Johnson Matthey TRACERCO T401 User manual

TRACERCO T401
Contamination Monitor
USER MANUAL

Quality Assurance
Tracerco UK has accreditation for ISO9001 and ISO14001.
Confidentiality Notice
Information contained in this publication or as otherwise supplied to Users is believed to be accurate at time
of going to press and is given in good faith, but it is for the User to satisfy itself of the suitability of the Product
for its own particular purpose. Johnson Matthey plc (JM) accepts no liability for loss or damage (other than that
arising from death or personal injury caused by JM’s negligence or by a defective Product, if proved) resulting
from reliance on this information. Freedom under Patent, Copyright and Designs cannot be assumed.
Copyright © 2017 Tracerco Ltd. All rights reserved.

Table of Contents
1General Description.................................................................................................................................... 5
2Operational Safety...................................................................................................................................... 6
3Post Delivery Checks ................................................................................................................................. 7
4Operational Features.................................................................................................................................. 8
4.1 Switch On............................................................................................................................................8
4.2 Speaker...............................................................................................................................................8
4.3 Backlight .............................................................................................................................................8
4.4 Low Battery.........................................................................................................................................8
4.5 Pre-Set Alarm .....................................................................................................................................8
4.6 Detector Probe....................................................................................................................................9
4.7 Calibration...........................................................................................................................................9
5Measurement of Radiation Contamination............................................................................................... 10
5.1 Procedure .........................................................................................................................................10
5.2 Bargraph Display..............................................................................................................................10
5.3 Digital Numeric Display.....................................................................................................................10
5.4 Peak Display.....................................................................................................................................10
5.5 Mode / Select....................................................................................................................................10
5.6 Nuclide Calibration Selection............................................................................................................11
5.7 Carry Out a “Background” Count ......................................................................................................11
5.8 Carry Out a “Nuclide Measurement”.................................................................................................12
5.9 Nuclide Options ................................................................................................................................13
5.10 Operational Ranges..........................................................................................................................14
5.10.1 T401 Functional Diagram ........................................................................................................ 14
5.11 Setting Alarm Trip Levels..................................................................................................................15
5.11.1 Sounder Options...................................................................................................................... 15
5.11.2 Setting the Alarm Trip Level .................................................................................................... 16
6Detector Probe ......................................................................................................................................... 17
6.1 Probe Retained in Monitor Yoke.......................................................................................................17
6.2 Remote Probe / Yoke Assembly.......................................................................................................17
6.3 Remote Probe with Telescopic Extension Kit...................................................................................17
7Maintenance and Calibration.................................................................................................................... 18
7.1 Battery Replacement ........................................................................................................................18
7.2 General Maintenance .......................................................................................................................18

7.3 Repair and Calibration......................................................................................................................19
7.3.1 Calibration Plaques...................................................................................................................... 19
8Technical Specification............................................................................................................................. 20
9Monitor Response .................................................................................................................................... 21
9.1 Affects of Gamma Radiation.............................................................................................................21
10 Hints for Radiation Contamination Monitoring.......................................................................................... 22
11 Health and Safety..................................................................................................................................... 23
11.1 Training.............................................................................................................................................23
11.2 Battery life.........................................................................................................................................23
11.3 Probe ................................................................................................................................................23
11.4 Radiation reading..............................................................................................................................23
11.5 Alpha radiation...............................................................................................................................23
Revision History............................................................................................................................................... 25

1 General Description
The Tracerco T401 is a portable battery operated radiation contamination monitor, capable of
measuring alpha, beta and gamma radiation over a wide range of energies. Radiation detection is
carried out using a thin window Geiger Muller Tube located in a detachable probe adjacent to the head of
the monitor.
Tracerco has extensive experience of the practical difficulties which may be encountered when
attempting to carry out contamination monitoring of both man-made and naturally occurring
radioactivity under hostile and restrictive environmental conditions, particularly those which relate to
the Chemical, Mining, Nuclear and Oil and Gas Industries.
The Tracerco T401 has been designed to address many of these practical issues in providing a
monitor which is reliable, versatile, easy to use and capable of operating in adverse environmental
conditions.
A key feature of the Tracerco T401 is the capability to allow pre-programming of detection efficiency
data for a wide range of radionuclides enabling recorded counts/sec to be automatically translated
into more radiologically significant units of Bq/cm
2
. There are additional design elements which are
fully described in this manual and combine to make the T401 an invaluable instrument for use in
radiation contamination monitoring.

2 Operational Safety
The Tracerco T401 Contamination Monitor is a portable battery operated device which has been designed
to exacting standards to operate reliably in adverse environments.
Typical battery life is around 100 hours. A ‘LO BATT’ warning appears on screen when the residual
capacity reduces to about 4 hours. When the residual charge is exhausted, the screen clears.
A selectable backlight facility allows measurements to be made under dark or low light conditions.
(Note that the extended use of this function will significantly reduce battery life).
An audible response is also available to complement visual measurements.
In the event of a GM tube failure or circuit malfunction which interrupts the radiation detection
signal, the screen will indicate the following warning message “ERR1”.

3 Post Delivery Checks
All monitors supplied by Tracerco have been fully inspected, tested and calibrated prior to shipping. The
monitor will be fitted with a new battery and available for immediate operation.
Each monitor is supplied in a protective overpack for transportation (customers may purchase an
alternative, special transport and storage case).
All monitors should reach the customer in perfect working order.
In the unlikely occurrence of a problem, please contact Tracerco immediately (contact numbers are
provided within this manual).
PLEASE ENSURE THAT THE MONITOR RADIATION TEST AND CALIBRATION
CERTIFICATE IS PRESENT IN THE PACK. (Certificates should be filed in a safe place for future
reference. In the event of difficulties, duplicate certificates can be provided by Tracerco free of
charge, they are also available on our webtracker.

4 Operational Features
Owners should also refer to the Main Menu Structure for Functionality
4.1 Switch On
The monitor is activated by pressing the RED on / off switch. This switch has a toggle action –press for
ON and press again for OFF .In the absence of any significant local radiation sources the meter will
register incident background radiation which will vary with geographical location. A typical background
reading on the monitor would be of the order of 0.5 –1 count per second.
Please note that there may be a slight delay of one or two seconds between physically operating the
switch and the screen clearing of information.
4.2 Speaker
Pressing the GREY switch with the speaker symbol activates the internal speaker. The speaker provides
an audible clicking sound whose rate is proportionate to the amount of radiation registered by the
detector.
The speaker may be silenced by re-pressing the GREY switch. The speaker symbol shows on
screen when the audible option has been selected. Battery life is extended with the speaker off.
4.3 Backlight
The monitor display is fitted with a backlight, which is available for use in situations of low ambient light
intensity. The GREY switch with the sunburst symbol is pressed to activate the backlight facility. Since the
backlight significantly increases the current drain on the battery, the pushbutton switch is designed for
contact operation only ie., depressing the switch activates the backlight and releasing the switch cancels
the light.
4.4 Low Battery
The monitor is equipped to display a “LO BATT” message. Although it is recommended that the battery be
replaced as soon as this message is activated, it might be expected that under normal conditions, the
monitor is capable of operating for a further 4 hours.
4.5 Pre-Set Alarm
The monitor is equipped with an alarm function which the operator can pre-set, within prescribed
limits, to any desired level of counts per second ( cps ) or Bq/cm
2
. If an alarm level is set in the cps mode,
it will not be available when in the Bq/cm
2
mode (and vice versa). An alarm is a continuous high
frequency tone whenever the measured reading exceeds the pre-set value. The alarm may be
deactivated by the operator. There is no mute (accept facility) for the alarm. Alarm activation is indicated
by a flashing loudspeaker icon.

4.6 Detector Probe
The T401 Contamination Monitor is equipped with a thin window Geiger Muller detector located in a special
probe attached to the head of the monitor. The detector has the capability to measure alpha, beta and
gamma radiation over a wide range of energies and its delicate, recessed front window is protected by an
open mesh steel grille during use. (Although the mesh provides protection from a rupture of the thin
window by large objects during use, the window remains delicate and vulnerable to puncture by thin
sharp objects and care should be exercised at all times when carrying out monitoring operations).
The detector probe normally rests within a special yoke attached to the monitor, with the face of the probe
orientated into and protected by the main body of the monitor. This orientation is recommended
during storage or transportation. The probe is connected to the monitor via a flexible cable which
is normally retained within the horseshoe-shaped skid attached to the monitor.
The probe is designed to be used in three possible ways during monitoring operations:-
Probe remains attached to the monitor yoke but rotated to suit monitoring requirements.
Probe and the yoke are decoupled from the body of the monitor for hand operation. The
flexible cable allows remote operation up to 1.5-metres from the body of the monitor.
Probe and yoke are removed from the body of the monitor and attached to the
extendable arm (purchased option). The orientation of the probe is adjustable relative to the
extension arm to provide maximum flexibility when monitoring. (Further information on these
monitoring options is provided in section 6 describing the detector probe).
4.7 Calibration
Current UK legislation requires that all operational radiation monitors are subject to annual inspection and
testing. This requirement includes for performance checks and where appropriate, recalibration of
the monitor.
The calibration due date will be displayed on a label attached to the monitor. This date will indicate
the 12-month anniversary of the current calibration. This can be added to appear on the monitor
screen during start up if requested on purchase or when calibrating the monitor; then when switching
on the contamination monitor, the next calibration check due date will register automatically on
the screen for approximately 2 seconds.
All Tracerco radiation monitors are checked and calibrated immediately prior to despatch to the
customer. Following this initial procedure (or the annual inspection and calibration check), Tracerco
operatives will re-set the next calibration check due date within the software of the monitor.
For further information on the calibration procedure refer to sections 7.3 and 9.

5 Measurement of Radiation Contamination
5.1 Procedure
Switching on the monitor will display all available segments for approximately 2 seconds (as shown below).
A check should be performed for any missing segments.
For the following 2 seconds, the next ‘Cal Due’ date will show using a MM-YY format. The monitor then
enters normal operation (cps mode).
5.2 Bargraph Display
This display provides a reading in the range 0cps –1000 cps. Maximum resolution is provided in the
range 0 –10cps, which is considered to be the most critical range for routine waste characterisation
purposes.
If the probe is exposed to activity levels which exceed the maximum count rate of 1000 cps, the
bargraph will remain at full scale deflection until the source of radiation is removed.
5.3 Digital Numeric Display
There is a 5 digit digital display. For radiation levels below 100cps or 100 Bq/cm
2
the monitor will
give a reading to 2 decimal places. The maximum indication is 4000 cps or its equivalent in Bq/cm
2
5.4 Peak Display
The meter is capable of numerically indicating the highest radiation level to which the probe has been exposed
since the instrument was switched on. Switching off will clear this reading.
Pressing the green“ PEAK ”button will show this reading. (During this period peak value continues to
be updated). A second press of the “PEAK” button during this period will return monitor to normal
function.
Pressing“ SELECT / RESET ”button whilst displaying the peak reading will reset the peak reading to
zero.
5.5 Mode / Select
The yellow“ MODE ”and green“ SELECT / RESET ”buttons are required when accessing various functions
associated with the monitor.

5.6 Nuclide Calibration Selection
In order to carry out a radiological assessment of the data obtained during contamination monitoring, it is
necessary to know the efficiency response of the monitor for the radionuclide under investigation
and to make the appropriate calculations.
The Tracerco T401 has been specially developed to provide a direct reading of the level of
contamination in Bq/cm
2
for a number of radionuclides which the operator can pre-select.
The efficiency calibration response functions of the monitor for various radionuclides are pre-
programmed into the instrument software. These functions are also checked and reset during
the annual inspection and calibration process.
In order to carry out a ‘statistically’ effective measurement of surface activity it is necessary to
accumulate counts over a reasonable timeframe and to make appropriate corrections for
‘background’ levels of radiation. The following procedures should be followed when carrying out a
radiological measurement.
5.7 Carry Out a “Background” Count
After switch on press the yellow“ MODE ”button to select the background function (allow 5 seconds for the
display function to normalise). The “ BGnd ”message will appear on the screen. Confirm this choice
by pressing the “ SELECT / RESET ”button.
The monitor will commence a background radiation count which will continue for a period which,
based on environmental levels, is sufficient to provide a statistically acceptable count. A typical
count duration is 60 seconds. The unit has been pre-programmed to accumulate and terminate this
count. During the count period, the display will show the real time integration of counts. After the
count has been automatically terminated, the display will show the mean value of the ‘Background’
count in counts per second. This value will be automatically stored in memory.
Press the“ SELECT / RESET ”button to accept this count and move to Bq/cm
2
monitoring. Alternatively
press the‘ MODE ’button to repeat a background count.
The background count will remain in memory after the monitor has been turned off. This value
will only be updated when the above procedure for carrying out a background count is
repeated.

5.8 Carry Out a “Nuclide Measurement”
Following selection of the background count the display moves to the Bq/cm
2
screen. Confirm this
choice by pressing the “ SELECT / RESET ”button, whereupon the message ‘ NUCL ’will appear on
the screen. The previously selected radionuclide will also appear at the base of the screen. Scroll back and
forth through the various nuclide options using the ‘ MODE ’and“ PEAK ”buttons to locate the one which
is required and confirm your choice by pressing the “ SELECT / RESET ”button. This operation will
also start the count integration.
(Note; there are 16 radionuclide options and one cps option, which, if chosen by pressing “ SELECT /
RESET ”, will revert the monitor to a cps display. Pressing the ‘ MODE ’button will continue the scrolling
operation, pressing the“ PEAK ”button will scroll in opposite direction). The unit will display the value
of“ Bq/cm
2
”in real time.
Pressing the “ MODE ”button whilst in “ Bq/cm
2
”will return the digital display and associated
functions to cps mode. (NB: The analogue display will always display “live” cps, irrespective of which
functions are being selected in the digital display).
Each nuclide has a different response factor ie the number of counts detected by the monitor per becquerel of
activity and the correct value of activity will only be displayed if the operator has selected the actual nuclide
which is being measure. A mis-selection will result in either a higher or a lower value than the result,
depending on the exact circumstances.

5.9 Nuclide Options
The Tracerco T401 monitor has been pre-calibrated to measure the list of nuclides given below.
These nuclides have been shown to be of general interest for a wide range of environments where
contamination monitoring might be required. In the event that the operator requires calibration against a range
of alternative isotopes, Tracerco will endeavour to provide the appropriate functionality (subject to the
availability of suitable calibration materials). These options are currently listed on the screen as Nuclide
1 to 9. The customer will be required to specify any additional nuclide calibrations at the time of
purchase (Subject to Tracerco having capability to source the appropriate radionuclides in a form
suitable for calibration). The identity of the radionuclides will remain on the screen as 1 to 9. It is
recommended that special calibration requirements be discussed with a representative of the Tracerco
monitor calibration and repair service.
Option 1
Americium-241
Option 2
Carbon-14
Option 3
Chlorine-36
Option 4
Lead-210 (d)
Option 5
Lead-210 (w)
Option 6
Radium-226 (d)
Option 7
Radium-226 (w)
Option 8
Strontium-90
Option 9
Cobalt-60
Option 10
Phosphorus-32
Option 11
Plutonium-239
Option 12
Uranium-238
Option 13
Caesium-137
Option 14
Nuclide 1
Option 15
Nuclide 2
Option 16
Nuclide 3
Option 17
Nuclide 4
Option 18
Nuclide 5
Option 19
Nuclide 6
Option 20
Nuclide 7
Option 21
Nuclide 8
Option 22
Nuclide 9
Wet and dry options (w) (d) provide alternative response coefficients to simulate the practical
conditions under which naturally occurring radioactivity is monitored in the environment (particularly within
the oil and gas industry). Calibration for Lead-210 assumes an equilibrium with daughter products
Bismuth-210 and Polonium-210.

5.10 Operational Ranges
Bargraph scale : 0 →1000cps.
Numeric scale : 0 →4000cps.
5.10.1 T401 Functional Diagram

5.11 Setting Alarm Trip Levels
The Tracerco T401 is equipped with an alarm function which can be set by the operator. The alarm is a
continuous high-pitched note and operates whenever the monitor reading exceeds a pre-set trip
level. The alarm trip level can be set in either counts / sec or Becquerels / cm
2
mode.
The incremental settings for the alarms are as follows:
Range
Increment
0 . 10
1.0
10 . 50
5.0
50 . 100
10.0
100 . 1000
100
1000 . 4000
500
Maximum alarm trip level is 4000 cps.
Range (Becquerels / cm
2
Increment
0 . 1.0
0.1
1.0 . 1.0
1.0
10 . 500
10
Maximum alarm trip level is 500 Bq / cm
2
5.11.1 Sounder Options
One normal press of the speaker button will turn on the sounder which will “click” in response to radiation.
In this (non-alarm) mode the speaker symbol will be on continuously.
A flashing speaker symbol indicates the alarm is set. For details, refer to page 12.
If the speaker symbol is showing an extended repeat sequence, it indicates that the alarm mode and
sounder are both activated.
If the speaker symbol is absent from the screen, it indicates that both audible response and alarm
setting is OFF.
It should be noted that on switching on, the monitor will retain the previous alarm trip level settings
and speaker status.

5.11.2 Setting the Alarm Trip Level
The following flow chart identifies the process for setting an alarm trip level in cps and Bq / cm
2
mode.
Symbol
Sounder
Alarm
Off
Off
Off
Continuous
On
Off
Short Flash
Off
On
Long Flash
On
On
It should be noted that the Bq / cm
2
alarm will only be operative when the monitor is being
used with the Bq / cm
2
mode selected on the digital scale. Since only a single value trip setting
can be entered in Bq / cm
2
, the operator must ensure that the selected value is consistent with
the type of radionuclide being monitored.

6 Detector Probe
The Tracerco T401 utilises a thin window Geiger Muller probe for the detection of alpha, beta and gamma
radiation over a wide range of energies. The probe has been designed to provide a high degree of
flexibility in the manner in which it can be deployed for contamination monitoring. The following are
examples of the key operational options.
6.1 Probe Retained in Monitor Yoke
During storage and transport, it is recommended that the probe is rotated to its non-operational
position so that the sensitive window is protected by the body of the radiation monitor. The probe is secured
in the yoke by a castellated ratchet mechanism with a positive retention pressure exerted by
special o-ring seals. The probe can be rotated to various orientations within the yoke. The monitor
can be operated with the probe and yoke remaining attached to the lower skid arrangement. The face
of the probe should be held some 2mm from the surface being measured to ensure optimal operation
and replicate the conditions under which nuclide calibrations have been carried out.
6.2 Remote Probe / Yoke Assembly
The operator may prefer to place the body of the monitor in a single location and use the probe to hand
monitor irregular items of equipment or areas difficult to access with a complete monitor. The probe
and attached yoke may be withdrawn from the body of the monitor by accessingthe retaining
lever which is located within the lower skid arrangement. The lever should be pushed sideways
and the yoke withdrawn from the retention assembly.
The probe is attached to the body of the monitor by a flexible coiled cable normally fully recessed
within the skid assembly. This cable will allow the probe to be operated up to a distance of 1.5-metres
from the body of the monitor. The cable has been specially selected to ensure that it returns to its
fully coiled resting state after use. It is recommended however, that care should be taken not to
persistently overstretch the cable during use.
The probe and yoke should always be replaced in the body of the monitor before trying to re-engage
the coiled cable in the skid arrangement.
6.3 Remote Probe with Telescopic Extension Kit
The base of the yoke has a threaded plug which allows it to be directly attached to an extendable arm, which
can be extended to approximately 1-metre.
The orientation of the probe within the yoke can be pre-set to the preferred arrangement for
monitoring. The extension arm is specifically designed to assist in monitoring floors, areas above head-
height and within straight pipes (the extension kit is an optional extra to the standard monitor

7 Maintenance and Calibration
The Tracerco T401 is a portable Contamination Monitor which incorporates many design features which are
based on Tracerco’s 40-years of global experience in the measurement of radiation in a wide
range of industrial and laboratory environments.
The monitor has been designed for reliable operation in relatively hostile environments and should
provide many years of effective service provided attention is paid to basic operational maintenance.
7.1 Battery Replacement
The condition of the battery is constantly monitored. Normal battery life is approximately 100-hours
for continuous or intermittent operation. With about 4 hours of battery life left, a “LO BATT” warning appears
on screen. When the battery power is too low for safe operation, the screen will blank.
The internal battery compartment is clearly identified but is located under the skid which holds the
probe and cable. This has to be removed (3 screws) to access the battery compartment. We would
recommend replacement battery of the type Duracell MX1 604 Alkaline Manganese or MN1604
Alkaline Manganese.
The battery cover can be removed by unscrewing the single retaining screw at the base. The gasket
seal is attached to the inner face of the cover. Care should be exercised not to damage this seal
or introduce contamination into the battery compartment.
7.2 General Maintenance
The liquid crystal display screen is sealed within the upper section of the case which provides a
robust, leak-tight fitting. The bargraph display has been specially selected for reliability in the field and the case
is constructed from a lightweight impact and chemical resistant polymer.
The only routine maintenance which is recommended is mild cleaning of the case and display to
prevent the build-up of grease and other potential contaminants.
Do not use solvents on the window.

7.3 Repair and Calibration
The Tracerco T401 instrument incorporates special software for checking and calibrating the response of the
monitor to incident radiation.
In order to comply with UK statutory regulations, the monitor must be inspected and tested on at
least an annual basis. It is recommended that such inspection and testing is carried out by Tracerco
or an approved organisation which has access to the appropriate testing equipment and diagnostic
software.
The Tracerco T401 monitor has been designed as a sealed unit, whereby all essential operating
parameters have been optimised and set at the time of manufacture and during test and calibration
procedures. These controls are not accessible to the customer and should not require any
adjustments during normal operation.
In addition to checking the physical condition of the monitor, Tracerco will check the response of the monitor
to the displayed radionuclides using special plaques whose radioactivity content per unit area of surface is
traceable to recognised national standards. Tracerco will consider modifying the list of calibration
nuclides, where the operator has a specific requirement and appropriate calibration materials can
be sourced.
Battery replacement will be a standard element of this annual inspection procedure.
7.3.1 Calibration Plaques
Where possible calibration data supplied for the Tracerco T401 Contamination Monitor has been measured
using large surface area reference plaques. These plaques comply with the requirements for
traceability to NIST specified in the ‘American National Standard Traceability of Radioactive
Sources to the N IST and Associated Instrument Quality Control (ANSI N42.22-1 995)’.
These plaques are constructed such that the radionuclides of interest are incorporated into the
surface of an anodised aluminium foil of 0.3mm thickness. The thickness of the activated layer
is approximately 6µm. In accordance with ISO8769, the calibration plaques are designated as Class
2 Reference Sources.

8 Technical Specification
Radiation detected
Alpha/Beta/Gamma
Automatic direct translation to Bq/ cm
2
for Cs-137, Am-241, C-14, Cl-36,
Pb-210 (wet and dry), Ra-226 (wet and dry), Sr-90, Co-60, P-32, Pu-239,
U-238
Detector
Single halogen thin window Geiger Muller tube
Over-range response
Bar graph display will read full scale. Digital numeric display shows 0UEr
(over) above 4000CPS
Variation with temperature
Less than 2%
Humidity range
0 to 95%
Ingress protection rating
Main case is sealed to IP65 sensor head sealed to IP34
Case material
Robust, chemical resistant polymers with ABS window
Weight
1 kilogram (approx.)
Display
Bar graph display (0-1000 CPS)
Digital numeric display in CPS or Bq/ cm
2
Battery
Standard 9V PP3 battery
Battery life
100 hours typically with background radiation
Low battery indication
On 4 hours battery life remaining
Variation with battery voltage
Less than 15% over operating temperature range
Standard compliance
EU directives: 2004/108/EC Electromagnetic Compatibility Directive