The new radiation safety control system of GANIL and its extension
to the rib SPIRAL facility
T.T.Luong, J.C.Deroy, P .De Saint Jores, L.Martina
Grand Accélérateur National d’Ions Lourds
BP 5027 - F 14 076 Caen Cedex 5, FranceAbstract
A new generation of radiation safety control system
was carried out . Extending this VME-based system toencompass the forthcoming rib (radioactive ion beam)
SPIRAL facility is in progress. This extension is being
developed along several directions : hardware andsoftware upgrades, graphical user interface enhancement,
communication shielding, access badge system renewal.
Requirements and choices are discussed. Results arepresented.
1. Introduction
A major extension of the accelerating installation
GANIL , named SPIRAL, is under construction to be
operational in the year to come. The SPIRAL facility istargeted to on-line production and acceleration ofradioactive ion beam, taking advantage of the Very HighIntensity facility currently underway. SPIRAL features anenergy range from 2 to 25 MeV per nucleon and intensityfrom a few pps to 108 pps. It will induce challenging
condition for operation and for radiation safety control.
The radiation safety control systems provides means
and ways to avoid radiological hazards for individuals in
the accelerator rooms and experimental areas, as well as
in the the storing room of actived devices.
The second generation control system currently in use[1] is being extended to take into account the SPIRAL
facility. This extension in term of equipment is roughly
one third of the existing installation. The system has tomanage four additional gating locks, doors and sevencontrolled rooms ( e.g. the Target Ion Source System TISS
room , the cyclotron CIME room) distributed over twolevels.[2]2. The radiation safety control system
A schematic layout of the radiation safety control
system is shown on Fig.1. Its different subsystems areemphasised hereafter.
2.1. Access control
Access control aims at averting radiological risks for
personnel who attempts to enter a zone under control(noted ZC ) of the INB (nuclear base installation) site.
Beam penetration into a ZC is interlocked by generalconditions of the room and its radiological level measured

with specific detectors. It is achieved by mastering at least
two upstream beam safety devices (e.g. beam stopper,bending magnet or accelerating RF device).
The operation of the SPIRAL facility will induce
severe conditions for the access control, since different
experimental modes may intricately exist : the current
GANIL accelerator and SPIRAL may operate separately
for stable ion beams, or they may operate in cascade as a
joint accelerating complex with production, accelerationand experimentation of radioactive ion beam.
The control system achieves access control andreporting (online graphical display and event storing) aswell. It is composed of two subsystems :n a centralised and master subsystem named UGS2. It
manages the databases of detectors and id-badges,
checks the current status of the ZC and its
radiological level and makes decision for accessauthorisation to be notified to the local gatingcontrollers.
n local gating controllers named UGD are distributed
along the accelerator and experimental gating locks
for local access control. Each UGD is designed totake care of up to two ZCs.
UGS2 and UGD make use of VME standard processors,
I/O and drive modules. Its application software runs under
the pDOS operating system supplied by Eyring which
provides services for real-time multitasking. The UGS2
software is built around an event bus. There are about
one hundred event triggered tasks sorted into I/O tasks,
processing tasks and ancillary tasks.
Access control will rely on the up-coming renewed idbadge control system. A contact-less badge with credit
card format is adopted for robustness and compliancewith the ISO standard. This badge shelters powerless
chip, memory and an RF loop which are energised byinduction, while reading.
Opportunity was taken to renew the campus access
control with a derived technique. A Central Platform will
provide a user friendly environment to produce
personalised badges with id- and clearance- information(zones and time slices authorisation, ..), to manage thecentral badge database, to initialise and update the local
databases of badge readers, to supervise the access ongraphical colour screen, to log accesses with status and toprovide whenever needed statistics. The Central Platform
and badge readers will communicate via the LONWORKS
fieldbus.

n The hub. This device centralises synchronous data

2.2. Radiological Control
Radiological level mapping is achieved by specialised
detectors (neutron, gamma, gas) installedin the vicinity of the accelerator and experimental area.
The laboratory is meshed by about one hundred detectors
including 25 detectors for SPIRAL. The radiologicallevels are measured every three seconds.
The sampled data are collected by dedicated VME
modules for processing and concentrated into 6 VME
cubicles named UDE. The UDEs are linked via theprivate Ethernet to the Central Control console for further
inspection, processing and long term logging. The UDEs
are also wired to the UGS2 system for radiological level
condition interlock.
2.3. Central Control
The Central Control provides the operator interface
services for on-line and off-line operations : dataprocessing and display on colour graphical console unit,
data management (archiving and retrieval, sorting,presentation, ..) [3]
The Central Control system is composed of two parts,
structured around a private Ethernet LAN :Central Control

collected by the radiological control and potentially via the LAN bridge- events from the Access Control aswell as information from the Accelerator controlsystem (e.g. beam parameters, acceleration
conditions).
Also, the Hub is in charge of data filtering and storing of
raw and processed data for short term presentation. Long
term logging or archiving of data and events is an
important issue in safety control, since information mustbe traced back over a ten year period .
n The GUI. User interface makes use of 21’ large colour
screen workstations and provides operators a
comfortable environment to ease observation anddecision. As examples of available services : -The
radiological levels sampled over the INB site can bedisplayed at will in graphical synoptics or in alphanumerical presentation, both with real-time update. The memorisation of maximal level reached by everydetector is a sampled-and-hold system with colour
coded display for early warning of operators, Plotting the radiological level as a function of timewith automatic time scaling, for evolution watching,
may take into account up to three detectors.

Access Control
locks
PrinterPrivate Ethernet

UGS2

UGD
UGD
Beam Safety
DevicesHub

Printer

BridgeData Management& Processing
ArchiveUDE
UDE
Radiological Control

General Ethernet LANFig.1 Schematic layout of the radiation safety control system

Neutron-,Gamma- ,GasDetectorsTechnical choices are guided by security of operation,
homogeneity in hardware and software to target
compatibility and adoption of open standard for easy andcost effective evolution. The VME standard is therefore
adopted. Applications are written in C language and run
under the UNIX real time operating system LynxOS
which complies to the POSIX standard. Hewlett Packard
workstations are used for GUI with Motif/Xwindow andprogramming was carried out with the uims (userinterface management system) XFACEMAKER fromNSL. Archiving medium is CDROM suitable for six
month operation .
Also a backup system is presently operating in parallel.
Its is based on a PC microcomputer operating underLynxOS.

M1

Communication relies on Ethernet LAN and TCP/IPprotocole , NFS, etc.. The radiation safety control system
is hooked to a private Ethernet LAN which provides abackbone communication medium. Bridging this private
LAN to the General Ethernet LAN of the GANIL willallow filtered information interchange with other systems(e.g. accelerator control system), following TCP/IPprotocole.
To shield more securely the UGS2 against intrudingcommands, its VME CPU1 is not directly hooked to theLAN but ‘screened’ by a second VME CPU2 . CPU2
which shares the same crate as CPU1 is linked to theEthernet LAN for filtering mission with limited readcommands allowed (Cf.Fig.2).
3. Current status

MiA subset of the radiation safety control system is built
up to control the first tests of the cyclotron CIME. On site
installation of hardware and software is underway.
The Central Control System is currently in operationfrom the onset of this year.
The extension of the control to SPIRAL is scheduledfor the year to come. Hardware is in progress, software
will be designed within the quarter to come. The newbadge system is expected for spring’98.

General Ethernetbridge

2.4. Communication

HubPrivate Ethernet

4. References

UDE 6
UDE 6

UGS2
CPU 1

CPU 2

UGD

UGD

UGD

111

Fig.2 :Shielding the UGS2

[1] P.De St Jores, T.T.Luong, L.Martina, G. Vega,‘A new radiation safety control system for GANIL’CTDCA, Calcutta, India, Nov. 1991
[2] T.T. Luong, J.C.Deroy, P.De St Jores, L.Martina‘Radiation Safety Control of Spiral’, SPIRALITC Reports January and May 1995, Oct 1993
[3] T.T. Luong and al, ‘User requirements of theCentral Control System of the Radioprotection’(in French), GANIL Rep. N°508.94, Jan. 1994
P.Cariou, P.De St Jores, ‘Central Control GraphicalInterface - User Manual’ (in French),GANIL Rep N° 10.95, 1996