IEC 60860:2014

IEC 60860 ®
Edition 2.0 2014-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Radiation protection instrumentation – Warning equipment for criticality
accidents
Instrumentation pour la radioprotection – Equipement de signalisation des
accidents de criticité
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IEC 60860 ®
Edition 2.0 2014-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Radiation protection instrumentation – Warning equipment for criticality

accidents
Instrumentation pour la radioprotection – Equipement de signalisation des

accidents de criticité
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX Q
ICS 13.280 ISBN 978-2-8322-1638-5

– 2 – IEC 60860:2014 © IEC 2014
CONTENTS
FOREWORD . 4
1 Scope and object . 6
2 Normative references . 6
3 Terms and definitions, quantities and units . 7
3.1 Terms and definitions . 7
3.2 Quantities and units . 8
4 General requirements . 8
4.1 General characteristics . 8
4.2 Detection criterion . 8
4.3 Safety classification . 8
4.4 False alarms . 9
4.5 Failure of components . 9
4.6 Ease of decontamination . 9
4.7 Multiple function systems . 9
4.8 Interconnection cables and connectors . 9
4.8.1 Interconnecting cables . 9
4.8.2 Connectors . 10
4.9 Reliability . 10
4.10 Functional testing . 10
4.11 Interchangeability . 10
4.12 Detection subassembly . 10
4.13 Logic unit for signal treatment . 10
4.14 Alarm signals unit . 10
4.14.1 Alarm signals . 10
4.14.2 Alarm set point . 11
5 General test procedure . 11
5.1 Nature of tests . 11
5.2 Reference conditions and standard test conditions . 11
5.3 Point of test . 11
5.4 Reference radiation . 12
6 Radiation detection requirements . 12
6.1 General . 12
6.2 Energy response . 12
6.2.1 General . 12
6.2.2 Gamma detectors . 12
6.2.3 Neutron detectors . 13
6.3 Response time . 13
6.3.1 Requirements . 13
6.3.2 Method of test. 13
6.4 Alarm threshold of detection . 13
6.4.1 Requirements . 13
6.4.2 Method of test. 14
6.5 Variation of response with angle of incidence. 14
6.5.1 Requirements . 14
6.5.2 Method of test. 14

6.6 Overload characteristics . 14
6.6.1 Requirements . 14
6.6.2 Method of test. 14
7 Environmental requirements . 14
7.1 Temperature tests without source or injected electrical signal . 14
7.1.1 Requirements . 14
7.1.2 Method of test. 14
7.2 Environmental test with source or injected electrical signal . 15
7.2.1 Requirements . 15
7.2.2 Method of test. 15
8 Mechanical requirements . 15
9 Electromagnetic requirements . 15
10 Documentation . 15
Bibliography . 17

Table 1 – Reference and standard test conditions . 11
Table 2 – Summary of performance requirements . 16

– 4 – IEC 60860:2014 © IEC 2014
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RADIATION PROTECTION INSTRUMENTATION –
WARNING EQUIPMENT FOR CRITICALITY ACCIDENTS

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60860 has been prepared by subcommittee 45B: Radiation
protection instrumentation, of IEC technical committee 45: Nuclear instrumentation.
This second edition cancels and replaces the first edition issued in 1987. It constitutes a
technical revision.
The main technical changes with regard to the previous edition are as follows:
– reference to IEC 61508 concerning the safety classification;
– introducing requirement for the alarm sound level (90 dBA and 115 dBA at a distance of
1 m from the alarm source);
– energy response requirement changes from (–35 %, +35 %) to (–35 %, +50 %);
–1
– time period of 1 min is specified for the overload requirement (1 kGy∙h during a period of
at least 1 min);
– updated EMC, mechanical and environmental requirements according to IEC 62706.

The text of this standard is based on the following documents:
FDIS Report on voting
45B/791/FDIS 45B/794/RVD
Full information on the voting for the approval of this standard 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.
– 6 – IEC 60860:2014 © IEC 2014
RADIATION PROTECTION INSTRUMENTATION –
WARNING EQUIPMENT FOR CRITICALITY ACCIDENTS

1 Scope and object
This International Standard applies to equipment intended to provide warning of a criticality
accident by the detection of gamma radiation, neutrons or both from such an event.
This standard is primarily intended to apply to equipment design and, therefore, does not
address the need for placement of such equipment. The need for criticality alarm systems and
the utilisation procedures are described in ISO 7753 and ISO 11320.
The primary purpose of the criticality alarm system is to detect radiation from criticality
accidents and warn personnel. Suitable alarms shall be provided so that personnel present in
the area involved and in adjacent effected areas (often the complete facility) can be warned in
the event of a criticality accident occurring. These alarms are intended to activate an
evacuation alarm to reduce the probability of serious exposure to personnel.
Such systems may also have secondary functions, such as providing a follow-up
measurement of the radiation level during the accident. The systems should only be used for
these secondary functions, provided that the secondary functions have no adverse effect on
the criticality alarms and their essential characteristics (for example, reliability) described in
this standard.
The object of this standard is to prescribe general, radiation detection, environmental,
mechanical, electromagnetic and documentation requirements and to specify acceptance
criteria for criticality accident warning equipment.
This standard is not applicable to photon or neutron dose equivalent (rate) meters or monitors
covered by IEC 60532, IEC 60846 (all parts), IEC 61017 (all parts), and IEC 61005. This
standard is not applicable either to equipment or assemblies used in control and safety
systems of nuclear reactors.
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 60050 (all parts): International Electrotechnical Vocabulary (available at
http://www.electropedia.org)
IEC 61508 (all parts), Functional safety of electrical/electronic/programmable electronic
safety-related systems
IEC 62706, Radiation protection instrumentation – Environmental, electromagnetic and
mechanical performance requirements
ISO 7753:1987, Nuclear energy – Performance and testing requirements for criticality
detection and alarm systems
International Bureau of Weights and Measures: The International System of Units, 8th edition,
3 Terms and definitions, quantities and units
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions, as well as those given
in IEC 60050-395 apply.
3.1.1
acceptance test
contractual test to prove to the customer that the device fulfils certain specifications
3.1.2
alarm
method for notification of a criticality accident
3.1.3
alarm set point
minimum radiation dose and/or dose rate that will activate the alarm
3.1.4
conventional quantity value (dose)
quantity value attributed by agreement to a quantity for a given purpose
Note 1 to entry: The term “conventional true quantity value” is sometimes used for this concept, but its use is
discouraged.
Note 2 to entry: Sometimes a conventional quantity value is an estimate of a true quantity value.
Note 3 to entry: A conventional quantity value is generally accepted as being associated with a suitably small
measurement uncertainty, which might be zero.
Note 4 to entry: In this standard the quantity is the dose.
[SOURCE: VIM:2007, 2.12]
3.1.5
criticality accident
release of energy as a result of an accidentally produced self-sustained or divergent neutron
chain reaction
3.1.6
criticality alarm system
all parts of the assembly, subassemblies, functional units and components that together make
a workable system, including all circuitry, alarms, connections, cables, detectors, and
auxiliary subassemblies. The criticality alarm system comprises at least the following
subassemblies:
– detection subassembly, including associated electronics;
– warning subassembly including the logic unit and alarm unit
3.1.7
false alarm
activation of the alarm signal in the absence of a criticality accident
3.1.8
type test
conformity test made on one or more items representative of the production

– 8 – IEC 60860:2014 © IEC 2014
3.2 Quantities and units
In the present standard, units of the International System (SI) are used . The definitions of
radiation quantities are given in IEC 60050-395. The corresponding old units (non-SI) are
indicated in brackets.
Nevertheless, the following units may also be used:
–19
– for energy: electron-volt (symbol: eV), 1 eV = 1,602 × 10 J;
– for time: hour (symbol: h) or minute (symbol: min).
4 General requirements
4.1 General characteristics
Criticality alarm systems are designed for the automatic and prompt detection of gamma
radiation or neutrons from a criticality accident and to actuate immediate evacuation and
warning alarms. The primary functions of the criticality alarm system shall be to:
– detect a criticality accident as soon as it occurs within the monitoring zone of the
detector(s);
– actuate an alarm with minimal delay;
– achieve a high degree of reliability required by its safety classification and low probability
of false alarm;
– fail safe by design and reveal failures (single failure shall be indicated but shall not disable
the system and result in a potential non-detection of a criticality accident);
– be secured against unauthorised adjustment.
Secondary functions of the criticality alarm system should be established by agreement
between the manufacturer and user. A recommended secondary function should include the
ability to measure radiation levels during and following a criticality accident.
It shall be possible to test the response and performance of the criticality alarm system
without causing personnel evacuation.
4.2 Detection criterion
The following detection criterion definition described in ISO 7753 is used. Criticality alarm
systems shall be designed to detect promptly the minimum accident of concern. For this
purpose, in typical unshielded process areas, the minimum accident may be assumed to
deliver an equivalent absorbed neutron and gamma dose in free air of 0,2 Gy at a distance of
2 m from the reacting material within 60 s. Very slowly increasing excursions, while unlikely to
occur, may not attain this value. Furthermore, excursions in unmoderated systems will
probably occur much more rapidly.
In the design of radiation detectors, it may be assumed that the minimum duration of the
radiation transient is 1 ms FWHM (Full Width Half Maximum). The criticality alarm system
shall be designed so that instrument response and latched alarm occur as a result of
transients of such duration.
4.3 Safety classification
The equipment covered in this standard may be installed in facilities such as nuclear fuel
storages and processing sites.
—————————
th
International Bureau of Weights and Measures: The International System of Units, 8 edition, 2006.

The basic safety standard IEC 61508 applies. The SIL (Safety Integrity Level) specification for
equipment shall be SIL1 as a minimum. The requirement for higher SIL specification (SIL2-4)
shall be agreed between manufacturer and purchaser. Compliance with IEC 61513 will
facilitate consistency with the requirements of IEC 61508 as they have been interpreted for
the nuclear industry.
4.4 False alarms
Particular consideration shall be given, during the design of the criticality alarm system, to
minimize false alarms.
A redundant system, requiring response from at least two detector channels out of three
(2OO3) is one of the methods used in minimising false alarms. If a redundant system is used,
alarm or failure of any single channel shall not activate the alarm or render the criticality
alarm system inoperative. A warning signal of a detected malfunction shall be provided in this
case and the system shall continue to operate as a one out of two (1OO2) redundant system
using the remaining healthy channels.
The maintenance requirements shall be kept to the minimum practicable and the equipment
shall be designed to facilitate maintenance without causing false alarms.
4.5 Failure of components
For all criticality alarm systems, it is recommended that a failure modes and effects analysis
(FMEA) in accordance with IEC 60812 is carried out to identify any potential failure modes,
their causes and the effects on system performance. This will assist in the development of the
design, and identify areas requiring modification or design improvement for mitigation against
failure modes.
Failure of components which would directly affect the detection and warning capability of the
criticality alarm system shall be designed to fail safe and reveal failures by visual and/or
audible indication.
A revealed failure shall result in corrective action being immediately taken to return the
system to full operational state. To avoid loss of confidence and disruption of work, warnings
of instrument failure should be distinguishable, whenever possible, from warnings due to
genuine radiological hazards.
4.6 Ease of decontamination
The assemblies shall be designed in such a manner as to facilitate decontamination.
4.7 Multiple function systems
If the system is to be used for secondary functions in addition to criticality accident detection,
it shall be designed in such a manner as not to compromise its primary purpose of criticality
accident detection and warning.
4.8 Interconnection cables and connectors
4.8.1 Interconnecting cables
The criticality alarm system shall include a device for self-verification to determine complete
operability with its installed interconnecting cables. These cables shall be protected from
spurious signals which could activate the warning subassembly or render the assembly
inoperative.
– 10 – IEC 60860:2014 © IEC 2014
4.8.2 Connectors
Cable connectors shall be mechanically secured.
4.9 Reliability
All assemblies shall be designed to the standard of reliability defined by the specified SIL
(Safety Integrity Level), i.e. the Probability of Failure on Demand (PFD). The manufacturer
shall specify the period between proof tests, when operational in the facility which is required
to meet the specified SIL(PFD). The manufacturer shall specify the periods between the
necessary maintenance operations, and provide full maintenance procedures. The
maintenance requirements shall be kept to the minimum practicable.
4.10 Functional testing
It is recommended that individual subassemblies and units are capable of being functionally
tested without being removed from the criticality alarm system.
4.11 Interchangeability
It is recommended that all subassemblies and units of similar function such as detectors,
readout and display units, and power supplies be of modular construction enabling easy
replacement of these items.
4.12 Detection subassembly
A detection subassembly refers to the equipment by which the radiation from a criticality
accident is detected, and may consist of more than one radiation detector and auxiliary
circuits. A detection subassembly shall:
– have suitable response to gamma radiation, neutrons or both produced by a criticality
accident (see Clause 6);
– not be inhibited by gamma and/or neutron overload dose (see overload characteristics,
6.6).
4.13 Logic unit for signal treatment
This unit processes the information originating from the detection assemblies concerning
gamma and/or neutron radiation. Failure of any one detector or any one component of the
logic unit shall not result in the failure of the criticality alarm system.
A means shall be provided to check the proper functioning of each detector channel at any
time without compromising the criticality alarm system or causing an evacuation.
4.14 Alarm signals unit
4.14.1 Alarm signals
Audible alarm signals shall be of distinctive tone, the acceptable level shall be established
between the manufacturer and user, and shall give a clear warning above background noise.
The sound level shall be between 90 dBA and 115 dBA at a distance of 1 m from the alarm
source. The audible and visual alarms shall be continuous until manually reset. Manual
activation means may also be provided, but with limited access. Manual reset should be
external to the area to be evacuated. Automatic reset after a pre-defined period could be
possible if this does not decrease the reliability of the system.
In areas with high background noise or required hearing protection, visual alarm signals or
other alarm means should be considered in addition to those stated above.

4.14.2 Alarm set point
The alarm set point of the detection system should be adjustable. The setting controls shall
be protected against unauthorized adjustment.
5 General test procedure
5.1 Nature of tests
Unless otherwise specified, all tests enumerated in this standard are to be considered type
tests. Certain tests may be considered acceptance tests by agreement between the
manufacturer and user.
5.2 Reference conditions and standard test conditions
Reference and standard test conditions are given in Table 1. Reference conditions are those
conditions to which the performance of the assembly is referred, whereas standard test
conditions indicate the necessary tolerances in practical testing. Except where otherwise
specified, the tests in this standard shall be performed under the standard test conditions
given in the third column of Table 1.
Table 1 – Reference and standard test conditions

Influence quantities Reference conditions (unless Standard test conditions (unless
otherwise indicated by otherwise indicated by
manufacturer) manufacturer)
60 252 60 252
Reference radiation sources Co and Cf Co and Cf
Warm-up time To be specified by manufacturer To be specified by manufacturer
Relative humidity 65 % 55 % to 75 %
Ambient temperature 20 °C 18 °C to 22 °C
Atmospheric pressure 101,3 kPa 86 kPa to 106 kPa
Power supply voltage Nominal power supply voltage Un Nominal power supply Un ± 5 %

Power supply frequency (AC) Nominal frequency Nominal frequency –6 % to +10 %.
Power supply waveform (AC) Sinusoidal Sinusoidal with total harmonic
distortion lower than 5 %
Angle of incidence of radiation Calibration direction given by Direction given ±10°
manufacturer
Electromagnetic field of external Negligible Less than 0,5 times the lowest value
origin that causes interference
Magnetic induction of external origin Negligible Less than twice the value of the
induction due to the earth's magnetic
field
Orientation of assembly To be stated by the manufacturer Stated orientation ±10°
Assembly control devices Set for normal operation Set for normal operation
Contamination by radioactive Negligible Negligible
elements
Background noise level Less than 60 dBA Less than 60 dBA

5.3 Point of test
The point of test is the location at which the reference position of the detection subassembly
is placed and at which the value of the appropriate quantity (for example, radiation dose
equivalent rate) is known. To calibrate the detection subassembly, it shall be placed with its
reference position at the point of test. Every effort shall be made to reduce the scatter

– 12 – IEC 60860:2014 © IEC 2014
radiation at the point of test in the absence of the detection subassembly to less than 10 % of
the desired dose rate at that point. Where this is not practicable, the appropriate correction
shall be applied.
The manufacturer shall mark on (or state for) the detection subassembly the reference
position that should correspond to the effective centre of the detector and give the direction
for calibration.
5.4 Reference radiation
60 252
Reference radiation shall be provided by Co and Cf sources, unless the manufacturer
137 60
and user agree upon the use of other sources (e.g., Cs). Co is preferred for gamma
radiation source instead of Cs since its energy is closer to the gamma energy radiated
during a criticality accident.
6 Radiation detection requirements
6.1 General
The radiation detection requirements of the detector are determined to enable the user to
install the criticality alarm system in compliance with the detection criterion in 4.2. Because of
the wide variety of radiation detectors used in criticality alarm systems, only the general
principles of testing can be given.
6.2 Energy response
6.2.1 General
The energy response of the detectors shall be such that the system will respond to any event
of concern by the detection of radiation of a specified type.
6.2.2 Gamma detectors
6.2.2.1 Requirements
The measured dose over the energy range from at least 0,1 MeV to 3 MeV shall be within an
interval (–35 %, +50 %) about the conventional dose.
6.2.2.2 Method of test
The energy response of the detector shall be determined using X or gamma reference
radiations as given in ISO 4037.
At least three reference radiations shall be used:
– one shall be at, or below, 100 keV,
– one between 100 keV and 1 MeV,
– and one above 1 MeV.
Where appropriate, additional test equipment may be used to determine the response of the
detector (for example, picoampmeter for an ionising chamber). Expose the detector
subassembly to known dose rates from the radiations used and note the indications provided
by the detector. The energy response of the detector shall comply with the above
requirements.
6.2.3 Neutron detectors
6.2.3.1 Requirements
Since widely differing types of neutron detectors (scintillators, ionisation chambers, self
powered activation detectors in moderators and junction diodes) with different energy
response characteristics may be used in criticality alarm systems, it is only possible to give
general guidelines on their use.
The response of all neutron detectors shall be determined using the reference radiation ( Cf
fission neutrons or other appropriate source). In addition for those detectors to be installed in
a moderated neutron radiation field the response of the detectors shall be determined for such
fields.
The energy response of the detector may be measured using ISO standard neutron reference
radiations (mono energetic radiations produced by an accelerator). The response of the
detector to the moderated neutron field may then be assessed using published data on the
neutron leakage spectrum for critical assemblies. Alternatively, the detector response may be
directly determined by exposure in a moderated neutron field simulated by a critical assembly
or reactor of known dose rate.
6.2.3.2 Method of test
The energy response of the detectors shall be determined using a Cf neutron radiation
source or other appropriate source (accelerator or reactor) with energy close to the energy
radiated during a criticality accident. The energy response to other reference neutron
radiations should be also determined.
The appropriate neutron energies as well as the criteria for acceptability should be specified
upon agreement between manufacturer and user. In this case, expose the detection
subassembly to known dose rates and note the indications provided by the detector. The
energy response of the detector shall comply with the criteria for acceptability.
6.3 Response time
6.3.1 Requirements
The system shall be designed to produce the criticality alarm signal within 0,3 s after the
detection of criticality event.
6.3.2 Method of test
Expose the equipment to an appropriate criticality excursion. The alarm signal shall be
produced within 0,3 s.
6.4 Alarm threshold of detection
6.4.1 Requirements
The equipment shall respond to the direct gamma radiation, neutrons, or a combination of
these radiations emitted during a criticality accident and shall meet the alarm threshold of
detection specified by the purchaser. The alarm threshold of detection shall be such that
when the equipment is installed, it will detect the equivalent of an absorbed neutron and
gamma dose in free air of 0,2 Gy at a distance of 2 m from the reacting material within 60 s
(see 4.2).
– 14 – IEC 60860:2014 © IEC 2014
6.4.2 Method of test
The alarm threshold of detection, being the minimum dose to trigger the alarm, should be
determined using an appropriate pulsed source of the test radiation. Tests should be made
with a range of radiation pulses of duration of about 1 ms to 3 s.
6.5 Variation of response with angle of incidence
6.5.1 Requirements
The angular dependent response of the detection subassembly shall be determined.
6.5.2 Method of test
With a reference radiation source having a suitable activity and positioned at a given distance,
the detection subassembly shall be rotated in steps of 30° as specified below in a) and b) and
the response to the test radiation shall be recorded. The activity and the distance shall be
specified by the manufacturer. The distance shall exceed ten times the maximum dimension
of the detection subassembly.
a) Detection subassembly rotated around a horizontal axis passing through the subassembly
and orthogonal to the axis through the subassembly and the source.
b) Detection subassembly rotated around a vertical axis passing through the subassembly.
Where appropriate, additional test equipment can be used to determine the response of the
detector. The results should be presented in the form of a polar chart.
6.6 Overload characteristics
6.6.1 Requirements
For radiation doses or dose rates greater than those required to initiate the alarm, the warning
subassembly shall be activated and remain so until reset. After the test the equipment shall
–1
function normally. Detection subassembly shall be tested to a dose rate of at least 1 kGy∙h
during a period of at least 1 min.
6.6.2 Method of test
This test shall be performed using a reactor or other appropriate source of radiation. The
detection subassembly is exposed to the above dose rate and the alarm signal shall continue
until reset. After the test the equipment shall function normally.
7 Environmental requirements
7.1 Temperature tests without source or injected electrical signal
7.1.1 Requirements
No false alarm is allowed during the temperature changes specified in IEC 62706 from –10 °C
to 40 °C.
7.1.2 Method of test
The detection equipment shall undergo the temperature tests specified in IEC 62706 for
installed instrumentation from –10 °C to 40 °C. No false shall be allowed.
These tests shall be done prior to the radiation tests.

7.2 Environmental test with source or injected electrical signal
7.2.1 Requirements
The alarm set point shall not vary by more than ± 10 % due to the environmental changes
specified in IEC 62706 from –10 °C to 40 °C.
7.2.2 Method of test
The detection equipment should undergo the environmental tests specified in IEC 62706 for
installed instrumentation from –10 °C to 40 °C. An appropriate source or an electrical injected
signal should be used in order to test that the alarm set point at the temperature extremities
shall not vary by more than ± 10 % compared to the alarm set point at 22 °C ± 2 °C.
8 Mechanical requirements
The equipment shall undergo the mechanical tests specified in IEC 62706 for installed
instrumentation. No false alarm, mechanical damage or loose components shall be allowed.
These tests will be done prior to the radiation tests.
9 Electromagnetic requirements
The equipment shall undergo the electromagnetic tests specified in IEC 62706 for installed
instrumentation. No false alarm shall be allowed.
Then, an appropriate source or an injected electric signal shall be used in order to put the
equipment in alarm conditions. The audible alarm shall be switched off and only the output
signal shall be monitored. Undergo the radio frequency immunity test as specified in
IEC 62706 for installed instrumentation and check if there is a substantial decrease of the
output signal at some frequency. The equipment shall remain in alarm condition during the
whole test.
These tests shall be done prior to the radiation tests.
10 Documentation
The manufacturers shall make available at the request of the user a report on the type tests
carried out according to the requirements of this standard.
The following documenta
...