IEC TR 62918:2014

IEC TR 62918 ®
Edition 1.0 2014-07
TECHNICAL
REPORT
colour
inside
Nuclear power plants – Instrumentation and control important to safety –
Use and selection of wireless devices to be integrated in systems
important to safety
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IEC TR 62918 ®
Edition 1.0 2014-07
TECHNICAL
REPORT
colour
inside
Nuclear power plants – Instrumentation and control important to safety –

Use and selection of wireless devices to be integrated in systems

important to safety
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XB
ICS 27.120.20 ISBN 978-2-8322-1750-4

– 2 – IEC 62918:2014  IEC 2014
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 9
4 Motivation . 11
5 Generic applications . 13
6 Technology . 16
6.1 Wireless basics . 16
6.2 Industrial wireless sensor networks . 19
6.3 Radio frequency . 20
6.3.1 Applications . 20
6.3.2 802.11 (Wi-Fi), 802.15.1 (Bluetooth), 802.15.4 (sensors) . 23
6.4 Satellite leased channels and VSAT . 25
6.5 Magnetic field communications . 26
6.6 Visual light communication (VLC) . 27
6.7 Acoustic communication. 27
6.8 Asset tracking utilizing IEEE 802.11 – Focus on received signal strength . 28
6.9 Asset tracking (RFID/RTLS): ISO 24730 . 29
7 Current wireless technology implementations . 30
7.1 General . 30
7.2 Comanche Peak nuclear generating station . 30
7.3 Arkansas Nuclear One (ANO) nuclear power plant . 31
7.4 Diablo Canyon nuclear power plant . 32
7.5 Farley nuclear power plant . 33
7.6 San Onofre nuclear generating station . 33
7.7 South Texas project electric generating station . 34
7.8 High Flux Isotope Reactor (HFIR), Oak Ridge, TN . 34
8 Considerations . 36
8.1 General . 36
8.2 Concerns regarding wireless technology . 36
8.3 Wireless deployment challenges . 37
8.4 Coexistence of 802.11 and 802.15.4 . 38
8.5 Signal propagation . 40
8.6 Lessons learned from wireless implementations . 41
8.6.1 General . 41
8.6.2 Comanche Peak implementation . 41
9 Concerns . 42
9.1 Common reliability and security concerns for wired media and wireless
media. 42
9.2 Reliability and security concerns that are more of an issue for wired systems . 42
9.3 Reliability and security concerns that are more of an issue for wireless
systems . 42
10 Standards . 43
10.1 Nuclear standards . 43

IEC 62918:2014  IEC 2014 – 3 –
10.1.1 General . 43
10.1.2 IEEE Std. 603-1998 . 43
10.1.3 IEEE Std. 7-4.3.2-2003 . 44
10.1.4 IEC 61500 . 44
10.2 Other safety-related standards and guidelines . 45
10.2.1 IEC 61784-3 . 45
10.2.2 VTT research notes 2265. 46
10.2.3 European Workshop on Industrial Computer Systems – Technical
Committee 7 (EWICS TC7) . 47
11 Conclusions . 47
11.1 Issues for wireless application to NPP . 47
11.2 Recommendations . 48
Annex A (informative) Use of 5 GHz in the world . 50
Annex B (informative) Synopses of wireless technologies . 51
B.1 802.11 . 51
B.2 ISO 14443 Near Field Communications (NFC) . 56
B.3 Real details of mesh networking . 59
B.4 Not all mesh networks are created equal – Latency and indeterminism in
mesh networks . 62
B.5 ISA100.11a – “Mesh – When You Need It – Networking” . 63
B.6 Security by non-routing edge nodes . 66
B.7 Device and network provisioning methods . 67
Bibliography . 69

Figure 1 – Cost comparison – Wired versus wireless for an extensive building
automation system . 12
Figure 2 – Wireless use in nuclear power plants . 12
Figure 3 – Possible application areas for wireless instrumentation in a nuclear power
plant . 13
Figure 4 – Bandwidth requirements for a variety of applications and the associated
wireless technology that can support such requirements . 14
Figure 5 – Structured fabric design of layered wireless for an industrial facility . 15
Figure 6 – Inexpensive wireless sensors in a fossil-fuel plant . 16
Figure 7 – Functional hierarchy . 18
Figure 8 – Simplified diagram of a generic wireless sensor design . 19
Figure 9 – Standard compliant network . 20
Figure 10 – 802.15.1 (Bluetooth) frequency channels in the 2 450 MHz range . 23
Figure 11 – 802.15.4 frequency channels in the 2 450 MHz range . 24
Figure 12 – Overlapping channel assignments for 802.11 operation in the 2 400 MHz
range . 24
Figure 13 – 802.11n dual stream occupies 44 MHz of bandwidth. Dual stream 802.11n
in the 2,4 GHz band . 25
Figure 14 – VSAT mini-hub network configuration . 26
Figure 15 – Spatial resolution is provided in multiple axes only if the tag (target in this
Figure) is in communications with multiple APs . 28
Figure 16 – ISO 24730-2 architecture . 29
Figure 17 – Wireless vibration system at ANO . 32
Figure 18 – ANO wireless tank level system . 33

– 4 – IEC 62918:2014  IEC 2014
Figure 19 – Installation of accelerometers on ORNL HFIR cold source expansion
engines (9-2010) . 35
Figure 20 – Cold source expansion engine monitoring system software . 35
Figure 21 – Installation of permanent wireless monitoring system at ORNL HFIR
cooling tower (8-2011) . 36
Figure 22 – System commissioned in August 2011 . 36
Figure 23 – Identification of containment in a nuclear facility . 38
Figure 24 – Non-overlapping 802.11b/g channels and 802.15.4 channels . 39
Figure 25 – Spectral analysis of Wi-Fi traffic for the case where a) minimal wi-fi
channel “usage” and b) streaming video transfer across Wi-Fi channel 7 are analyzed . 39
Figure 26 – Multipath is exemplified in this indoor environment as the signal from
Source (S) to Origin (O) may take many paths . 41
Figure B.1 – The Open Systems Interconnection (OSI) model defines the end-to-end
communications means and needs for a wireless field transmitter to securely
communicate with a distributed control system (DCS) . 57
Figure B.2 – Operating frequencies for an IEEE 802.15.4 radio are 868 MHz, 902-
926 MHz and 2 405-2 485 MHz. The worldwide license-free band at 2400 MHz is
shown . 58
Figure B.3 – Networking topologies take many forms with associated levels of
complexity required for robust fault-tolerant data transport . 58
Figure B.4 – Typical mesh network diagram . 59
Figure B.5 – Requirement for mesh-networking communication of Figure B.4’s topology . 60
Figure B.6 – RF footprint map for a mesh network gateway and four nodes . 61
Figure B.7 – The connectivity diagram for Figure B.6’s RF footprint coverage map . 61
Figure B.8 – Representation of the latency and indeterminism that it takes for a
message to be transported through a mesh network that relies on time synchronization . 63
Figure B.9 – The technical specifications associated with ISA100.11a end at the
gateway. The area shaded falls within the Backhaul Work Group, ISA100.15 . 64
Figure B.10 – ISA100.11a utilizes the best topology for the application, in this case, a
star 64
Figure B.11 – ISA100.11a allows for the deployment of multiple “hub and spoke”
network elements with high speed interconnection to a gateway . 65
Figure B.12 – The ISA100.11a network deployed at Arkema was a logical mix of
wireless field transmitters and an ISA100.15 backhaul network . 65
Figure B.13 – Networks deployed at neighbouring facilities will not “cross-talk” if non-
routing nodes are deployed along the periphery of each facility . 66
Figure B.14 – State transition diagram showing various paths to joining a secured
network . 68

Table 1 – List of “industrial” radio technology standards and their candidate
applications . 21
Table 2 – Cellular telephony frequencies in the US . 22
Table 3 – GSM frequency bands, channel numbers assigned by the ITU . 23
Table 4 – Specific uses of wireless technologies in the nuclear industry . 30
Table A.1 – Use of 5 GHz in America, Asia/Pacific, and Europe . 50

IEC 62918:2014  IEC 2014 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
NUCLEAR POWER PLANTS –
INSTRUMENTATION AND CONTROL IMPORTANT TO SAFETY –
USE AND SELECTION OF WIRELESS DEVICES TO BE
INTEGRATED IN SYSTEMS IMPORTANT TO SAFETY

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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The main task of IEC technical committees is to prepare International Standards. However, a
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data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 62918, which is a technical report, has been prepared by subcommittee 45A:
Instrumentation, control and electrical systems of nuclear facilities, of IEC technical
committee 45: Nuclear instrumentation.

– 6 – IEC 62918:2014  IEC 2014
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
45A/947/DTR 45A/963/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

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IEC 62918:2014  IEC 2014 – 7 –
INTRODUCTION
a) Technical background, main issues and organisation of the Standard
The ad hoc meeting of the IEC Technical Working Group on Nuclear Power Plant Control
and Instrumentation, held in Yokohama in May 2009, resulted in the recommendation to
develop a technical report addressing the applicability of incorporating wireless technology
throughout nuclear power plant systems, regardless of the categorizations such as non-
safety, important to availability and important to safety.
This technical report addresses this recommendation and one of its main objectives is to
pave the way for the development of a standard on the topic. The technical report
addresses concerns regarding the application, safety and security of integrating wireless
technologies into the systems of nuclear power plants. It reviews the motivation for use of
wireless applications in nuclear power plants, wireless technology considerations, and the
feasibility of incorporating wireless technology in nuclear power plants.
It is intended that this Technical Report be used by operators of NPPs (utilities), systems
evaluators and by licensors.
b) Situation of the current Technical Report in the structure of the IEC SC 45A standard
series
IEC 62918 as a technical report is a fourth level IEC SC 45A document.
For more details on the structure of the IEC SC 45A standard series, see item d) of this
introduction.
c) Recommendations and limitations regarding the application of this Technical Report
It is important to note that a technical report is entirely informative in nature. It gathers
data collected from different origins and it establishes no requirements.
d) Description of the structure of the IEC SC 45A standard series and relationships
with other IEC documents and other bodies’ documents (IAEA, ISO)
The top-level document of the IEC SC 45A standard series is IEC 61513. It provides
general requirements for I&C systems and equipment that are used to perform functions
important to safety in NPPs. IEC 61513 structures the IEC SC 45A standard series.
IEC 61513 refers directly to other IEC SC 45A standards for general topics related to
categorization of functions and classification of systems, qualification, separation of
systems, defence against common cause failure, software aspects of computer-based
systems, hardware aspects of computer-based systems, and control room design. The
standards referenced directly at this second level should be considered together with
IEC 61513 as a consistent document set.
At a third level, IEC SC 45A standards not directly referenced by IEC 61513 are standards
related to specific equipment, technical methods, or specific activities. Usually these
documents, which make reference to second-level documents for general topics, can be
used on their own.
A fourth level extending the IEC SC 45A standard series, corresponds to the Technical
Reports which are not normative.
IEC 61513 has adopted a presentation format similar to the basic safety publication
IEC 61508 with an overall safety life-cycle framework and a system life-cycle framework.
Regarding nuclear safety, it provides the interpretation of the general requirements of
IEC 61508-1, IEC 61508-2 and IEC 61508-4, for the nuclear application sector, regarding
nuclear safety. In this framework IEC 60880 and IEC 62138 correspond to IEC 61508-3 for
the nuclear application sector. IEC 61513 refers to ISO as well as to IAEA GS-R-3 and
IAEA GS-G-3.1 and IAEA GS-G-3.5 for topics related to quality assurance (QA).
The IEC SC 45A standards series consistently implements and details the principles and
basic safety aspects provided in the IAEA code on the safety of NPPs and in the IAEA
safety series, in particular the Requirements SSR-2/1, establishing safety requirements
related to the design of Nuclear Power Plants, and the Safety Guide NS-G-1.3 dealing with
instrumentation and control systems important to safety in Nuclear Power Plants. The

– 8 – IEC 62918:2014  IEC 2014
terminology and definitions used by SC 45A standards are consistent with those used by
the IAEA.
NOTE It is assumed that for the design of I&C systems in NPPs that implement conventional safety functions (e.g.
to address worker safety, asset protection, chemical hazards, process energy hazards) international or national
standards would be applied, that are based on the requirements of a standard such as IEC 61508.

IEC 62918:2014  IEC 2014 – 9 –
NUCLEAR POWER PLANTS –
INSTRUMENTATION AND CONTROL IMPORTANT TO SAFETY –
USE AND SELECTION OF WIRELESS DEVICES TO BE
INTEGRATED IN SYSTEMS IMPORTANT TO SAFETY

1 Scope
This Technical Report describes the state of wireless technology for industrial applications in
fossil and chemical plants and discusses the specific issues to be addressed in order to apply
wireless technologies to nuclear power plants.
The review of the technology behind wireless communication and the status of existing
implementations are described in Clauses 7 and 8, respectively. Issues associated with
wireless implementations in nuclear facilities are discussed in Clause 10, and final
conclusions are presented in Clause 11 of this Technical Report.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61508 (all parts), Functional safety of electrical/electronic/programmable electronic
safety-related systems
IEC 61513, Nuclear power plants – Instrumentation and control for systems important to
safety – General requirements for systems
IEC 62591, Industrial communication networks – Wireless communication network and
communication profiles – WirelessHART™
IEC PAS 62734, Industrial communication networks – Fieldbus specifications – Wireless
systems for industrial automation: process control and related applications (Based on ISA
100.11a)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
access control
protection of system resources against unauthorized access; a process by which use of
system resources is regulated according to a security policy and is permitted by only
authorized entities (users, programs, processes, or other systems) according to that policy
3.2
authenticate
verify the identity of a user, user device, or other entity, or the integrity of data stored,
transmitted, or otherwise exposed to unauthorized modification in an information system, or to
establish the validity of a transmission

– 10 – IEC 62918:2014  IEC 2014
3.3
communications protocol
set of standard rules for data representation, signaling, authentication and error detection
required to send information over a communications channel
3.4
cybersecurity
actions required to preclude unauthorized use of, denial of service to, modifications to,
disclosure of, loss of revenue from, or destruction of critical systems or informational assets
3.5
Defense in Depth
DiD
application of more than one protective measure for a given safety objective, such that the
objective is achieved even if one of the protective measures fails
[SOURCE: IAEA Safety Glossary, edition 2007]
3.6
denial of service
prevention or interruption of authorized access to a system resource or the delaying of system
operations and functions
3.7
Distributed Control System
DCS
type of control system in which the system elements are dispersed but operated in a coupled
manner. A DCS is similar to a supervisory control and data acquisition (SCADA) system
except that a DCS is usually located within a more confined area (such as a factory). It uses a
high-speed communications medium, which is usually a separate wire (network) from the
factory’s primary local area network (LAN). A significant amount of closed-loop control can
reside in the DCS.
3.8
Electromagnetic Compatibility
EMC
capacity of electrical equipment or system to function satisfactorily in its electromagnetic (EM)
surroundings without radiating EM disturbance variables that are unacceptable for other
equipment in these surroundings. Requirements are balanced with regard to interface
transmission and immunity in case of EMC.
3.9
encryption
cryptographic transformation of data (called plaintext) into a form (called ciphertext) that
conceals the data’s original meaning to prevent it from being identified or used by outsiders.
Decryption is the corresponding reversal process
3.10
Industrial, Scientific and Medical band
ISM band
section of radio spectrum allocated by the International Telecommunication Union (ITU) and
many national regulators to ISM use. Radio communication systems that use these frequency
bands are typically free for use but typically operate under a “license- exempt” regime that
sets limits on power, spectrum spreading techniques, or duty cycles. Any device that
transmits in the ISM bands must be “type-approved.”
3.11
interoperability
ability of diverse systems and organizations to work together (inter-operate)

IEC 62918:2014  IEC 2014 – 11 –
3.12
Intrusion Detection System
IDS
type of security management service for computers and networks. An intrusion detection
system (IDS) monitors, gathers, and analyses information from various areas within a device
or a network to identify possible security breaches, including intrusions and misuse.
3.13
risk assessment
process of systematically identifying potential vulnerabilities to valuable system resources and
threats to those resources; quantifying loss exposures and consequences based on
probability of occurrence; and [optionally] recommending how to allocate resources to
countermeasures to minimize total exposure
3.14
trustworthiness
likelihood that an entity will behave as expected. In the context of industrial automation,
attributes of trustworthiness include reliability, security, and resiliency
3.15
Virtual Private Network
VPN
VPN extends a private network and the resources contained in the network across public
networks like the Internet. It enables a host computer to send and receive data across shared
or public networks as if it were a private network, with all the functionality, security and
management policies of the private network
3.16
vulnerability
flaw or weakness in a system’s design, implementation, or operation and management that
could be exploited to violate the system’s security policy
4 Motivation
Aging nuclear power plant equipment and systems can benefit from additional instrumentation
to detect and prevent equipment faults. Installing wired sensors into existing plant can be
costly, cumbersome, and time consuming. In addition, as shown in Figure 1, the cost of
installing wired sensor is often higher than the actual sensor itself. A wireless sensor network
can eliminate cost of installing wires for the transmission of sensed data.

– 12 – IEC 62918:2014  IEC 2014

IEC
Figure 1 – Cost comparison – Wired versus wireless
for an extensive building automation system
In many instances, a sensor network may be installed in one area of a facility while the sensor
readings are to be used somewhere else at the facility (i.e., not within the RF coverage of the
sensor network). In such a situation, some form of backhaul network is to be used to get the
readings from point A to point B. Both nuclear and traditional fossil power plants have found it
financially beneficial to use the same backhaul for the transport of differing types of
information (such as security video, sensor readings (from condition monitoring
instrumentation), and voice). Such "triple play" usage may further enhance the return on
investment (ROI) associated with any or all aspects of such a wireless installation. Process
and/or Important to Safety wireless networks shall have a documented specification and only
carry data that complies with this specification. Wireless technology enhances facility
maintainability since wireless devices are easily upgraded or replaced without major
infrastructure impact as technology and or needs change. The general application of wireless
technologies in power generation facilities – and in particular nuclear power plants – is far
from static. In a 2009 article [3] , the results of a survey yielded the wireless usage
assessment, shown here as Figure 2.
IEC
Figure 2 – Wireless use in nuclear power plants
Furthermore, this article related the wide range of possible applications of wireless technology
within the nuclear power plant setting. The associated graphic is presented as Figure 3.
_______________
Number in square brackets refer to the Bibliography.

IEC 62918:2014  IEC 2014 – 13 –
In 2006, a study ascertained the state of the art in wireless technology and the implications
for nuclear power facilities. The resulting document [30], presented a broad ranging
examination of areas where wireless systems could benefit nuclear facilities. The following
text, extracted from the report, sets the stage:
As the nuclear power industry moves to upgrade many of its older electronic systems,
wireless technology may become an attractive alternative to wired systems. One of the
largest costs in upgrading systems at nuclear facilities is the cost of running cables in this
environment. When cost is considered, the perceived benefit of deploying wireless
technology becomes clear. The benefits of using wireless systems in nuclear facilities
could expand the argument for cost savings to include the possibility of ubiquitous (ever-
present) sensing. To deploy an extensive number of sensors in the current nuclear
environment would be cost-prohibitive because of cabling costs. However with wireless
technology, additional types of sensors could be deployed to provide a more in-depth
understanding of the area or process being monitored. In addition, the number of sensors
of any given type could be increased, thereby improving redundancy. Also, with wireless
technology, diversity in the types of sensors could be used to improve reliability.
A specific tenor of that report is summarized in the following statement:
There could also be safety benefits.
IEC
Figure 3 – Possible application areas for wireless
instrumentation in a nuclear power plant
In conclusion, the motivation for use of wireless technologies is strong, with several
applications already seeing use in nuclear power plants currently. It is likely that the current
pace of technology deployment will at least continue and may accelerate in the near term.
This technical report includes information important to technology adopters and current users
by showcasing the current technologies and applications available in this growing field.
5 Generic applications
The deployment and value of industrial wireless is based on two broad application classes;
those requiring mobility and those derived from the reduced cost of attachment – not having

– 14 – IEC 62918:2014  IEC 2014
to run the wire. Such applications are best served by differing wireless technologies, typically
based on response time and bandwidth requirements. An unscientific mapping of
applications-bandwidth-wireless technology is presented as Figure 4.
The diagram is meant to depict the (approximate) upper boundary of the delivered bandwidth
for the shown technologies.
The diagram illustrates that, in the case of wireless sensor networks using 802.15.4-RF
underpinnings, the bandwidth for the transmission is in the order of 256 kbps, less than
optimal for video transmission. Similarly, the sensor networks are configured with typically up
to 50 wireless field transmitters per gateway. The aggregate output bandwidth from the
gateway is beyond the limits for efficient 802.15.4 transport and is more applicable for 802.11,
802.16 or similar backhaul technologies.
At the plant this results in a structured fabric design as depicted in Figure 5. The small circles
on the fabric layers represent an RF footprint originating from, for example, a 100 mW output,
omnidirectional antenna transceiver 802.15.4 or 802.11 device. The primary purpose of the
diagram is to illustrate how a layer of wireless sensor devices are intertwined with a layer
gateway device which, in turn, may communicate with an 802.11-based dense RF footprint
which comprises the network fabric that mobility applications require.
IEC
Figure 4 – Bandwidth requirements for a variety of applications and the
associated wireless technology that can support such requirements
_______________
“Unscientific” in the sense that this is not an all-inclusive list of candidate RF technologies. Also note that, for
example, the bandwidth for 802.11 is depicted as roughly 1 Mbps to 200 Mbps. The actual bandwidth may be
as low as essentially 0 Mbps. Similar variations in the depiction of applicable bandwidths for the other
technologies exist.
IEC 62918:2014  IEC 2014 – 15 –
AP mobility fabric
Gateway fabric
Sensor fabric
Industrial facility
IEC
Figure 5 – Structured fabric design of layered
wireless for an industrial facility
Using a designed solution – versus haphazard deployment – the result is an industrial site
that may have a wide assortment of wireless technologies operating side-by-side at the plant
with minimal (if any) RF coexistence.
In existing nuclear power plants, it may be impossible, impractical, or cost-prohibitive to add
new sensors if they are to be hardwired to a monitoring location. Furthermore, the perception
is that the cost and difficulty in hardwiring new sensors in a nuclear power plant is often not
worth the benefits that can be gleaned from additional condition monitoring. As such,
advanced predictive maintenance techniques have not served the industry as well as would
be possible. Wireless sensors will help resolve this issue. Additionally, wireless technology for
extending the plant network has shown promise in the US nuclear industry resulting in
improved dissemination of information and overall personnel efficiency.
Voice communications can include the use of two-way radios, Voice over Internet Protocol
(VoIP) telephony, etc. VoIP phones are becoming more prevalent in some nuclear industries
offer a great degree of flexibility for voice communications throughout the plant.
Communications include the use of laptops or PDAs for the upload of data to the plant
network, general network access, and data communications. Typically, Wi-Fi 802.11 networks
are used for this purpose with strategically placed access points in necessary locations.
There are several nuclear plants which are using wireless sensors for asset condition
monitoring. This can include wireless vibration sensors for traditional condition monitoring of
rotating equipment, facilities monitoring, and more. This is seen as one of the most beneficial
uses of wireless technology in the nuclear power industry. As an example of test relating to
the in-service inspection in nuclear power plants, it is required that many sensors are
temporarily installed for gathering the data for plant integrity checks in the case of the integral
leak rate test.
The wireless smart transmitter composed of an RF transmitter at 424 MHz, a sufficient battery
power supplies, RTD and humidity sensors and enclosures has been used in the integrated
leak rate tests at nuclear power plants, with its specific ad hoc communication network. Each
test has been successfully performed at pressurized water reactors.
In certain facilities, wireless cameras are being used for physical security purposes, analog
gauge readings, personnel monitoring and so on. This has proven to be a simple and effective

– 16 – IEC 62918:2014  IEC 2014
use of the technology. Specificall
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