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The scale of equipment uses may be broadly characterized by the following statistics dating to 2002:

∙550 facilities found under the safeguards were equipped with 700 nondestructive testing systems;

∙760 samples were analyzed by destructive testing;

∙400 video surveillance systems were installed at facilities;

∙24500 seals were checked;

∙230 samples were taken near 50 facilities and analyzed.

Some data on the equipment in use by the IAEA in its inspection activities are given in Tables 3.2 – 3.7.

Optical surveillance. Optical (video) surveillance equipment has an important part to play in implementation of the IAEA safeguards. It has found wide application in keeping continuity of the knowledge of nuclear materials in between inspections and has been a strong support to the means of NM accounting. By now, the Agency has installed about 800 operating video cameras (as part of 400 video systems) at 170 facilities all over the world. Table 3.2 lists some of the systems in use by the Agency at present.

The Agency adopted a program for upgrading video equipment in use. The decision was to develop surveillance systems around the electronic DCM14 unit which digitizes images, checks information for authenticity, encodes data and ensures their confidential use, compresses data, controls power of the surveillance system, etc. This unit is the best one to meet the IAEA requirements for surveillance systems. In 1998, work was initiated to create 5 base digital surveillance systems using the DCM14 unit, which would be fully consistent with the specifics of the IAEA inspection activities and immune to possible harsh environmental conditions during their operation.

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Table 3.2

Video surveillance systems in use by the IAEA in implementation of the safeguards

System

System name

Application and features

desig-

 

and type

 

nation

 

 

 

 

 

 

 

 

Single-camera surveillance systems with a tape-recording function

 

 

 

 

SIDS

Sample

 

System for identification of fuel samples at facilities for MOX

 

Identification

fuel fabrication. It has an interface with a neutron flux

 

System

 

measuring instrument (HLNC) and is actuated when the

 

 

 

 

neutron flux exceeds an established limit.

 

 

 

STVS

Short-Term

System built around the MXTV equipment and meant for short-

 

TV System

term surveillance. It comprises one camera and one recorder.

 

 

 

UWTV

Underwater

Portable system meant for underwater video surveillance. Its

 

TV

 

major application is examination of spent fuel assemblies of

 

 

 

 

CANDU reactors in a storage pool. It has appliances for

 

 

 

 

rotation of the camera and for illumination of the object of

 

 

 

 

surveillance. The camera is enclosed in a waterproof shell, it

 

 

 

 

remains operative at high radiation levels, and allows reading

 

 

 

 

small print under limited lighting conditions. The system has a

 

 

 

 

built-in monitor to scan images in situ.

 

 

 

 

 

 

 

 

Digital single-camera surveillance systems

 

 

 

 

ALIP

All

in

One

Portable single-camera surveillance system powered from a

 

Surveillance

storage battery or from the mains. It comprises a camera, a

 

Portable

 

video terminal, an electronic unit DCM14, and a set of storage

 

 

 

 

batteries. With the batteries fully charged, the system can

 

 

 

 

operate for up to 100 days. Complete with a 660 Mb card, the

 

 

 

 

ALIP system can record 40÷50 thousand images. It is installed

 

 

 

 

in easily accessible places.

 

 

 

 

 

ALIS

All

in

One

Single-camera surveillance system powered from the mains

 

Surveillance

and built around an electronic DCM14 unit. It has an interface

 

 

 

 

with the inspector’s terminal. The information storage capacity

 

 

 

 

is the same as that of ALIP. It is installed in easily accessible

 

 

 

 

places.

 

 

 

DSOS

Digital Single–

Surveillance system built around a DCM14 unit. The camera

 

Camera

 

may be installed in difficult-of-access places.

 

Optical

 

 

 

Surveillance

 

 

 

 

 

 

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Table 3.2 (continued)

System

System name

Application and features

 

desig-

and type

 

 

nation

 

 

 

 

Multi-camera surveillance system with a tape-recording function

 

FTPV

Fuel Transfer

Underwater closed-circuit video surveillance system with a

 

 

Video

camera in a waterproof shell. It is used for monitoring fuel

 

 

 

handling in pools.

 

MOSS

Multi–Camera

The system can comprise up to 16 video cameras. Information is

 

 

Optical

tape-recorded. By 2006, the system was to be replaced by an

 

 

Surveillance

advanced digital DMOSS system.

 

 

System

 

 

MXTV

Multiplex TV

Multi-camera surveillance system (with up to 16 cameras). It

 

 

Surveillance

will be replaced by a digital server-based system SDIS.

 

 

System

 

 

VSEU

Video System

Multi-camera surveillance system in use by Euroatom.

 

 

Multiplex

 

 

VSPC

Video System

Closed-circuit system which can have up to 4 video cameras.

 

 

Digital multi-camera surveillance systems

 

DMOS

Digital Multi–

Digital multi-camera (normally with 6 to 16 cameras) system for

 

 

Camera

unattended operation and remote monitoring. It is built around a

 

 

Optical

DCM14 unit and has a central console. Each camera is polled by

 

 

Surveillance

the server. Images and data are stored on a portable medium.

 

SDIS

Server Digital

Digital server-based multi-camera surveillance system built

 

 

Image

around a DCM14 unit, which collects images and data from

 

 

Surveillance

cameras (up to 6). It can be also used for checking electronic seals

 

 

 

VACOSS. The server can sort images and data and transmit them

 

 

 

to the Agency offices. The system is fitted up with an

 

 

 

uninterruptible power supply unit which can support continuous

 

 

 

operation of the system for 48 hours in the event of loss of power

 

 

 

from the mains.

 

 

 

Data survey systems

 

GARS

General

Advanced software for viewing video-recordings. It is widely

 

 

Advanced

used for analyzing recordings of many video systems, such as

 

 

Review

ALIP, ALIS, DSOS, DMOS, SDIS, etc. It provides a user-

 

 

Station

friendly interface for examining video-recordings and performs

 

 

Software

a whole number of auxiliary functions. GARS enables an

 

 

 

inspector to make sure that the recordings are authentic, to view

 

 

 

simultaneously images from several cameras, to detect changes

 

 

 

in the monitored surroundings, to decode data, etc.

 

MORE

Multi–system

The station is used by inspectors to examine video-recordings

 

 

Optical

made by MXTV and MOSS systems. Every station of this type

 

 

Review

includes a computer to start programs of the MORE system, a

 

 

Station

monitor with functions of automatic detection of changes in the

 

 

 

conditions, videotape recorders to examine video material, and a

 

 

 

printer.

 

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Means of containment. The purpose of seals is to provide evidence of any unauthorized attempts to get access to the protected material. Seals will also serve for unique identification of protected containers. Disposable metallic, adhesive, fiber-optic, ultrasonic, and reusable electronic seals are used by the Agency personnel, depending on their specific purpose. Seal types are briefly characterized in Table 3.3.

Table 3.3

Sealing devices applied in the safeguards-related activities of the IAEA

Seal de-

Seal type

Application and features

signation

 

 

CAPS

Metallic,

Widely used for sealing casks, cabinets and

 

disposable

equipment of the Agency. This seal is of simple

 

 

design, inexpensive; it is easily applied and removed.

 

 

About 20 thousand such seals are used annually.

VOID

Adhesive,

Made of material destroyed in removal. The seal is

 

disposable

used for temporary containment of material (for

 

 

several hours).

FBOS

Fiber-optic seal,

Unique owing to the random pattern of fibers. This

 

disposable

general-purpose seal is examined by an inspector in

 

 

situ.

ULCS

Ultrasonic seal,

Unique seal checked in situ. Used for sealing casks

 

disposable

with CANDU fuel, kept underwater.

USSB

Ultrasonic sealing

Used for sealing casks with spent LWR fuel, kept

 

bolt, disposable

underwater.

VCOS

Variable coding

Its memory unit saves every act of breaking and

 

seal, electronic,

closing the fiber-optic circuit. Used in conditions of

 

reusable

long-term surveillance of periodically accessible

 

 

objects.

Non-destructive examination of non-irradiated nuclear materials. Most materials covered by the IAEA safeguards are γ–active. Their radiation spectra show distinct lines typical of certain γ–emitting isotopes. The energy characteristics of observed spectrum lines of a material serve as a basis for identification of isotopes and, in combination with line strength measurements, allows estimating the material quantity.

Today, there are commercially available efficient instruments for analyzing γ–radiation spectra. For example, the Inspector’s Mu lti-Channel Analyzer (IMCA) employs the technology of digital signal processing and

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can operate together with various detectors made of: high-purity germanium (HpGe), cadmium telluride (CdZnTe), and sodium iodide (NaI), which afford high, medium and low energy resolution. There is also a design option of a Miniature Multichannel Analyzer (MMCA). This instrument is much smaller and lower in weight than the previously employed Portable Multichannel Analyzer (PMCA) and, into the bargain, has three times longer time of continuous operation when powered by storage batteries.

The International Agency uses in its inspections a number of γ– spectrometers which differ mostly in their resolution as well as in the capability for subsequent information processing. Many of these spectrometers comprise the above multichannel analyzers. These instruments are briefly described in Table 3.4.

Table 3.4

Gamma–spectrometers in use by the IAEA in the safe guards-related activities

System

System name

Application and features

designation

and type

 

HM–5

Hand–held

Modern hand-held digital gamma– spectrometers

 

Assay Probe

allow determining dose rates, finding radiation

 

 

sources, determining the active length of fuel rods

 

 

and assemblies, and detecting the presence of U

 

 

and Pu. The base option of this instrument includes

 

 

a NaI detector. For special applications, a CdZnTe

 

 

detector can be hooked up. It can store up to 50

 

 

spectra (1024 channels for each), which are entered

 

 

into a computer for subsequent processing.

IMCN,

Based on the

With an HpGe detector (IMCG), it is a

IMCC,

IMCA

spectrometric device of high resolution. It is used

IMCG

analyzer

for determining U enrichment and isotopic

 

 

composition of Pu.

MMCN,

Based on the

In a combination with a CdZnTe detector (MCC)

MMCC,

MMCA

and a notebook (Palmtop), it is a portable (small

MMCG

analyzer

enough to be carried in an ordinary briefcase),

 

 

powerful and flexible spectrometric system suitable

 

 

for many inspection purposes.

The technique of neutron coincidence counting is a robust and accurate method which is widely used for determining the content of Pu and U235. Modern well-type systems of neutron coincidence counting can process

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Источник: https://studfile.net/preview/16708779/