IEC 62381:2024

IEC 62381 ®
Edition 3.0 2024-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Automation systems in the process industry –
Factory acceptance test (FAT), site acceptance test (SAT), and site integration
test (SIT)
Systèmes d'automatisation dans l’industrie de transformation –
Essais d'acceptation en usine (FAT), essais d'acceptation sur site (SAT) et
essais d'intégration sur site (SIT)
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IEC 62381 ®
Edition 3.0 2024-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Automation systems in the process industry –

Factory acceptance test (FAT), site acceptance test (SAT), and site integration

test (SIT)
Systèmes d'automatisation dans l’industrie de transformation –

Essais d'acceptation en usine (FAT), essais d'acceptation sur site (SAT) et

essais d'intégration sur site (SIT)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.040.40 ISBN 978-2-8322-9418-5

– 2 – IEC 62381:2024 © IEC 2024
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
1.1 General applicability . 9
1.2 Exclusions . 9
1.2.1 Prior- and post-test activities . 9
1.2.2 Regulated industries . 9
1.2.3 Safety instrumented systems . 9
1.2.4 Manufacturing execution systems . 9
1.2.5 Advanced process control . 9
1.2.6 Security for industrial automation and control systems . 9
2 Normative references . 10
3 Terms, definitions and abbreviated terms . 10
3.1 Terms and definitions . 10
3.2 Abbreviated terms . 13
4 Overview of automation system testing . 13
4.1 General . 13
4.2 Methods of test performance . 14
4.3 Project design changes . 14
4.4 Adapted procedures in the event of modifications to existing systems . 14
5 Factory acceptance test (FAT) . 15
5.1 General . 15
5.2 Performance . 15
5.3 Pre-FAT activities . 15
5.3.1 General . 15
5.3.2 Vendor tests . 15
5.3.3 Documentation . 15
5.3.4 Test plan . 16
5.3.5 Test schedule . 16
5.4 FAT punch list . 17
5.4.1 General . 17
5.4.2 Correction . 17
5.4.3 Corrections after FAT . 17
5.5 Documentation of FAT . 18
5.5.1 General . 18
5.5.2 FAT report . 18
5.5.3 FAT final documentation . 18
5.6 FAT completion . 18
6 Factory integration test (FIT) . 19
6.1 General . 19
6.2 Performance . 19
6.3 Pre-FIT activities . 19
6.3.1 General . 19
6.3.2 Test plan . 19
6.3.3 Test schedule . 19
6.4 FIT punch list . 20

6.4.1 General . 20
6.4.2 Correction . 20
6.4.3 Correction after FIT . 20
6.5 Documentation of FIT. 21
6.5.1 General . 21
6.5.2 FIT report . 21
6.5.3 FIT final documentation . 21
6.6 FIT completion . 21
7 Site acceptance test (SAT) . 21
7.1 Performance . 21
7.2 Pre-SAT activities . 22
7.2.1 General . 22
7.2.2 Test plan . 22
7.2.3 Test schedule . 23
7.3 SAT punch list . 23
7.3.1 General . 23
7.3.2 Correction . 23
7.3.3 Correction after SAT . 23
7.4 Documentation of SAT . 24
7.4.1 General . 24
7.4.2 SAT report . 24
7.4.3 SAT final documentation . 24
7.5 SAT completion . 24
8 Site integration test (SIT) . 24
8.1 Performance . 24
8.2 Pre-SIT activities . 25
8.2.1 General . 25
8.2.2 Test plan . 25
8.2.3 Test schedule . 25
8.3 SIT punch list . 26
8.3.1 General . 26
8.3.2 Correction . 26
8.3.3 Correction after SIT . 26
8.4 Documentation of SIT . 27
8.4.1 General . 27
8.4.2 SIT report . 27
8.4.3 SIT final documentation . 27
8.5 SIT completion . 27
Annex A (informative) Factory acceptance testing checklist . 28
A.1 General . 28
A.2 Assemble documentation . 28
A.2.1 General . 28
A.2.2 User requirements specification . 28
A.2.3 Functional requirements specification . 28
A.2.4 Information to vendor . 29
A.2.5 Vendor documentation . 29
A.3 Develop a written test plan and specification . 29
A.3.1 General . 29
A.3.2 Documentation . 29

– 4 – IEC 62381:2024 © IEC 2024
A.3.3 Hardware/software inventory . 30
A.3.4 Mechanical inspection . 30
A.3.5 Wiring and termination inspection . 30
A.3.6 Start-up, shut-down and re-start test and general system functions . 30
A.3.7 System alarm test . 31
A.3.8 Hardware redundancy and diagnostics (including fail and changeover of
redundant units) . 31
A.3.9 Operator interface . 31
A.3.10 Engineering workstation functionality . 31
A.3.11 User management . 32
A.3.12 Network and system security . 32
A.3.13 Test I/O to the operator display. 32
A.3.14 Complete I/O tests . 33
A.3.15 Bus interfaces. 33
A.3.16 Intelligent field devices . 33
A.3.17 FAT open item . 33
A.3.18 Test of communication links to subsystems . 34
A.3.19 Application programming . 34
A.3.20 Check of other system functions . 34
A.4 Develop a test schedule . 35
A.5 FAT certificate . 35
Annex B (informative) Site acceptance testing checklist . 36
B.1 General . 36
B.2 Develop a written test plan and specification . 36
B.2.1 General . 36
B.2.2 Documentation . 36
B.2.3 Hardware/software inventory . 36
B.2.4 Mechanical inspection . 36
B.2.5 Wiring and terminal inspection . 37
B.2.6 System energization . 37
B.2.7 Hardware redundancy and diagnostics . 37
B.2.8 Operator interface . 37
B.2.9 Network and system security . 37
B.2.10 I/O test . 37
B.2.11 Bus interfaces. 37
B.2.12 Intelligent field devices . 37
B.2.13 Application programming . 38
B.3 Develop a test schedule . 38
B.4 SAT certificate . 38
Annex C (informative) Site integration testing checklist . 39
C.1 General . 39
C.2 Develop a written test plan and specification . 39
C.2.1 General . 39
C.2.2 Documentation . 39
C.2.3 Visual inspection . 39
C.2.4 Communications . 39
C.2.5 Operator interface . 39
C.2.6 Hardwired I/O . 40
C.2.7 Functionality . 40

C.3 Develop a test schedule . 40
C.4 SIT certificate . 40
Bibliography . 41

Figure 1 – Project phases and E&I testing . 14

Table A.1 – Test schedule . 35
Table B.1 – Test schedule . 38
Table C.1 – Test schedule . 40

– 6 – IEC 62381:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
AUTOMATION SYSTEMS IN THE PROCESS INDUSTRY –
FACTORY ACCEPTANCE TEST (FAT), SITE ACCEPTANCE TEST (SAT),
AND SITE INTEGRATION TEST (SIT)

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
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shall not be held responsible for identifying any or all such patent rights.
IEC 62381 has been prepared by subcommittee 65E: Devices and integration in enterprise
systems, of IEC technical committee 65: Industrial-process measurement, control and
automation. It is an International Standard.
This third edition cancels and replaces the second edition published in 2012. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) General re-organization of the standard;
b) Current technology incorporated;
c) Optional factory integration test (FIT) added;

d) Replaced the forms in the annexes with detailed checklists of activities which can be used
to develop project-specific test plans; and
e) Provided additional references to other applicable standards.
The text of this International Standard is based on the following documents:
Draft Report on voting
65E/1080/FDIS 65E/1092/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
– 8 – IEC 62381:2024 © IEC 2024
INTRODUCTION
There is an increasing trend in the process industry to shorten the time period for project
execution. At the same time, the complexity of automation systems is being increased due to
the number of connected systems and the use of new technologies, for example, wired and
wireless field sensor networks.
Experience has shown that the owner, the buyer and the vendor have long and extensive
discussions to unambiguously establish the scope of activities and responsibilities in order to
achieve timely delivery and acceptance of automation systems.
This document provides requirements and guidance on acceptance testing of control system
installations, which can lead to a mutual understanding about the scope of activities of each
party.
AUTOMATION SYSTEMS IN THE PROCESS INDUSTRY –
FACTORY ACCEPTANCE TEST (FAT), SITE ACCEPTANCE TEST (SAT),
AND SITE INTEGRATION TEST (SIT)

1 Scope
1.1 General applicability
This International Standard defines requirements and checklists for the factory acceptance test
(FAT), the factory integration test (FIT), the site acceptance test (SAT), and the site integration
test (SIT). These tests are carried out to demonstrate that the automation system meets the
requirements of the applicable specification.
This document provides a means for all parties, including the owner, the buyer, and the vendor,
to clearly establish and agree on the scope of activities and responsibilities involved in
performing these tests in order to achieve a timely delivery and acceptance of the automation
system. The activities specified in this document can be used to develop test plans adapted to
the specific requirements of the process/plant/equipment.
The annexes of this document contain checklists which are available for consideration when
preparing specific test procedures and documentation for a specific automation system.
1.2 Exclusions
1.2.1 Prior- and post-test activities
Engineering and manufacturing activities prior to or after the FAT, FIT, SAT and SIT, such as
loop checks and commissioning, are not covered by this document.
1.2.2 Regulated industries
For applications in the pharmaceutical or other highly specialized industries, additional
guidelines (for example, good automated manufacturing practice (GAMP)), definitions and
stipulations apply in accordance with other applicable existing standards.
1.2.3 Safety instrumented systems
The user can utilize this document to develop necessary testing for basic checks of a safety
system, however, this document does not cover validation of a safety system. IEC 61511
provides requirements for checks and validation of safety instrumented systems.
1.2.4 Manufacturing execution systems
Testing and verification of manufacturing execution systems (MES) is not covered by this
document.
1.2.5 Advanced process control
Testing and verification of advanced process control (APC) is not covered by this document.
1.2.6 Security for industrial automation and control systems
Although this document includes a limited number of network checks, it does not cover complete
network and system security. IEC 62443 provides requirements for automation and control
systems cyber security.
– 10 – IEC 62381:2024 © IEC 2024
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 62382, Control systems in the process industry – Electrical and instrumentation loop check
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
advanced process control
APC
several tools and techniques whose common characteristic is taking process automation
beyond the limits of single-loop control
Note 1 to entry: APC includes model-based software that is used to direct the process operation and is commonly
referred to as multivariable predictive control or model predictive control.
3.1.2
automation system
complete system for the monitoring and control of production facilities
Note 1 to entry: An automation system can include a BPCS and can also include a SIS and other subsystems.
3.1.3
basic process control system
BPCS
system which responds to input signals from the process, its associated equipment, other
programmable systems and/or operators and generates output signals causing the process and
its associated equipment to operate in the desired manner but which does not perform any SIF
Note 1 to entry: A BPCS includes all of the devices necessary to ensure that the process operates in the desired
manner.
Note 2 to entry: A BPCS typically can implement various functions such as process control functions, monitoring,
and alarms.
[SOURCE: IEC 61511-1:2016, 3.2.3]
3.1.4
buyer
company purchasing the equipment or control system from the vendor
Note 1 to entry: The buyer can be the owner of the equipment or control system, or the buyer can be another
company.
3.1.5
cold commissioning
phase, during which the activities associated with the testing and operation of equipment or
facilities using test media such as water or inert substances prior to introducing any chemical
in the system take place
3.1.6
control system
system which responds to input signals from the process and/or from an operator and generates
output signals causing the process to operate in the desired manner
Note 1 to entry: The control system includes sensors and final elements and can be either a BPCS or a SIS or a
combination of the two.
[SOURCE: IEC 61511-1:2016, 3.2.10]
3.1.7
detailed design specification
separate document that shows how the system functions and meets the requirements
established in the functional requirements specification
3.1.8
factory acceptance test
FAT
activity, including inspection and testing, to demonstrate that the automation system,
subsystem, or component is in accordance with the specification and is typically conducted at
the vendor's facility
3.1.9
factory integration test
FIT
activity, including inspection and testing, conducted at the vendor's facility to demonstrate that
the merging of some or all of the various subsystems and components into one overall
automation system functions in accordance with the specification
3.1.10
functional requirements specification
FRS
specification listing the detailed operational requirements for a control system (i.e., what the
system does, not how it does it)
3.1.11
hot commissioning
phase during which the activities associated with the testing and operation of equipment or
facilities using the actual chemical process prior to making an actual production run take place
3.1.12
manufacturing execution system
MES
computerized system used in manufacturing to track and document the transformation of raw
materials to finished goods
3.1.13
owner
company that operates the production facilities where the automation system is or will be
installed
– 12 – IEC 62381:2024 © IEC 2024
3.1.14
precommissioning
phase during which the activities of non-operating adjustments, cold alignment checks,
cleaning, and testing of machinery take place
3.1.15
process industry
industry that has a continuous or batch flow and uses chemical reactions, separations, or mixing
techniques in order to create new products, modify existing products or treat waste, and
includes the following types of industries: chemical, petrochemical, water and wastewater
treatment, paper, cement, etc.
Note 1 to entry: Process industry does not include such industries as equipment/machine manufacturing or other
similar industries. It does not include industries which are subject to regulations which have specialized validation
requirements.
3.1.16
punch list
list of all problems found, the corrective action to be taken, party responsible and date
completed
Note 1 to entry: Other information categories can be added as required.
3.1.17
safety instrumented function
SIF
safety function to be implemented by a safety instrumented system (SIS)
[SOURCE: IEC 61511-1:2016, 3.2.66]
3.1.18
safety instrumented system
SIS
instrumented system used to implement one or more SIFs
Note 1 to entry: A SIS is composed of any combination of sensor(s), logic solver(s), and final element(s) (e.g., see
Figure 6 of IEC 61511:2016). It also includes communication and ancillary equipment (e.g., cables, tubing, power
supply, impulse lines, heat tracing).
Note 2 to entry: A SIS can include software.
Note 3 to entry: A SIS can include human action as part of a SIF.
[SOURCE: IEC 61511-1:2016, 3.2.67, modified – Figure 6 and reference to ISA
TR84.00.04:2015 part 1 have been omitted.]
3.1.19
site acceptance test
SAT
activity, including inspection and testing, conducted at the site of the installation, to demonstrate
that the installation of the automation system, any subsystem, or any component is in
accordance with the applicable standards, codes, specifications, and installation instructions
3.1.20
site integration test
SIT
activity, including inspection and testing, conducted at the site of the installation, to demonstrate
that the merging of the various subsystems and components into one overall automation system
is completed and that all components work together in accordance with the specification

3.1.21
tag
unique identifier assigned to a process measurement, calculation, or device within the
automation system
3.1.22
user requirements specification
URS
document that defines the user's (owner's) requirements for the automation system
3.1.23
vendor
manufacturer, distributor, or systems integrator of the automation system, subsystem, or
component
3.2 Abbreviated terms
The following abbreviated terms are used (for terms not otherwise defined in this Clause 3):
DCS Distributed control system
E&I Electrical and instrumentation
ERP Enterprise resource planning
HMI Human machine interface
I/O Input and output
P&ID Piping (or process) and instrumentation diagram
PLC Programmable logic controller
UPS Uninterruptible power supply
4 Overview of automation system testing
4.1 General
An automation system is to be tested at various stages in its development and implementation.
Each new automation system shall be subjected to three tests to demonstrate proper operation
in accordance with project-specific requirements: factory acceptance test (FAT), site
acceptance test (SAT) and site integration test (SIT). Loop tests shall be performed in
accordance with IEC 62382, which typically occur after SIT. All these tests shall be completed,
with any open items documented and agreed upon by all parties involved in the tests, prior to
the system being placed in operation. An optional fourth test, factory integration test (FIT) can
also be performed on all or part of the system while at the vendor's factory.
The typical order of execution of these tests is:
• The factory acceptance test (FAT) is performed on the automation system, subsystem or
component before it leaves the vendor's factory to demonstrate that it functions in
accordance with the project-specific requirements.
• The factory integration test (FIT) is a fourth, optional testing point to demonstrate that the
merging of some or all the various subsystems and components function as specified. This
test is performed after or in conjunction with the FAT, before the automation system,
subsystem or component leaves the vendor's factory.
• The site acceptance test (SAT) is performed after installation on site to demonstrate the
automation system, subsystem, or component is in accordance with the applicable
standards, codes, specifications, and installation instructions. This test is performed after
each subsystem is installed.
– 14 – IEC 62381:2024 © IEC 2024
• The site integration test (SIT) is performed after the SAT to demonstrate that the merging
of the various subsystems and components into one overall automation system is complete
and that all subsystems and components work together as specified in the test plan. This
test can be performed on two or more subsystems or components after each has been
installed and successfully completed a SAT or after all subsystems and components have
been installed and successfully completed a SAT.
Figure 1 provides a general illustration of a portion of the timeline of a project from construction
to production and when the above tests occur. The industry and the specifics of a project can
vary the relative timing of each test.

Figure 1 – Project phases and E&I testing
4.2 Methods of test performance
This document provides checklists for developing test plans for the automation system.
Traditionally, these tests are performed using manual methods. With modern systems, these
tests can also be performed using automated methods, depending on the system's capability.
If automated methods are used, it is the vendor's responsibility to demonstrate that the
automated tests completely cover all aspects of the test plan and are validated.
4.3 Project design changes
Changes made to the project design during or at any time after FAT, whether to the detailed
design scope or as a correction/adjustment made during testing, s
...