IEC 62534:2010

Radiation protection instrumentation - Highly sensitive hand-held instruments for neutron detection of radioactive material

IEC 62534:2010 applies to hand-held instruments used for the detection and localization of neutron emitting radioactive material. These instruments are highly sensitive meaning that they are designed to detect slight variations in the range of usual background that may be caused by illicit trafficking or inadvertent movement of radioactive material. This high sensitivity allows scanning of larger volume items such as vehicles and containers. The object of this standard is to establish performance requirements, provide examples of acceptable test methods, and to specify general characteristics, general test conditions, radiation characteristics, electrical safety, and environmental characteristics, that are used to determine if an instrument meets the requirements of this standard.

Instrumentation pour la radioprotection - Instruments portables de haute sensibilité pour la détection neutronique de matières radioactives

La CEI 62534:2010 s'applique aux instruments portables utilisés pour la détection et la localisation des substances radioactives émettant des neutrons. Ces instruments sont à haute sensibilité, ce qui signifie qu'ils sont conçus pour détecter de faibles variations dans le domaine de l'environnement habituel, lesquelles peuvent avoir pour origine le transport illicite ou des mouvements fortuits de substances radioactives. Cette haute sensibilité permet le balayage d'objets de grand volume, tels que des véhicules et des conteneurs. L'objet de la présente Norme est d'établir des exigences d'aptitude à la fonction, de fournir des exemples de méthodes d'essai acceptables et de spécifier des caractéristiques générales, des conditions générales d'essai, des caractéristiques de rayonnement, des caractéristiques de sécurité électriques et environnementales, qui sont utilisées pour déterminer si un instrument est conforme aux exigences de la présente Norme.

General Information

• Status: Published
• Publication Date: 20-Jun-2010
• ICS: 13.280 - Radiation protection
• Technical Committee: SC 45B - Radiation protection instrumentation
• Drafting Committee: WG 15 - TC 45/SC 45B/WG 15
• Current Stage: PPUB - Publication issued
• Start Date: 21-Jun-2010
• Completion Date: 15-Jul-2010

Standards Content (Sample)

IEC 62534 ®
Edition 1.0 2010-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Radiation protection instrumentation – Highly sensitive hand-held instruments
for neutron detection of radioactive material

Instrumentation pour la radioprotection – Instruments portables de haute
sensibilité pour la détection neutronique de matières radioactives

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IEC 62534 ®
Edition 1.0 2010-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Radiation protection instrumentation – Highly sensitive hand-held instruments
for neutron detection of radioactive material

Instrumentation pour la radioprotection – Instruments portables de haute
sensibilité pour la détection neutronique de matières radioactives

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
U
CODE PRIX
ICS 13.280 ISBN 978-2-88912-004-8
– 2 – 62534 © IEC:2010
CONTENTS
FOREWORD.5
1 Scope and object.7
2 Normative references .7
3 Terms and definitions .8
3.1 General .8
3.2 Definitions .8
3.3 Quantities and units .9
4 General requirements .9
4.1 General characteristics.9
4.2 Physical configuration .10
4.3 Basic information.10
4.3.1 Documentation supplied .10
4.3.2 Radiation detector .10
4.3.3 Size.10
4.3.4 Weight.10
4.4 Operating modes.10
4.4.1 Monitor mode .10
4.4.2 Search mode .10
4.4.3 Integration mode .10
4.5 Maintenance/Calibration.11
4.6 Communication interface .11
4.7 User interface.11
4.8 Markings .11
4.8.1 General .11
4.8.2 Exterior markings .11
4.9 Power supply.12
4.9.1 Requirements .12
4.9.2 External DC or AC power.12
4.10 Protection of switches .12
4.11 Display units .12
4.12 Effective range of measurement .12
4.13 Alarms.13
4.13.1 Source indication alarm .13
4.13.2 Personal protection alarm.13
4.14 Explosive atmospheres .13
4.15 Indication features.13
5 General test procedure.13
5.1 Nature of test .13
5.2 Reference conditions and standard test conditions .13
5.3 Statistical fluctuations .13
6 Radiation tests .14
6.1 Rate of false source indication alarm.14
6.1.1 Requirements .14
6.1.2 Test method .14
6.2 Alarm and response time.14
6.2.1 Requirements .14

62534 © IEC:2010 – 3 –
6.2.2 Test method .14
6.3 Neutron alarm in the presence of photons .15
6.3.1 Requirements .15
6.3.2 Test method .15
6.4 Over-range characteristics for neutron alarm.15
6.4.1 Requirements .15
6.4.2 Test method .15
6.5 Personal protection alarm.15
6.5.1 Requirements .15
6.5.2 Test method .15
6.6 Warm-up time.16
6.6.1 Requirements .16
6.6.2 Test method .16
7 Environmental, mechanical and electrical performance requirements .16
7.1 Temperature.16
7.1.1 Requirements .16
7.1.2 Test method .16
7.2 Humidity.17
7.2.1 Requirements .17
7.2.2 Test method .17
7.3 Cold temperature start-up.17
7.3.1 Requirements .17
7.3.2 Test method .17
7.4 Dust and moisture resistance .17
7.4.1 Requirements .17
7.4.2 Test method – Dust .18
7.4.3 Test method – Moisture .18
7.5 Mechanical.18
7.5.1 Drop .19
7.5.2 Vibration.19
7.6 Impact (Microphonics) .19
7.6.1 Requirements .19
7.6.2 Test method .19
7.7 Battery requirements .20
7.7.1 Requirements .20
7.7.2 Test method .20
7.8 Electrostatic discharge .20
7.8.1 Requirements .20
7.8.2 Test method .20
7.9 Radio Frequency (RF) .21
7.9.1 Requirements .21
7.9.2 Test method .21
7.10 Radiated emissions .21
7.10.1 Requirement.21
7.10.2 Test method .21
7.11 Conducted immunity.21
7.11.1 Requirements .21
7.11.2 Test method .21
7.12 Magnetic fields .22

– 4 – 62534 © IEC:2010
7.12.1 Requirements .22
7.12.2 Test method .22
8 Documentation .22
8.1 General .22
8.2 Type test report.22
8.3 Certificate .22
8.4 Operation and maintenance manual .23
Bibliography.25

Table 1 – Reference conditions and standard test conditions .24
Table 2 – Radiated RF emission limits .24

62534 © IEC:2010 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RADIATION PROTECTION INSTRUMENTATION –
HIGHLY SENSITIVE HAND-HELD INSTRUMENTS FOR
NEUTRON DETECTION OF RADIOACTIVE MATERIAL

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
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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 62534 has been prepared by subcommittee 45B: Radiation
protection instrumentation, of IEC technical committee 45: Nuclear instrumentation.
The text of this standard is based on the following documents:
FDIS Report on voting
45B/639/FDIS 45B/653/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.

– 6 – 62534 © IEC:2010
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.
62534 © IEC:2010 – 7 –
RADIATION PROTECTION INSTRUMENTATION –
HIGHLY SENSITIVE HAND-HELD INSTRUMENTS FOR
NEUTRON DETECTION OF RADIOACTIVE MATERIAL

1 Scope and object
This International Standard applies to hand-held instruments used for the detection and
localization of neutron emitting radioactive material. These instruments are highly sensitive
meaning that they are designed to detect slight variations in the range of usual background
that may be caused by illicit trafficking or inadvertent movement of radioactive material. This
high sensitivity allows scanning of larger volume items such as vehicles and containers.
These instruments may also be used in fixed or temporally fixed unattended mode to monitor
check points or critical areas. Instruments addressed by this standard will also provide a
means to detect photon radiation for personal protection.
This standard does not apply to the performance of radiation protection instrumentation which
is covered in IEC 61005 and in IEC 61526.
The object of this standard is to establish performance requirements, provide examples of
acceptable test methods, and to specify general characteristics, general test conditions,
radiation characteristics, electrical safety, and environmental characteristics, that are used to
determine if an instrument meets the requirements of this standard.
The results of tests performed provide information to government agencies and other users on
the capability of radiation detection instruments for reliably detecting neutron sources.
Obtaining operating performance that meets or exceeds the specifications as stated in this
standard depends upon properly establishing appropriate operating parameters, maintaining
calibration, implementing a suitable response testing and maintenance program, auditing
compliance with quality requirements, and providing proper training for operating personnel.
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.
IEC 60050-393:2003, International Electrotechnical Vocabulary (IEV) – Part 393: Nuclear
instrumentation – Physical phenomena and basic concepts
IEC 60050-394:2007, International Electrotechnical Vocabulary – Part 394: Nuclear
instrumentation – Instruments, systems, equipment, and detectors
IEC 60529:2001, Degrees of protection provided by enclosures (IP Code)
IEC 61000-4-2:2008, Electromagnetic compatibility (EMC) – Part 4-2: Testing and
measurement techniques – Electrostatic discharge immunity test
IEC 61005:2003, Radiation protection instrumentation – Neutron ambient dose equivalent
(rate) meters
– 8 – 62534 © IEC:2010
IEC 61526:2005, Radiation protection instrumentation – Measurement of personal dose
equivalents Hp(10) and Hp(0,07) for X, gamma, neutron and beta radiations – Direct reading
personal dose equivalent meters and monitors
ISO 8529-1:2001, Reference neutron radiations – Part 1: Characteristics and methods of
production
3 Terms and definitions
3.1 General
For the purposes of this document, the following terms and definitions apply.
NOTE Radiation quantities and dosimetric terms are from IEC 60050-393 and IEC 60050-394.
3.2 Definitions
3.2.1
acceptance test
contractual test to prove to the customer that the instrument fulfils certain specifications
[IEV 151-16-23, modified]
[IEV 394-40-05, modified]
3.2.2
alarm
audible, visual, or other signal activated when the instrument reading exceeds a preset value
or falls outside of a preset range
[IEV 393-18-03, modified]
3.2.3
background level
radiation field in which the instrument is intended to operate which includes background
produced by naturally occurring radioactive material
3.2.4
conventionally true value
value attributed to a particular quantity and accepted, sometimes by convention, as having an
uncertainty appropriate for a given purpose
NOTE Conventionally true value of a quantity is sometimes called assigned value, best estimate of the value,
conventional value or reference value.
[IEV 394-40-10]
3.2.5
false alarm
alarm not caused by an increase in radiation level over background conditions
3.2.6
functionality test
test performed to verify that alarms activate and that radiation detection is acceptable
3.2.7
influence quantity
quantity that may have a bearing on the result of a measurement without being the subject of
the measurement
62534 © IEC:2010 – 9 –
3.2.8
manufacturer
includes the designer of the equipment
3.2.9
point of measurement
place at which the conventionally true values are determined and at which the reference point
of the instrument is placed for calibration or test purposes
3.2.10
purchaser
includes the user of the equipment
3.2.11
radioactive material
in this standard, radioactive material includes special nuclear material, unless otherwise
specifically noted
3.2.12
reference point of an instrument
mark on the equipment at which the instrument is positioned for the purpose of calibration and
testing
NOTE The point from which the distance to the source is measured.
[IEV 394-40-15, modified]
3.2.13
type test
conformity test made on one or more items representative of the production
[IEV 151-16-16]
[IEV 394-40-02]
3.3 Quantities and units
In the present standard, units of the International System (SI) are used . The definitions of
radiation quantities are given in IEC 60050-393, IEC 60050-394.
The following units may also be used:
–19
– for energy: electron-volt (symbol: eV), 1 eV = 1,602 × 10 J;
– for time: years (y), days (d), hours (h), minutes (min).
Multiples and submultiples of SI units will be used, when practicable, according to the SI
system.
4 General requirements
4.1 General characteristics
Instruments addressed by this standard are used for the detection of neutron emitting
radioactive material. These instruments are hand-held and battery-powered. They have a
significantly higher detection capability than pocket-sized devices which allows them to be
used to search around larger volume items such as vehicles and containers.
—————————
The International System of Units, 8th edition, 2006.

– 10 – 62534 © IEC:2010
4.2 Physical configuration
The instrument case design shall meet the requirements stated for IP code 53 (see
IEC 60529).
Controls and adjustments that may affect the operation of the instrument including setting of
alarms shall be designed so that access to them is limited to authorized persons.
Provisions shall be made to permit testing of visual and/or sound warning indicators without
the use of radiation sources.
Alarm threshold values shall be calculated by the instrument automatically using background
measurements and user definable alarm factors.
4.3 Basic information
4.3.1 Documentation supplied
The manufacturer shall provide instrument performance specifications and instructions for
operation. See Clause 8 for details.
4.3.2 Radiation detector
Manufacturer provided information shall describe the radiation detector types used for neutron
detection and the personal protection alarm (e.g., He, GM). For gas-filled counter tubes the
internal pressure shall be stated by the manufacturer.
The instrument’s fluence response to bare and moderated Cf shall be stated by the
manufacturer.
4.3.3 Size
The dimensions of the instrument shall be specified by the manufacturer with maximum
dimensions of 350 mm × 200 mm × 150 mm excluding the handle.
4.3.4 Weight
The weight or mass of the instrument shall be specified by the manufacturer and should be
less than 5 kg.
4.4 Operating modes
4.4.1 Monitor mode
The instrument shall have the ability to monitor the area surrounding the instrument for
changes in radiation levels that may be caused by a source passing through the area. This
shall be done without actions by the user and shall work autonomously. The user shall have
the ability to select whether the alarm will be silent or audible, and visual or not.
4.4.2 Search mode
The instrument shall have a search function that is activated by the user. The instrument shall
provide an audible and visual indication when operated in search mode. Audible and visual
indications shall be related to the magnitude of the radiation field (e.g., increasing frequency
or pitch of beep tone with increasing radiation signal) for eyes-free searching and localization.
4.4.3 Integration mode
The instrument shall have the ability to integrate counts for an extended period of time. The
start and end of the integration time shall be user activated with the accumulated counts

62534 © IEC:2010 – 11 –
displayed as the measurement proceeds. An alarm shall be provided based on the
accumulated counts. The integrated mode alarm method shall be described by the
manufacturer.
4.5 Maintenance/Calibration
The instrument shall have an access-controlled, menu-driven mode that will allow personnel
to check and perform adjustments as needed to calibrate the instrument as well as make
adjustments to factors that can control the response of the instrument.
4.6 Communication interface
The instrument shall have the ability to transfer data to another device such as a personal
computer. The manufacturer shall provide a full description of the transfer data format. “XML”
format based on ANSI N42.42 is recommended.
4.7 User interface
The following are considered essential or desirable:
a) the following shall be provided:
– simple to use for non-expert users and user-friendly controls for routine operation,
– neutron radiation alarms with visual and audible alarms,
– display that provides a method to track radiation levels when operating in the “search”
mode,
– display that provides a real-time radiation level indication that can be viewed when
operating in the “monitor” mode,
– audible and/or visual indication that is related to the magnitude of the radiation field
(e.g., increasing frequency or pitch of beep tone with increasing radiation signal) for
eyes-free searching and localization,
– readable display in all lighting conditions including darkness,
– protection of the setting of all operational parameters, if available,
– controls and switches that are designed in a way to minimize accidental operation,
– diagnostic capabilities,
– indication of battery status, and
– the capability to operate if the user is wearing gloves.
b) the following should be provided:
– silent alarms for covert operation such as vibration alarm and/or earphone connection
with an adjustable volume to cope with the large variations in human hearing
sensitivity and noise level.
4.8 Markings
4.8.1 General
All external instrument controls, displays, and adjustments shall be identified as to function.
Internal controls needed for operation shall be identified through markings and identification in
technical manuals. External markings shall be easily readable and permanently fixed under
normal conditions of use.
4.8.2 Exterior markings
The following markings shall appear on the exterior of the instrument or each major assembly
(e.g., detector probe) as appropriate:
• manufacturer and model number,

– 12 – 62534 © IEC:2010
• unique serial number,
• location of the reference point, and
• function designation for controls, switches, and adjustments that are not menu or software
driven.
Markings shall be easily readable and permanently fixed under normal conditions of use
(including use of normal decontamination procedures).
4.9 Power supply
4.9.1 Requirements
Instruments shall be equipped with a test circuit or other visible direct indicator of battery
condition for each battery circuit.
The manufacturer shall state the expected continuous operating time using the recommended
batteries and the conditions (functional and environmental) used to determine this time.
The instrument shall be fully operational for a minimum of 8 h after warm-up under standard
test conditions. The low-battery indication shall be no lower than the minimum voltage
required for proper operation.
If operated using consumable batteries, the batteries shall be widely available, not unique to
the instrument, and be field replaceable (e.g., AA) with no special tools. Battery chargers shall
meet appropriate electrical standards.
4.9.2 External DC or AC power
The instrument should be capable of operating from an external DC or AC source. Adequate
protection from reverse polarity, over-voltage, and electrical noise shall be provided. AC or
DC power sources may include:
a) 12 V DC as would be obtained from a 12-volt vehicle electrical system.
b) A portable battery pack, such as one that can be worn, that supplies 4 V DC to 28 V DC.
c) A regulated 12 V DC power supply operating from mains power.
d) A single phase 100 V AC to 240 V AC 50 Hz – 60 Hz power supply.
Requirements are verified by observation of the instrument and review of manufacturer-
provided information.
4.10 Protection of switches
Switches and other controls should be protected to minimize or prevent inadvertent
deactivation or improper operation of the instrument.
4.11 Display units
Neutron indication shall be in counts per second.
4.12 Effective range of measurement
The neutron energy range shall be from thermal to fast neutrons with tests performed using
moderated and unmoderated Cf.
The manufacturer shall also state the range for neutron count rate indication.

62534 © IEC:2010 – 13 –
4.13 Alarms
4.13.1 Source indication alarm
A source indication alarm shall be provided when the measured neutron field (count rate) is
above the source indication alarm threshold. This alarm threshold shall be calculated by the
instrument from the background measurement by adding a user-defined count rate increment
or number of standard deviations (depending on instrument operating mode). The alarm shall
be both audible and visual, and not be affected by slowly increasing radiation fields that could
cause a slow change in the alarm threshold. It shall not be possible to switch off all alarm
indications at the same time.
4.13.2 Personal protection alarm
Alarms shall be provided to alert the user when the measured neutron field (counts per
second) or the photon radiation field intensity are above a user-selected threshold level
–1
(typically 100 μSv.h ). Each alarm shall be audible and visual, be different from the neutron
source indication alarm, and adjustable through the restricted mode. For the personal
protection photon radiation alarm, the alarm value shall be based on Cs. For neutron, the
alarm value shall be based on the spectrum from Cf.
The personal protection alarm shall be functional over the stated range of the instrument.
4.14 Explosive atmospheres
The manufacturer shall state as to whether the instrument is certified for use in explosive
atmospheres and its category. Proof of certification shall be provided when claimed.
4.15 Indication features
The instrument shall provide an indication of its operational status and alarm condition. The
user shall have the ability to select the visibility of the status indication.
All alarm indicators shall automatically or manually reset as defined by the user.
5 General test procedure
5.1 Nature of test
Unless otherwise specified in the individual steps, all tests enumerated in this standard are to
be considered type tests. Certain tests may be considered acceptance tests by agreement
between the purchaser and the manufacturer.
When performing radiation tests as described in this standard, the reference point of the
instrument shall be placed at the point of measurement and the instrument shall be oriented
with respect to the direction of the radiation source as indicated by the manufacturer.
5.2 Reference conditions and standard test conditions
Reference conditions are given in Table 1. Except where otherwise specified, tests shall be
carried out under the standard test conditions in accordance with Table 1. For those tests
carried out under standard test conditions, the values of temperature, pressure, and relative
humidity shall be stated and the appropriate corrections made to give the response under
reference conditions. The values of any corrections should be stated.
5.3 Statistical fluctuations
For any test involving the use of radiation, if the magnitude of the statistical fluctuations of the
indication arising from the random nature of radiation alone is a significant fraction of the

– 14 – 62534 © IEC:2010
variation of the indication permitted in the test, then sufficient readings shall be taken to
ensure that the mean value of such readings may be estimated with sufficient precision to
determine whether the requirements for the characteristic under test are met.
The interval between such readings shall be sufficient to ensure that the readings are
statistically independent.
6 Radiation tests
6.1 Rate of false source indication alarm
6.1.1 Requirements
The false alarm rate for the source indication alarm shall be less than or equal to 1 per 1 h of
continuous use when operated in a stable background environment.
6.1.2 Test method
The alarm threshold shall be the same as used in 6.2 and 6.3.
Place the instrument in an area with a stable and controlled background radiation level and
switch on the instrument. Observe the instrument for a period of 8 h and note the number of
alarms during that time interval. The average false alarm rate during this period shall not
exceed 1 alarm in 1 h.
6.2 Alarm and response time
6.2.1 Requirements
The instrument shall indicate the presence of neutron radiation when exposed separately to
both an unmoderated and moderated neutron field within a period of not more than 2 s of the
exposure.
6.2.2 Test method
Neutron tests should be made in a low scatter irradiation facility (see ISO 8529-1:2001) or
with the instrument placed in an area where there is open space on all sides of at least 1 m
around the instrument and source. The alarm set point shall be set to the same value as that
used for the false alarm test.
Expose the instrument to a neutron fluence of 0,1 n/s.cm (± 20 %) from a Cf source.
Photons from the source shall be shielded with 1 cm of lead. The source to instrument
distance shall be between 1 m and 2 m based on direct flux.
NOTE This fluence is approximately equivalent to an unmoderated Cf source emitting 20 000 n/s placed
125 cm from the instrument. The distance chosen represents a point source placed in the center of a cargo
container (short dimension of approximately 2,48 m). This is also based on comparison with a neutron alarm
caused on a typical portal monitor.
For the test, the neutron field shall be increased to the required level within a period of not
more than 2 s. The instrument shall indicate the presence of neutrons within a period of 2 s
after the field increase. Reduce the field and repeat the test 60 additional times. The test
result is acceptable if presence is indicated in at least 59 of 61 exposures.
The test shall be repeated with a moderated neutron field obtained by placing the Cf source
at the centre of a 30 cm diameter D O moderation sphere, or equivalent moderator. The use
of an equivalent moderator shall be recorded.

62534 © IEC:2010 – 15 –
6.3 Neutron alarm in the presence of photons
6.3.1 Requirements
The instrument should not trigger a neutron alarm when exposed to a gamma ambient dose
–1
equivalent rate of up to 0,1 mSv.h .
The instrument shall indicate the presence of neutron radiation when exposed to a neutron
source while being exposed to the increased level of photon radiation.
6.3.2 Test method
The instrument shall be exposed to photons from Co at an ambient dose equivalent rate of
–1
0,1 mSv.h . Verify that that no additional neutron alarms relative to the false alarm rate are
triggered within a continuous exposure time of 5 min. In order to eliminate dependence on the
neutron detector geometry the distance between the Co source and the detector should be
at least 50 cm.
While the instrument is exposed to the elevated gamma field as stated above, expose the
instrument to the neutron source as specified in 6.2. The instrument shall trigger a neutron
alarm in 10 of 10 trials.
6.4 Over-range characteristics for neutron alarm
6.4.1 Requirements
The instrument shall indicate that an over range condition exists when the neutron radiation
level is greater than the manufacturer’s stated maximum.
6.4.2 Test method
Expose the instrument to a step change from ambient radiation background to at least
10 times that of the manufacturer-stated maximum. The instrument shall indicate that an over
range condition exists within 3 s of the step change and shall remain in that condition for the
entire exposure period (minimum of 5 min). After a minimum of 5 min exposure, reduce the
radiation field to the pre-test value. The instrument shall operate normally within 5 min.
6.5 Personal protection alarm
6.5.1 Requirements
The requirements stated in 4.13.2 shall be met.
6.5.2 Test method
Expose the instrument to a step change from the ambient radiation background to an ambient
radiation level that is 30 % greater than the personal protection alarm threshold. The
instrument shall provide an alert indicating that the measured radiation level is greater than
the pe
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