a required function, excluding the inability during
[2]
preventive maintenance or other planned actions, or due to lack of external resources
NOTE A fault is often a result of a failure of the item itself but the state can exist without a failure.
3.1.15
fault tolerance
attribute of an item that makes it able to perform a required function in the presence of certain given sub-item
[2]
faults
3.1.16
item
any part, component, device, subsystem, functional unit, equipment or system that can be individually
[2]
considered
ISO 20815:2008(E)
3.1.17
logistic delay
accumulated time during which maintenance cannot be carried out due to the necessity to acquire
[29]
maintenance resources, excluding any administrative delay
NOTE Logistic delays can be due to, for example, travelling to unattended installations; pending arrival of spare parts,
specialist, test equipment and information; or delays due to unsuitable environmental conditions (e.g. waiting on weather).
3.1.18
lost revenue
LOSTREV
total cost of lost or deferred production due to downtime
3.1.19
maintainable item
item that constitutes a part, or an assembly of parts, that is normally the lowest level in the equipment
hierarchy during maintenance
See ISO 14224:2006, Annex A, for examples of maintainable items for a variety of equipment.
3.1.20
maintenance
combination of all technical and administrative actions, including supervisory actions, intended to retain an
[2]
item in, or restore it to, a state in which it can perform a required function
3.1.21
maintenance data
data characterizing the maintenance action planned or done
3.1.22
maintainability
〈general〉 ability of an item under given conditions of use, to be retained in, or restored to, a state in which it
can perform a required function, when maintenance is performed under given conditions and using stated
[2]
procedures and resources
See Figure G.1 for further information.
3.1.23
maintenance support performance
ability of a maintenance organization, under given conditions, to provide upon demand, the resources required
[2]
to maintain an item, under a given maintenance policy
NOTE The given conditions are related to the item itself and to the conditions under which the item is used and
maintained.
3.1.24
mean time between failures
MTBF
[2]
expectation of the time between failures
NOTE The MTBF of an item can be longer or shorter than the design life of the system.
3.1.25
mean time to failure
MTTF
[2]
expectation of the time to failure
NOTE The MTTF of an item can be longer or shorter than the design life of the system.
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ISO 20815:2008(E)
3.1.26
mean time to repair
MTTR
[2]
expectation of the time to restoration
3.1.27
midstream
business category involving the processing, storage and transportation sectors of the petroleum industry
EXAMPLES Transportation pipelines, terminals, gas processing and treatment, LNG, LPG and GTL.
3.1.28
modification
[2]
combination of all technical and administrative actions intended to change an item
3.1.29
observation period
time period during which production performance and reliability data are recorded
3.1.30
operating state
[2]
state when an item is performing a required function
3.1.31
operating time
[2]
time interval during which an item is in an operating state
3.1.32
performance objectives
indicative level for the desired performance
NOTE Objectives are expressed in qualitative or quantitative terms. Objectives are not absolute requirements and
may be modified based on cost or technical constraints.
3.1.33
performance requirements
required minimum level for the performance of a system
NOTE Requirements are normally quantitative but may also be qualitative.
3.1.34
petrochemicals
business category producing the chemicals derived from petroleum and used as feedstock for the
manufacture of a variety of plastics and other related products
EXAMPLES Methanol, polypropylene.
3.1.35
preventive maintenance
maintenance carried out at predetermined intervals or according to prescribed criteria and intended to reduce
[2]
the probability of failure or the degradation of the functioning of an item
3.1.36
production-performance analysis
systematic evaluations and calculations carried out to assess the production performance of a system
NOTE The term should be used primarily for analysis of total systems, but may also be used for analysis of
production unavailability of a partial system.
ISO 20815:2008(E)
3.1.37
production assurance
activities implemented to achieve and maintain a performance that is at its optimum in terms of the overall
economy and at the same time consistent with applicable framework conditions
3.1.38
production availability
ratio of production to planned production, or any other reference level, over a specified period of time
NOTE This measure is used in connection with analysis of delimited systems without compensating elements such
as substitution from other producers and downstream buffer storage. Battery limits need to be defined in each case.
See Figure G.1 for further information.
3.1.39
production performance
capacity of a system to meet demand for deliveries or performance
NOTE 1 Production availability, deliverability or other appropriate measures can be used to express production
performance.
NOTE 2 The use of production-performance terms should specify whether it represents a predicted or historic
production performance.
3.1.40
redundancy
[2]
existence of more than one means for performing a required function
3.1.41
reliability
[2]
ability of an item to perform a required function under given conditions for a given time interval
NOTE 1 The term “reliability” is also used as a measure of reliability performance and may also be expressed as a
probability.
NOTE 2 See Figure G.1 for further information.
3.1.42
reliability data
data for reliability, maintainability and maintenance support performance
NOTE Reliability and maintainability (RM) data is the term applied by ISO 14224:2006.
3.1.43
required function
[2]
function, or combination of functions, of an item that is considered necessary to provide a given service
3.1.44
risk
[20]
combination of the probability of an event and the consequences of the event
3.1.45
risk register
tool to log, follow up and close out relevant risks
NOTE Each entry in the risk register should typically include
⎯ description of the risk,
⎯ description of the action(s),
6 © ISO 2008 – All rights reserved

ISO 20815:2008(E)
⎯ responsible party,
⎯ due date,
⎯ action status.
3.1.46
survival probability
R(t)
likelihood of the continued functioning of an item, as given by Equation (1):
RtT=>Pr t (1)
() ( )
where Pr is the probability that T, the time to failure of an item, is greater than t, a time equal to or greater
than 0
3.1.47
up state
state of an item characterized by the fact it can perform a required function, assuming that the external
[2]
resources, if required, are provided
NOTE This relates to availability performance.
3.1.48
upstream
business category of the petroleum industry involving exploration and production
EXAMPLES Offshore oil/gas production facility, drilling rig, intervention vessel.
3.1.49
uptime
[2]
time interval during which an item is in the up state
3.1.50
variability
variations in performance measures for different time periods under defined framework conditions
NOTE The variations can be a result of the downtime pattern for equipment and systems or operating factors, such
as wind, waves and access to certain repair resources.
3.2 Abbreviations
BOP blowout preventer
CAPEX capital expenditures
ESD emergency shut down
FMEA failure modes and effects analysis
FMECA failure modes, effects and criticality analysis
FNA flow-network analysis
FTA fault-tree analysis
GTL gas to liquid
HAZID hazard identification
ISO 20815:2008(E)
HAZOP hazard and operability study
HSE health, safety, environment
LCC life-cycle cost
LNG liquefied natural gases
LOSTREV lost revenue
LPG liquefied petroleum gases
MPA Markov process analysis
MTBF mean time between failure
MTTF mean time to failure
MTTR mean time to repair
OPEX operational expenditure
PAP production-assurance programme
PNA petri net analysis
POR performance and operability review
RBD reliability block diagram
RBI risk-based inspection
RCM reliability-centred maintenance
ROV remote operated vehicle
SIMOPS simultaneous operations
SRA structural-reliability analysis
QA quality assurance
4 Production assurance and decision support
4.1 Framework conditions
The objective associated with systematic production assurance is to contribute to the alignment of design and
operational decisions with corporate business objectives.
In order to fulfil this objective, technical and operational measures as indicated in Figure 1 may be used during
design or operation to change the production performance. Figure 1 shows 21 factors that to a greater or
lesser degree can have an effect on production performance. Some of these factors are purely technical and it
is necessary that they be adhered to in design; others are related purely to operation. Most of the factors have
both technical and operational aspects, e.g. a bypass cannot be used in the operational phase unless
provisions have been made for it in the design phase. In addition, there are dependencies between many of
the listed factors.
8 © ISO 2008 – All rights reserved

ISO 20815:2008(E)
This imposes two important recommendations for production assurance to be efficient.
⎯ Production assurance should be carried out throughout all project design and operational phases.
⎯ Production assurance should have a broad coverage of project activities.

Figure 1 — Design and operational measures that affect production performance
4.2 Optimization process
The main principle for optimization of design or selection between alternative design solutions is economic
optimization within given constraints and framework conditions. The achievement of high performance is of
limited importance unless the associated costs are considered. This International Standard can, therefore, be
considered together with ISO 15663 (all parts).
Examples of constraints and framework conditions that affect the optimization process are
⎯ statutory health, safety and environmental regulations;
⎯ requirements for safety equipment resulting from the risk analysis and the overall safety acceptance
criteria;
⎯ requirements to design or operation given by statutory and other regulatory bodies' regulations;
⎯ project constraints, such as budget, implementation time, national and international agreements;
⎯ conditions in the sales contracts;
⎯ technical constraints.
ISO 20815:2008(E)
The optimization process can be seen as a series of steps as follows (see Figure 2 for an illustration).
a) Assess the project requirements and generate designs that are capable of meeting the project
requirements.
b) Identify all statutory, regulatory and other framework requirements that apply to the project.
c) Predict the appropriate production-assurance parameters.
d) Identify the preferred design solution based on an economical evaluation/analysis, such as net present
value analysis or another optimization criterion.
e) Apply the optimization process as illustrated in Figure 2. Be aware that the execution of the optimization
process requires that the production assurance and reliability function be addressed by qualified team
members.
f) If required, the process can be iterative, where the selected alternative is further refined and alternative
solutions identified. The iterative process is typical for “gated” or threshold project-execution phases.
g) Sensitivity analyses may be performed to take account of uncertainty in important input parameters.
10 © ISO 2008 – All rights reserved

ISO 20815:2008(E)
a
Typical project constraints include HSE requirements; technical feasibility; compliance with acts, rules and regulations;
economical constraints; schedule constraints.
Figure 2 — Optimization process
4.3 Production-assurance programme
4.3.1 Objectives
A production-assurance programme (PAP) shall serve as a management tool in the process of complying with
this International Standard. It may be either a document established for the various life-cycle phases of a new
asset-development project or a document established for assets already in operation. As production
assurance is a continuous activity throughout all life-cycle phases, it shall be updated as and when required. It
may contain the following:
⎯ systematic planning of production-assurance work within the scope of the programme;
⎯ definition of optimization criteria;
ISO 20815:2008(E)
⎯ definition of performance objectives and requirements, if any;
⎯ description of the production-assurance activities necessary to fulfil the objectives, how they are carried
out, by whom and when;
⎯ statements and considerations on interfaces of production assurance and reliability with other activities;
⎯ methods for verification and validation;
⎯ a level of detail that facilitates easy updating and overall coordination.
Annex A of this International Standard suggests a model for the production-assurance programme (PAP)
contents.
The PAP is the only mandatory deliverable from this International Standard.
The life-cycle phases indicated in Table 2 apply for a typical asset-development project. If the phases in a
specific project differ from those below, the activities should be defined and applied as appropriate.
Major modifications may be considered as a project with phases similar to those of an asset-development
project. The requirements to production-assurance activities as given for the relevant life-cycle phases apply.
4.3.2 Project risk categorization
It is necessary to define the level of effort to invest in a production-assurance program to meet the business
objectives for each life-cycle phase. In practice, the production-assurance effort required is closely related to
the level of technical risk in a project. It is, therefore, recommended that one of the first tasks to be performed
is an initial categorization of the technical risks in a project. This enables project managers to make a general
assessment of the level of investment in reliability resources that may have to be made in a project.
The project risk categorization typically varies depending on a number of factors such as financial situation,
risk attitude, etc. Hence, specific risk categorization schemes may be established. However, to provide some
guidance on the process, a simple risk categorization scheme is outlined below.
Projects can be divided into three risk classes:
⎯ high risk;
⎯ medium risk;
⎯ low risk.
The features that describe the three risk classes are further outlined in Table 1. Typically, there is a gradual
transition from one risk class to another. Hence, a certain degree of subjective assessment is required.
However, the justification for the selected risk class for a project should be included in the production-
assurance programme issued during the feasibility or concept phase.
The project risk categorization (high, medium and low) is further applied in Table 2 (see 4.3.3) to indicate what
processes should be performed for the different project categories.

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ISO 20815:2008(E)
Table 1 — Project risk categorization
a
Technology Operating Technical Organizational Description
Risk class
envelope system scale scale and
and complexity complexity
Mature Typical Small scale, low Small and Low Low-budget, low-risk project
technology operating complexity, consistent using field-proven equipment in
conditions minimal change organization, low the same configuration and with
of system complexity the same team under operating
configuration condition similar to previous
projects.
Mature Typical Moderate scale Small to medium Low or Low- to moderate-risk project
technology operating and complexity organization, medium using field-proven equipment in
conditions moderate an operating envelope similar to
complexity previous projects but with some
system and organizational
complexity.
Medium or
Novel or non- New, Large scale, high Large organization, Moderate- to high-risk project
b
mature extended or complexity high complexity high using either novel or non-mature
technology for aggressive equipment or with new or
a new or operating extended operating conditions.
extended environment Project involves large, complex
operating systems and management
environment organizations.
a
The term “low or medium” indicates that projects comprising the indicated features can be classified as either low-risk or medium-
risk projects, likewise for the term “medium or high”.
b
The novel or non-mature technology should have a potential significant impact on the project outcome to be classified as high-risk.

4.3.3 Programme activities
Production-assurance activities should be carried out in all phases of the life cycle of facilities to provide input
to decisions regarding feasibility, concept, design, manufacturing, construction, installation, operation,
maintenance and modification. Processes and activities shall be initiated only if they are considered to
contribute to added value of the project.
The production-assurance activities specified in the PAP shall be defined in view of the actual needs,
available personnel resources, budget framework, interfaces, milestones and access to data and general
information. This is necessary to reach a sound balance between the cost and benefit of the activity.
Production assurance should consider organizational and human factors as well as technical aspects.
Important tasks of production assurance are to monitor the overall performance level, manage reliability and
the continuous identification of the need for production-assurance activities. A further objective of production
assurance is to contribute technical, operational or organizational recommendations.
The processes and activities specified in the PAP shall focus on the main technical risk items initially identified
through a top-down screening process (see 4.3.2). A risk-classification activity can assist in identifying
performance-critical systems that should be subject to more detailed analysis and follow-up.
The emphasis of the production-assurance activities changes for the various life-cycle phases. Early activities
should focus on optimization of the overall configuration, while attention to critical detail increases in the later
phases.
In the feasibility and concept phases, the field layout configuration should be identified. This also includes
defining the degree of redundancy (fault tolerance), overcapacity and flexibility, on a system level. This
requires establishing the CAPEX, OPEX, LOSTREV, expected cost or benefit of risks and revenue for each
alternative.
These financial values are, in turn, fed back into the operators’ profitability tools, for evaluation of profitability
and selection of the alternative that best fits with the attitude towards risk. Optimal production availability for
field layouts requires that overemphasis on CAPEX is avoided, and it is recommended that this be achieved
ISO 20815:2008(E)
through long-term partnering between suppliers and operators, as well as between suppliers and their sub-
suppliers. Such long-term relationships ensure mutual confidence and maturing of the technology. Early direct
involvement of the above parties with focus on the overall revenue in a life-cycle perspective is advised. This
means, for example, implementing the resulting recommendations as specifications in the invitations to tender.
An overview of the production-assurance processes is given in Table 2 and Clause 5, while descriptions of the
recommended activities for the processes are given in Annex B and Annex C.
The production-assurance processes defined in this International Standard are divided into two main classes:
core processes and interacting processes. The main reason for this split is to indicate for which processes a
potential production-assurance discipline is normally responsible and for which processes other disciplines
(e.g. project management, QA, etc.) are normally responsible. However, all processes can be equally
important to ensure success.
Table 2 provides recommendations (indicated by an “X”) on which processes should be performed as a
function of the project risk categorization (see 4.3.2). The table also provides recommendations (indicated by
an “X”) as to when the processes should be applied (in what life-cycle phase).
Production-assurance requirements (process 1) can be used to illustrate the interpretation of the table. This
process, which is further described in Annex B, should be implemented for medium- and high-risk projects,
and performed in the feasibility, concept design, engineering and procurement life-cycle phases.
Table 2 — Overview of production-assurance processes versus risk levels and life-cycle phases
Life-cycle phase
Pre-
Production-assurance processes for asset development
contract Post-contract award
award
c
Process name and number
— X X 1. Production-assurance requirements X X X X — — —
X X X 2. Production-assurance planning X X X X X X x
— X X 3. Design and manufacture for production assurance — X X — X X X
X X X 4. Production assurance X X X X X X X
— X X 5. Risk and reliability analysis X X X — — — —
X X X 6. Verification and validation X X X — — — —
X X X 7. Project risk management X X X X X X X
— — X 8. Qualification and testing X X X X
X X X 9. Performance data tracking and analysis — — — — — X X
— — X 10. Supply-chain management — — — X — — —
X X X 11. Management of change — X X X X X X
X X X 12. Organizational learning X X X X X X X
a
Including front-end engineering and design (FEED).
b
Including pre-engineering and detailed engineering.
c
The following production-assurance processes are within the main scope of work for this International Standard: 1, 2, 3, 4, 5,
6 and 9.
NOTE It should be noted that a process can be applicable for a certain risk class or life-cycle phase although no “X” is indicated
in this table. Likewise, if it can be argued that a certain process does not add value to a project, it may be omitted.
14 © ISO 2008 – All rights reserved

Low-risk projects
Medium-risk projects
High-risk projects
Feasibility
a
Conceptual design
b
Engineering
Procurement
Fabrication/Assembly/Testing
Installation and commissioning
Operation
SIST E
...