Requirements of Tracking System for Radioactive Materialskepic.org/kepic_week/sub2/download.php?filename=tt... · Better Standards, Better Life 박태순 : [email protected] 3 Introduction

Requirements of Tracking System for Radioactive Materials

박 태 순 (주) 덕인, 연구위원

2 박태순 : [email protected] Better Standards, Better Life

Contents

1. Introduction

2. Scope

3. Tracking System

4. Transportation of Radioactive Materials

5. Radioactive Materials to be Transported

6. Container

7. Measurement Devices

8. Guardian Devices

9. Control Center

10. Security & Qualification


Introduction

Radioactive materials are widely used in the industrial non-destructive

testing, medical therapy, and nuclear facilities, etc., and the safety of

radioactive materials are very important to protect threatening to the public

health.

It is required that a tracking system for radioactive materials should be

installed to localize their positions, monitoring their usage, and so on. The

tracking system includes two functions namely a detection of radioactive

materials and wireless communication.

In addition, transport safety and security are vital during all stages of the

nuclear fuel cycle, such as transportation of uranium fuel assemblies,

radioactive waste, spent nuclear fuel.


Scope

International Standard specifies the requirements of tracking system for

radioactive materials and may also be used for the supplementary guidance

to the regulatory body.

The tracking system consists of a measurement unit and a wireless

communication unit.

- The measurement unit shall include a radiation monitor which measure radiation

dose (or dose-rate), temperature and pressure sensor.

- The wireless communication unit shall include mobile devices, base transceiver

systems and mobile service providers. And it shall localize the position of the

radioactive materials transported using global navigation satellite system (GNSS)

and code division multiple access (CDMA).

Radioactive materials to be tracked include all radioactive material

(radioactive sources, radioactive waste and nuclear material including

nuclear fuel and spent fuel) which is transported using a Type B(U), Type

B(M) or Type C package. And other criteria might be considered when the

transport index is greater than 1.


Tracking System-1

This system should receive the location information on a real-time basis of

the radioactive materials using a national or regional communication

networks, and should display the exact location in connection with the

related geographical information.

The tracking system shall be fixed at outer surface of the container rigidly

not to detach with the screws provided. The tracking system network

consists of a remote mobile system, the control centre, a mobile service

provider and users.

The remote mobile system consists of a vehicle, a container, a measuring

device, a communication device including position locator, etc. The control

center plays a role of system operation, data and communication servers,

users and location determination service.


Tracking System-2

Figure 1 – Schematic diagram of tracking system for radioactive materials


Tracking System-3

Detectors

Radiation detector is used to measure dose/dose-rate or photon energy spectrum

at outside surface of the container which contains radioactive materials. Types of

radiation detector used in tracking system are G-M tube, scintillation detectors,

and semi-conductor detectors. Scintillation and semi-conductor detectors are

also used to measure photon energy spectrum as well as dose/dose-rate. Range

of dose-rate to be measured shall be 0.1 μSv/h to 10 mSv/h.

Sensors

Temperature and pressure sensors are used to monitor environmental conditions

outside the container which contains radioactive materials. Measurement range

of the temperature sensor shall be -20 ℃ to 85 ℃.

Local data storage

Data acquired from radiation detector, temperature sensor, pressure sensor, and

other sensors are stored in local data storage for data security and sent to

control center, simultaneously.


Tracking System-4

Data acquisition

- The power supplies for radiation detectors and sensors shall be a part of the

tracking system and provided by the manufacturer.

- The radiation, temperature, pressure, and position measurements should be

acquired by the tracking system.

Communication

- Interface

The communication shall be capable of interfacing with WiFi, CDMA, GNSS or

RFID and should be a mobile device which transmits raw data and receives

commands from the control center.

- Location determination

Location shall be calculated with position data gathering from wireless devices

and gyroscope. The resolution for the location determination should be within

100 m. A mobile device shall provide to determine its location.

- Control center

The control center should provide systems to support tracking systems and

users.


Radioactive materials to be transported-1

Sealed radioactive sources

Sealed radioactive sources which are used in the fields of industrial radiography,

industrial irradiation, medical therapy and others should be tracked.

<For example>

- Ir-192 is one of the most widely used sealed sources for non-destructive testing

(NDT) and put inside of a small container, called type B(U) or B(M).

- Co-60 and Ce-137 are used as sealed sources for medical therapy, calibration of

radiation protection instruments, and industrial irradiation.

- Cs-137 together with Am/Be sources are also used in density gauges.

Since the most of these sealed sources mainly emit gamma rays, the photon

detector contained in the tracking system is used to measure radiation dose(dose-

rate) or energy of gamma rays emitted from the sealed source.


Radioactive materials to be transported-2

Uranium

Uranium (U) is used to produce nuclear energy in nuclear power and research

reactor. In nature, uranium is found as U-238 (992.739 g/kg to 992.752 g/kg), U-235

(7.198 g/kg to 7.202 g/kg), and a very small amount of U-234 (0.050 g/kg to 0.059

g/kg). 235U has the distinction of being the only naturally occurring fissile isotope. 238U is fissionable by fast neutrons, and is fertile, meaning it can be transmuted to

fissile Pu-239 in a nuclear reactor.

Uranium is used as nuclear fuel of power reactor and research reactor. Nuclear

fuel is mostly transported by large containers.

Fissile material

Nuclear fission products are the atomic fragments left after a large atomic nucleus

undergoes nuclear fission. Typically, a large nucleus like that of uranium fissions

by splitting into two smaller nuclei, along with a few neutrons, the release of heat

energy(kinetic energy), and gamma rays. Fissile material usually contained in

spent nuclear fuel shall be transported with fissile material container equipped

with various kind of safety devices.


Container-1

Sealed radioactive source

A sealed radioactive source is typically placed in a sealed protective metal casing

in a transportable device, known as a projector or camera. The projector is

considered as one of the transport containers, typically type B including B(U) and

B(M) in accordance with IAEA regulation. The measurement devices shall be

attached at the outside of container.

The design and condition of type B container is follows:

- Each package for radioactive contents with activity shall be not greater than 105A2

- The ambient temperature shall be assumed to be 38°C.

- A package shall not have a maximum normal operating pressure in excess of a gauge

pressure of 700 kPa.

- A package shall be designed for an ambient temperature range from -40°C to +38°C.

Note, A1 and A2

A1 shall mean the activity value of special form radioactive material which is listed in Table 2 or derived

in Section IV of IAEA TS-R-1 and is used to determine the activity limits for the requirements of IAEA

TS-R-1. A2 shall mean the activity value of radioactive material, other than special form radioactive

material, which is listed in Table 2 or derived in Section IV of IAEA TS-R-1 and is used to determine the

activity limits for the requirements of IAEA TS-R-1.


Container-2

Fissile material

Spent fuel is also placed in a sealed protective metal casing in a transportable

device, known as a container of fissile material. The measurement devices shall

be attached at the outside of container.

Maintain sub-criticality during normal and accident conditions of transport; in

particular, the following contingencies shall be considered:

- Leakage of water into or out of packages;

- Loss of efficiency of built-in neutron absorbers or moderators;

- Rearrangement of the contents either within the package or as a result of loss

from the package;

- Reduction of spaces within or between packages;

- Packages becoming immersed in water or buried in snow; and

- Temperature changes.


Measurement Device-1

Measurement device

- The radioactivity of Ir-192, used as gamma radiography source, is typically 5

TBq, and that of spent fuel is more than several PBq. It may be dangerous for

workers to handle sources, so it should be recognized the existence of the

radioactive material by means of measurement.

- It is known that the radiation influence to normal certified container is

negligible, but unexpected radiation level should be monitored by means of

radiation measurement using a portable device. Measurement device should be

capable of checking the status of radioactive material and its container, and

consists of a sensor and its supporting electronics.



Sensor

- A radiation sensor should be installed at outside of a container to measure

radioactivity, and may be able to identify nuclides as well as radiation

dose.

- A sensor detecting leakage of radiation should be rigidly attached on or

outside of a container, or it should be a sensor at least to monitor

open/close state of the container.

- The temperature inside the container may be monitored continuously.

- The position detection devices using WiFi, GNSS or RFID shall be installed

at the surface of the container.



Electronics

- The device should be capable of providing sensor power and measuring

parameters including radioactivity or on/off state of a container, by either using

analogue or digital technology.

- The device shall be supplied its own operating power during transportation.

- The device shall be provided to monitor the measuring parameters and to

calculate this parameter, if required.

- The device should be included a way to monitor the associated sensors’ integrity

and their alarms.

- The device shall be provided the measured or monitored data to a mobile device.

- The device shall be able to withstand the environmental conditions during

transport.


Guardian Device-1

Mobile device

- The mobile device should meet with protocols of the location determination

service covered with international, national or specific regional wide.

- The mobile device should be able to receive the request of location

determination service to register its information regarding to the global

position, status, container, etc. of the transportation and control commands.

- The mobile device should be installed a tracking function using a cellular

phone, GNSS chip, RFID (radio frequency identification) tag or bar code.

- The mobile device should be able to transmit the information on request from

the location determination service and execute control command received.


Guardian Device-1

Mobile device

- Location based services may be applied to the configuration of the tracking

system and control center, and may be used to determine the position (or physical

location) of the tracking system.

- The component of position determination shall be composed of a tracking

services, navigation, routing, addressing, network, feature data and data types

such as voice stream, binary data, map or image.

- The data recording device should be available locally in the mobile device and

operating independently from any wireless connection to ensure a complete

logging history.

- Data logging should be provided so that the mobile device is possible to log

information such as:

• authentication and connection attempts,

• maintenance data (battery wear, CPU load, auto-test results, etc.),

• system-specific process data (temperature, pressure, vibration level, etc.).

- These data should be accessible for a cybersecurity audit in case of a suspected

cybersecurity event.


Guardian Device-2

CCTV

CCTV may be used for recording on the circumstances of transportation, and

send image data to control center, when unwanted event occurs.

Meteorological status

Meteorological information may be revised, periodically.

Power provision for tracking system

- Power supply should be provided to operate a measuring device for at least one

week. The power of a measuring device may be shared with power supply of a

mobile device or a container.

- Any measuring device should be operating at a lower potential voltage. Any

sensor or instrument should be a device of the lowest power consumable.

Battery level of devices running on batteries shall be monitored.


Control Center-1

System operation

- It should be possible to monitor the characteristics of a radioactive material

and its status.

- It should continuously be traced the location of a remote mobile system, and

should be identified its pathway.

- It should be possible to set the periods of data transfer.

- It should be able to control a remote mobile system, at an emergency.

- It should be provided to service to trace on the location of a radioactive

material.

Database server and data communication server

- Communication server should be capable of receiving status and location

information for mobile devices.

- It should be provided in the database server to log and maintain the

information of GIS and radiation source at a mobile device which attached on

or outside of a container.

- Database server should be capable of providing the information on location

information interfaced with GIS, mobile devices and radiation sources.


Control Center-2

Operation

- The user should be able to inquire the location of a radioactive material and the

status of a remote mobile system, with an internet.

- The user should be able to access the actual position and status information of

the tracking system as well as the complete history of the transportation

process via remote wireless connection.

Location determination service

- Location determination service should be used with one of mobile service,

internet service, or radio frequency (RF), RFID or hybrid of these technologies.

- Location determination service should be provided such functions as the

request of status information according to mobile device and its GPS

information.

- Location determination service should provide functions such as calculation of

its location, transmit control command to a mobile device and transmit

information according to location of mobile devices to servers in control center.


Security and Qualification

Security

Physical security

Wireless devices shall be protected by a solid covering or grid in order to prevent

from damage or unauthorized access. Those devices shall be installed to hardly

access from outside.

Data security or cyber security

Tracking system including mobile devices and the control centre should be

planned, designed, implemented and operated in accordance with ISO/IEC 27000-

series, and more specific requirements


Security and Qualification

Qualification

Measurement device

- A measurement device should withstand vibration, shock, temperature,

humidity and radiation exposure at around its environment.

- Any software in a measurement device should be developed following

software lifecycle.

- Measurement device should be periodically calibrated.

Mobile device

A mobile device should withstand vibration, shock, temperature, humidity

and radiation exposure at around its environment.

Documents

Requirements of Tracking System for Radioactive Materialskepic.org/kepic_week/sub2/download.php?filename=tt... · Better Standards, Better Life 박태순 : [email protected] 3 Introduction