The gamma detection system essentially comprises of 2 large volume of plastic scintillation detectors housed inside each detector pillar. Each PVT detector has an active volume of 22400cc. Each gamma detector is provided with necessary lead shielding to minimize the background and to enhance the MDA of the system.

The gamma detection assembly is housed inside aluminized material based detector pillar. Two such detector pillars are placed along either side of the passage from where the vehicle is going to pass. This installed monitor automatically detects the presence of radioactive material being transported in vehicles if it exceeds preset levels. The monitoring system does this by measuring the radiation level taken while vehicle occupies detection area and comparing this level to the background radiation level that is measured and updated while detection area is unoccupied.

The background radiation levels are continuously measured and automatic adjustment of alarm thresholds enables a constant statistical false alarm rate to be maintained during the system use. Occupancy sensors are used to detect the presence and absence of vehicles as it passes through the monitor to know when to monitor the background and when to monitor the vehicle. The sensitivity of detectors is dependent upon the closeness of the detector and source as well as the slowness with which they pass across the detectors. For large trucks and vehicles, large volume detector pillars are recommended and maximum distance between pillar is 3.5m. Additionally barriers are to be provided for the detectors to protect monitor from being damaged by vehicles.

The detector needs to be placed where speed of the vehicle is controlled and reduced. The speed of the vehicle should be less than 4kmph and the vehicle should not stop while passing through the monitor. The performance and effectiveness of the installed instrument is strongly dependent on its ability to measure radiation intensity over the search area of interest. As such based on this requirement detector volumes, geometry and dimensions have been adopted.

Alarm indications and displays are available locally and are clearly visible to the officers manning the inspection point and are also available remotely at the central monitoring PC. This system could be installed at various entry/exit points of the vehicles and can be under the supervision of security officer.

• Uses 2 / 4 no. of large volume plastic scintillation detectors.
• Uses State-of-Art SBC and FPGA Technology in the data acquisition unit.
• Ethernet port has been provided for connectivity to plant wide LAN / PC.
• Automatic / manual mode of vehicle scan supported.
• Designed to meet ANSI N42.35 specification.

(A) GAMMA DETECTION SECTION

Detectors Type:	High sensitivity PVT detectors coupled to PMT detector
No. of detectors per pillar:	1. Detector / pillar for TR1021 2. Detector / pillar for TR1025 / TR1030
Volume of each detector :	18000cc
Dimensions of each detector:	1200 x 380 x 40mm
Energy range:	30 KeV to 5 MeV
Sensitivity of each detector:	400 CPS/mR/h (Approx)
Shielding :	Suitable thickness lead shielding is provided on all sides of detector except the measuring face to suppress background radiation and to enhance MDA.
High voltage and front-end electronics:	High voltage and front-end electronics are all housed together in each of the detector pillar.

B) MEASUREMENT & ALARM UNIT:

This unit comprising of advanced electronic circuits with embedded code built-in to receive data from the gamma detector assembly and correct for background levels and generate audio/visual alarms in the event counts due to vehicle monitoring exceed the preset levels set. Alarm data is automatically transferred at the end of monitoring to the central PC along with the photograph of the vehicle for further investigation by the duty personnel.

Background Updation:	Automatic background measurement by sensing the detection area is unoccupied by using occupancy sensors.
Alarm Setting Adjustment:	Automatically adjusted based on the current background level.
No. of monitoring channels:	2 (TR1030) / 4 (TR1039).
User Interface:	Front panel keypad (password protected) or through PC.
Measurement Unit:	CPS.
Measurement Range:	0 to 99999 CPS.
Alarm Range:	0 to 99999 CPS.
Occupancy Sensing:	Using IR/proximity sensors to detect vehicle presence.
Detection Area & Performance criteria:	Vertical : 2.5mtrs.(TR1030) or 5mtrs.(TR1039).
Horizontal :	0 to 550mm.
Speed of Vehicle :	0-4 Km/h.
Audio/ Visual Alarms:	Hooter and sounder have been provided for the purpose of generation of audio/visual alarms.
Radiation Performance Standard:	Better than ANSI N42.35.
Vehicle Identification (optional):	This can be done by entering the vehicle number in the report generated by TMS Software.
PC connectivity :	Through RS232 cable,data can be transfered from Control unit to PC.

(C) COMPUTER SOFTWARE & PC CONFIGURATION:

The data acquisition and control application software running on the host PC with a WINDOWS XP OS will communicate with the processing electronics through Ethernet port. This software facilitates remote configuration of parameters, live acquisition of data and analysis of profile for localization of any contamination. The software is extremely flexible allowing the user to easily configure the system general operations like adjustment of detector parameters and accessing of database of all the individual vehicle scans. The software is so designed that it does not require the duty personnel to understand physics to operate the equipment.

PC Configuration : Standard PIV configuration with WINDOWS XP/2000 operating system (PC not within scope of supply).

System operating conditions :

Analog output : 0-5 volts for full range.
Contact output : Potential free contact output provided for detected contamination for gate control.
Power supply : 230 /-10% Volt AC.
Temperature : 0 to 60⁰ C.
Humidity : Upto 95% RH.
Environment Protection : IP-54.

Performance specifications & detection capability :

The truck monitoring system manufactured by Nucleonix will detect reliably very low levels of contamination which may be present in the vehicles carrying verity of scrap material. This system will reliably detect any contamination producing an exposure rate of 10mR/hr or 0.1mSv/hr a point source placed on the moving vehicle traveling at a speed of about 8 kmph. Detection capability will increase with decrease in speed.

Integration with cargo scanner:

This system integrates cargo scanner of smiths detection to provide integrated report.

Minimum Detectable Activity :

MDA is computed @1 sec counting time from when the following sources are kept @ 1 meter distance from the middle of detector assembly.

Source	MDA
Cs-137 Co-60 Ba-133	90 k Bq 60 k Bq 90 k Bq

Note : Two such detector pillars are installed on both sides of the path way for the trucks carrying scrap metal or container with scrap metal.

SOFTWARE SPECIFICATIONS :

SYSTEM REQUIREMENTS:

PC (Minimum configuration): Intel i3 CPU or better, 2 GB RAM, 160 GB HDD.
OS: Windows 7. (Windows Vista / XP is not supported)
Antivirus: Norton / Quick heal / Kaspersky
Internet connectivity & Team viewer software: For remote trouble-shooting COM port / USB-Serial convertor: For connecting Electronic Unit to PC.

INSTALLATION:

To install the software, execute TMS.bat in the installation CD. Click through the options, until you get the message that installation is completed successfully. In case of any errors, please take a screenshot of the error message and email to Nucleonix Customer Support.

CALIBRATION:

After installation of the system, it is calibrated by Nucleonix Engineer by generating Profiles for trucks of various Models, Makes, Lengths and Heights. The data related to trucks are stored in a Calibration file. For every acquisition, TMS Software shows the available calibrated Truck profiles & asks the User to select the Truck profile. This data is used in reports to arrive at a logical conclusion on Contamination. Details are given in Appendix A. Re-Calibration is required every 1 year.

After making connections, the COM port number must be identified. For this, Right click on My computer icon on Desktop. Select Properties – Device Manager – Ports. You will find the COM port number. For eg. If you find COM3, it means that COM port number is 3.

EXECUTING THE APPLICATION:

A separate TMS Software has been designed in such a way that it provides accurate results and this will be provided along with the Personal Computer.

Report Generation Criteria

Interpretation of Reports

Given below is a sample report for a truck carrying steel scrap which is contaminated. Notice the Alarm Status row, which shows that data from detectors D1, D2, D3, D4, ‘Avg of all detectors’, ‘Sum of all detectors’ – is contaminated. Notice the % Fall row, which shows that there is an increase of 3.75% in average readings from all detectors for this truck. This again implies that there is contamination. Now notice the Spectrum data Section – ‘Sum’ column. There are several continuous readings which have crossed statistical limits of 3 Sigma (indicated in RED), which again suggests Contamination. Look at the Statistical Observations section. The Sum row shows that ‘Total Events Score’ and ‘Events in Sequence Score’ are both high, which indicates contamination. (Event is the case when current data value exceeded Sigma or 2 Sigma or 3 Sigma.

Let us now analyze another report shown below, which has much lower contamination: Notice the Alarm Status row, which shows that data from detectors D1, D2, D3, D4, ‘Avg of all detectors’, ‘Sum of all detectors’ – is contaminated. Notice the % Fall row, which shows that there is an increase of 1.45% in average readings from all detectors for this truck. This again implies that there is contamination. Now notice the Spectrum data Section -‘Sum’ column. There are 4 continuous readings which have crossed statistical limits of Sigma (indicated in GREEN) & 2 Sigma (ORANGE), which again suggests Contamination. Look at the Statistical Observations section. The Sum row shows that ‘Total Events Score’ and ‘Events in Sequence Score’ are both high, which indicates contamination. (Event is the case when current data value exceeded Sigma or 2 Sigma or 3 Sigma).

Help Menu

Clicking on this command this file is opened. In case there are any upgrades to the software, ask Nucleonix for the latest version of ‘TMS Software User manual’. Copy it to the same folder as TMS application.

Maintenance and Customer Support

Periodic functional checks of system must be performed with Check source as frequently as possible, as per procedure given in Appendix B. This can be done by Customer’s trained employees. Apart from this, PC must be kept free from Virus and backed up by UPS power. Calibration must be performed every 1 year. You may contact us 1 month prior to completion of 1 year. Customer must enter into Annual Maintenance Contract after Warranty. This will entitle them for preventive maintenance checks, software upgrades, Re-Calibration, etc.