User Manual
Contents
1. 5 min 1 2 9 Continuous operation during ctore vtr oto 24 hours 1 2 10 Instability of readings during 8 hours of continuous operation relative to average value of readings Tor this period of time v cire c re o OO EE ES ERR tes VAR CREER Ra E RR YEAR 5 96 1 2 11 Power supply of the radiometer is provided from single phase AC mains with voltage 22072 V frequency 5071 Hz Limits of complementary measurement error due to deviation of voltage or frequency from their values specified for normal operating conditions cesses 5 L2 12 Power co s mpti n edi RETE e VD HERR EIER A Ca d not more than 40 VA 1 2 14 Operating conditions operating temperature range i c es eene autern ER nd minus 10 to 35 C maximum limit of relative humidity 2 0 75 at 30 C atmospheric pressure ease ere rer das o Se dur Re Cr QE SR 84 0 to 106 7 kPa content of the corrosive agents in the ambient air corresponds to the values in Table 1 1 FVKM 412121 001 RE 3 Table 1 1 Type of atmosphere Content of the corrosive agents Designation Designation Sulfur dioxide gas not more than 20 mg m day I Relatively clean not more than 0 025 mg m Chlorides not more than 0 3 mg m day 1 2 15 Limits of complementary measurement error due to deviation of temperature from2. aia 15 ET 15 PANS PORATION oh o uon date ru alus ces eua 15 s s lover E SNO tester 16 Appendix A Block diagram of the radiometer 17 Appendix B Wiring diagrams os eec sa be 18 Appendix C Connection layout esses 19 Appendix D Outline drawing od esa deine 20 Appendix E UMF PC interface 2 2 1 21 FVKM 412121 001 RE 2 This User Manual contains information on design principle of operation characteristics of the product and instructions essential for correct and safe use of this product intended use maintenance servicing storage and transportation as well as information regarding the utilization of the product 1 DESCRIPTION AND OPERATION OF THE PRODUCT 1 1 Product functionality The alpha beta radiometer UMF 2000 for low level activity measurements FVKM 412121 001 hereinafter radiometer is intended for measurement of total activity of alpha and beta emitting nuclides contained in counting samples of foodstuff soil and water collected on air filters and in sorbents as well as for measuring the activity of nuclides in the samples obtained by selective radiochemical extraction total activity of alpha emitting nuclides in thick and thin counting samples of environmental samples The radiometer is used in
3. and TIME In the mode the indicator displays alpha and beta counts while in the B TIME mode it is beta counts and elapsed time The indication mode does not affect the operation of the radiometer 1 3 6 3 In the case of an overflow in one of the channels counting stops and the central segments are lit at the indicator corresponding to the overflowed channel At that it is possible to view the content of other channels Stopping of counting is accompanied by an audible signal To turn the signal off press the STOP button or start a new measurement 1 4 Marking and sealing 1 4 1 The following information is presented on the radiometer trademark and name of the manufacturer supplier reference designation of the radiometer works number of a radiometer according to the manufacturer s system of numeration degree of ingress protection against solid items and water provided by casings voltage power consumption or current power supply frequency 1 4 2 Location and method of marking of the radiometer correspond to the design documentation 1 4 3 The radiometer is sealed in accordance with the design documentation 1 5 Packing 1 5 1 The radiometer s package complies with the design documentation and provides protection against ingress of atmospheric precipitations and aerosols splashes of water dust sand solar ultra violet radiation and limits the ingress of water vapour and gases 2 INT
4. LEMO connector built into the detector s mandrel The drum has four fixed positions for measurement which can be identified by a light blocking the drum as it rotates 1 3 2 2 The counting sample holder has four seats to accommodate plates with counting samples with the outer diameter of 45 mm The drum has four fixed positions for measurement which can be identified by a slight blocking of the drum as it revolves To accommodate a counting sample in a fixed position relative to the detector it is necessary to rotate the drum to the next position The radiometer with a detector area 1000 mm comes with a drawer type counting sample holder Before measurement one need to pull the holder place a plate with counting sample and then push the holder in place to the extreme position WARNING The space is provided in the radiometer for measurement of samples on thick plates The same place is used for calibration of the radiometer with the use of filters The place for thick plates is 1 mm deeper than the standard locations for counting samples and marked The radiometer with a detector area 1000 mm the place for a check source is located on the bottom surface of the insert for counting samples To install the check source turn the insert upside down 1 3 3 The controlling part includes a power supply module and module of conditioners which serves to separate the pulses from alpha and beta particles and has an anticoincidence circuit high voltage
5. 3000 s at least 5 times background measurements shall be carried out with empty plate in the counting position of the detecting module 2 calculate the average background count rate in channels Dog by the formula N ibgr Nber Mr 4 9 liner M gt i l where is the number of counts obtained in i th background measurement t4 is the i th measurement interval k is the number of background measurements 3 perform measurement of count rate with Cs source and thin of determination of activity measurement error Pu source with the purpose 4 determine the average count rate from counting sample n including background k n 4 10 5 1 1 where N number of counts obtained in i th measurement t i th measurement interval 5 determine the average count rate from counting sample n excluding background T sample n 2x 4 1 1 6 perform measurement of count rate with combined check source complete with radiometer 4 3 4 4 Processing of measurement results Calculate the uncertainty of determining the activity of radionuclides in counting samples With this purpose determine the measured activity values A of working standards Cs and Pu by the formula FVKM 412121 001 RE 14 Mes Nsample 4 12 5 where amp is the radiometer s sensitivity for a given source radionuclide determined at the phase of putting radiometer into operation and stated
6. controlling part active cosmic ray shielding electronic parts two channel counting device with timer Block diagram of the radiometer is given in Appendix A The radiometer s front panel accommodates buttons START and STOP of the counting device indicators counting mode switch accounts and two LEDs one indicates that the power supply is on and the other one that the counting process is under way The radiometer s rear panel accommodates protective terminal strip power switch connectors EXIT and RS 232 Electric circuit wiring diagram overall and fitting dimensions of the radiometer are presented in the Appendices B C and D 1 3 2 The detecting device contains Semiconductor detector of high resistivity Al doped silicon the size of 20x20 mm or 32x32 mm in a mandrel of chromium plated brass counting sample holder with a device for advancing them to a fixed position near the detector FVKM 412121 001 RE 4 1 3 2 1 The semiconductor detector converts the energy of alpha and beta particles into electrical pulses by means of charge sensitive preamplifier The detector detects beta particles in the range of energies starting from 50 keV It works as a transmission detector it means that there is no information about the passed particle energy When registering alpha particles the detector is capable of providing spectrometric signal Connection between detector and preamplifier is provided using the
7. jo O NU Pan eeno e peau z qun ON me e g 2105 A052 2105 1057 AZ UNO GND dase 1721 7007 72 panog 29140047941 ZV pun Janjan zv ES FON 413 5 LS LX 4 207 50 RE gt ex g zee 78 i 1 andino Jwz dX 9X LODZLSLUE WIA jou 200 22521 WHA 4209 jew LV INV3DVIG 6101281190 g xipuoddy FVKM 412121 001 RE 18 Appendix C Obligatory CONNECTION LAYOUT Al 95 232 X3L2 Output 4 lt fon lasing 7 Cable f Cable with a molded plug ShVVP VP 2 6 5 25 m 2 Cable 2 data cable DB 9F DB 9F length up to 10 m X50 X51 fable socket Circuit Circuit FVKM 412121 001 RE 19 Jis awg 9 To Y ard 992 ANI TLOO 6101281190 xipuoddy FVKM 412121 001RE 20 Appendix E obligatory INTERFACE E 1 When the radiometer is turned on with preset non zero measurement interval it switches to manual mode In this case radiometer execute all commands which result in a transfer to a PC of certain parameters commands that change current sta
8. lt Scientific Production Company Doza ALPHA BETA RADIOMETER 2000 FOR LOW LEVEL ACTIVITY MEASUREMENTS User manual FVKM 412121 001 RE ON tA Content Description and operation of the product 3 1 1 Prodact dtihetlonalit yo 52 e cue ies 3 1 2 Technical characteristics ka tendere da Qoa dece ds e ettet a 3 1 3 Design and operation c dvds 4 1 4 Marking and sedie ais des d reve coeds eoru ote ted res 6 kil Soros daa dito 6 Intended Use ose eis e sas GR EGRE CUR ERR a 6 2 1 Operational limitations ins 6 2 2 Preparation of the product for use 6 2 set a product si cag acd eren tese ea 7 Niaintendtop Oeste esta coke 9 3 1 General Notes retis ee e a eR E rileva an 9 3 Safety prec quos cerca vo erede bet oh ates E 9 3 3 Maintenance routines oic e heaters ere Rea IR eos 9 Calibration routine sso esed e Rae EHE 9 4 1 General requirements 5 ERO CO at 9 4 2 Calibration procedure during putting into operation 9 4 3 Calibration procedure during operation 13 Routine degustar tan eee rada bh hoo
9. module for HV supply to active shielding and protection against power line disturbances The power supply module is used to convert the AC voltage 220 V to 12 V 12 V and 5 V DC for electronic devices In addition the power supply module generates bias voltage for the detector 1 3 4 The active cosmic ray shielding includes gas discharge counter located under the counting samples holder The active shielding is used to reduce the contribution of high energy cosmic rays to the detector s background When a charged particle hits the detector a signal in the form of a voltage pulse from the detector is delayed and transmitted to the counting circuit only if within the waiting time a pulse is not received from the active shielding system or from the system of protection against power line disturbances Otherwise the pulse from the detector is ignored 1 3 5 The electronic part is designed as separate blocks preamplifier conditioners power supply counting device controller board with timer and two indicator boards 1 3 5 1 The preamplifier is designed by the classical resistive circuit due to low detector s inverse currents allows having a noise at a level of 5 15 keV Pre amplified signal is transferred to the input of the main amplifier which uses a high speed operational amplifier The main amplifier provides output signal amplitude for beta particles at the level of 20 mV to 1 V The amplified signal is fed to the input of the select
10. o is the total measurement time of the background 2 3 5 The calculation according 2 3 3 and 2 3 4 shall be performed for each channel 2 3 6 Calculate the activity A for the measured counting sample by the formula Nsample As 2 5 where sis the sensitivity of the radiometer for measured type of radiation stated in the calibration certificate of the radiometer Calculate the relative error of measured activity 5A in percentage terms according to the formula An sample 8A 1 1 2 6 Nsample where is the relative error of sensitivity stated in the calibration certificate 2 3 7 Record the activity A Bq of the measured counting sample taking into account the errors in a form Ada E 2 7 100 2 4 When working with radiometer it is recommended to use Methods for measuring the total alpha and beta activity of water samples fresh natural waters for household use after concentration using alpha beta radiometer UMF 2000 and guidelines Gross activity of alpha and beta emitting radionuclides in natural fresh and mineral waters Sample preparation and performing measurement 2 5 Optional spectrometric ADC signal cable software Spdec and radiochemical methods of selective electrochemical deposition allows using the radiometer for activity measurements of corresponding alpha and beta emitting radionuclides FVKM 412121 001 RE 8 3 MAINTENANCE 3 1 General notes Maintenance is performed
11. with the purpose of ensuring reliable long term operation of radiometer The following types and timing of maintenance work are recommended Misualmnspee Hof every month s External cleaning esae site rendo every month Resting OF malt eem debet tee Dre ns every year 3 2 Safety precautions 3 2 1 Before beginning to work with radiometer familiarize yourself with this User Manual 3 2 2 During all operations with detectors follow occupational and radiation safety requirements of current safety instructions in the company enterprise 3 2 3 The radiometer should be reliably grounded through the ground terminal on the rear panel during operation 3 2 4 The voltage 400 V is produced in the high voltage module for supply of the active shielding system do not open the radiometer case earlier than 10 minutes after it is turned off The power supply voltage 220 V is present in the radiometer therefore it is prohibited to connect it to the electrical network when the cover is removed 3 3 Maintenance routine Maintenance is divided into routine and periodic 3 3 1 Routine maintenance 3 3 1 1 Routine maintenance is carried out during regular operation it includes inspections of radiometer for timely detection and elimination of factors which can compromise their operability and safety If any
12. ENDED USE 2 1 Operational limitations 2 1 1 Radiometer retains operability under conditions stated in 1 2 2 1 2 Using mobile phones is prohibits near the operating radiometer WARNING DO NOT USE RADIOMETER FOR PERFORMING MEASUREMENTS OF SAMPLES WITH HIGH CONTENT OF ACIDS OR ALKALI TO PREVENT DAMAGE TO THE WORKING SURFACE OF DETECTOR 2 2 Preparation of the product for use 2 2 1 Before using the radiometer check that the power cord is connected correctly and not damaged check grounding After that connect the power cord to the wall outlet and turn the power switch located on the rear panel to the POWER ON position At that time the red LED must light up located next to the marking POWER on the front panel FVKM 412121 001 RE 6 2 2 2 Immediately after turning the radiometer on it switches to the test mode which facilitates performance testing At that time the top indicator displays internal serial number of the radiometer which is used to control it via RS 232 and the lower indicator displays elapsed time Pressing and holding the mode selection button allows to displaying on the top indicator of the time interval set by time controller By changing the settings of digital switches while holding the button the value of time set by these switches can be compared against the value which will be used during real measurements To activate the operating mode press the START button 2 2 3 The radiometer is capable to oper
13. ate under external control using RS 232 interface the RS 232 connector is located on the rear panel To switch to the external control mode set the digital switches of the time controller to 0000 before switching the radiometer on After that the radiometer will not respond to pressing buttons on the front panel Commands for controlling the radiometer are listed in the Appendix D 2 2 4 Using mode selection button select or TIME mode 2 2 5 Warm up the radiometer during 30 minutes 2 2 6 Load an empty plate previously wiped with a tissue moistened with alcohol to the counting position and perform background measurement for at least 1000 seconds Make sure that the background value is within the limits specified in the certificate of calibration If you notice increase in the background identify and fix the problem 2 2 7 Place the check source complete with radiometer to the counting samples holder and perform measurement during 300 seconds The obtained value of count rate should be within the limits specified in the certificate of calibration WARNING THE CHECK SOURCE SHALL BE PLACED INTO THE DEEPENING MARKED BY RED OR WHITE DOT OR INTO THE UPTURNED INSERT FOR RADIOMETERS WITH DETECTOR WITH AREA 1000 MM 2 2 7 Proceed to routine measurements 2 3 Use of a product 2 3 Operations needed to determine the activity of a counting sample include measurements of count rate with an empty plate background and with a
14. counting sample on a plate The measurements are carried out with drum in a fixed position 2 3 2 During measurements you should use the value of background which is obtained as the average of 8 10 measurements at that each of the background measurements should record at least 10 counts Later on the purpose of background measurements should consist in demonstration of compliance of the current background value with the average one taking into account the statistical spread The statistical error of the background measurement 6 is given by 58 1 96 2 1 ber gt where is the number of background counts 1 96 is the Student s coefficient at a confidence level 95 2 3 3 Perform several measurements of a counting sample The measurement result is expressed as counts registered by the radiometer in both channels during the time t FVKM 412121 001 RE 7 Determine the average count rate from counting sample including the background by the formula k c n 2 2 2t i l where N is the number of counts obtained in i th measurement t is the i th measurement interval 2 3 4 Determine the average count rate from counting sample n excluding background Nsample N 2 3 where nig is the average count rate Calculate the absolute error in the count rate Anse cps using the formula AN sample 1 96 2 4 lon oer where t is the total measurement time of the sample meas t
15. dity aus eres ER from 30 to 80 Jabmosphleric pressilte i e oss te ptc o ea A Mui Ee pelea 86 0 to 106 7 kPa natural radiation background 2 2 not more than 0 2 uSv h FVKM 412121 001 RE 13 In the process of calibration the possiblility should be excluded of the external radiation background increasing due to extraneous radioactive sources 4 3 4 Performing calibration 4 3 4 1 External examination Items to be checked during external examination Proper completeness Presence of seals Absence of defects which could affect the radiometer s operation Availability of operational documentation 4 3 4 2 Testing Testing of radiometer includes turning it on determination of operability of LEDs and digital indicators testing START and STOP buttons and operation of timer To test the timer select B TIME mode set measurement interval equal to 1 s and press START Watch indication of time in seconds on the lower digital indicator Note that the measurement stops after 1 second Repeat the last step with the measurement interval settings 10 100 and 1000 seconds 4 3 4 3 Determination of the basic relative error of activity measurements 1 after warm up and reaching operation condition of the radiometer perform background measurements simultaneously in the alpha and beta channels with measurement interval
16. e PC control mode Note Subsequent manipulations with digital switches will not switch the radiometer to manual mode In this mode START and STOP button are blocked The radiometer executes all commands from the PC In test mode pressing the START button resets the timer readings displayed on the lower indicator When the radiometer is restarted to the next measuring cycle the acquired data will not reset E 3 Data via serial port are transferred at the speed of 19200 baud using the RS 232 interface The parcel is only accepted if at least 10 ms have passed since the receipt of the last byte any byte transferred from the central PC to any radiometer the first byte in the parcel is equal to the radiometer number 1 255 or is an interrogation byte 0 The radiometer reads a specified number of bytes defined by number of commands transmitted in the second byte of the parcel If transmission error is detected next byte has expired or checksum does not match the radiometer generates a message lt OBBh gt Note byte is considered expired if it is delayed relative to the previous one for more than 10 ms After receiving and analyzing a parcel the radiometer executes the command set if enabled and generates a confirmation message The functions realized in previous models of radiometer which are not mentioned in this text remained unchanged FVKM 412121 001 RE 2 Table E 1 The structure of the c
17. erval k is the number of background measurements 3 measure the count rate for the working standards Cs and Sr y measurement interval shall be large enough to ensure registration of at least 1000 counts in two channels simultaneously and at least five times FVKM 412121 001 RE 11 4 calculate the average count rate n for each sample by the formula Mr 2 4 2 5 Mr where number of counts obtained in i th measurement t i th measurement interval k number of measurements of the sample record the obtained results in the calibration report of any from 5 calculate the average count rate n excluding background and its statistical uncertainty S ER in absolute values for each nuclide and sample mass respectively by the formulas Nea N Nog 4 3 n n s na p 4 4 toe where tonic is the total measurement time of the sample s 15 the total measurement time of background s 6 calculate the sensitivity of the radiometer for Cs and by the formula 4 5 for each value of the weight of the source weighted portion source weights for Cs and are stated in certificate of calibration 4 5 where 4 is the activity of the working standard calculated by the formula 0 693 t 1 Pis 4 6 where A is the activity of the working sta
18. gt lt 07h gt lt PAGE gt lt ADR gt E ua at address ADR lt KC gt lt Ne gt lt 07h gt lt DAT gt lt bC gt lt KC gt 08h lt No gt lt 08h gt lt H gt lt LO gt lt KC gt lt No gt lt 08h gt lt BC gt lt KC gt Report bank 256 bytes 5 lt Ne gt lt 09h gt lt DAT o gt lt DAT gt 09h No PAGE lt gt lt gt lt gt Write a byte in EEPROM into memory lt No gt lt 0Fh gt lt PAGE gt lt ADR gt PAR bank PAGE at address ADR lt DAT gt lt KC gt D OBh lt No gt lt 0Bh gt lt KC gt No gt lt 0Bh gt lt BC gt lt KC gt lt No gt lt 0Ch gt lt KC gt No gt lt 0Ch gt lt BC gt lt KC gt ODh Stop counting Me 0Dh KC No gt lt 0Dh gt lt bBC gt lt KC gt Start counting Ne 0Eh KC No gt lt 0Eh gt lt BC gt lt KC gt GF RESERVE FVKM 412121 001 RE 25
19. in the certificate of calibration Determine the error of radionuclide activity measurement in percentage terms by the formula 2 8A 1 1 AAS oo Ae 4 13 0 where Ay is the activity of the working standard stated in the certificate of calibration Bq is the uncertainty of sensitivity for particular radionuclide The obtained result should not exceed the value stated in 1 2 4 5 ROUTINE REPAIRS 5 1 Modules of the radiometer are not repairable and in the case of a failure should be replaced at the factory of manufacturer 6 STORAGE 6 1 Prior to putting into operation radiometer shall be stored in a heated warehouse with natural ventilation in manufacturer s package at ambient temperatures from 5 to 40 C and relative humidity up to 80 at 25 C unpacked at ambient temperatures from 10 to 35 C and relative humidity up to 80 at 25 C 6 2 The storage location should be free of dust chemical vapours aggressive gases and other substances that may cause corrosion The storage location shall exclude exposure of radiometers to the direct rays of sunlight 7 TRANSPORTATION 7 1 Radiometer in the original manufacturer s package can be transported by all means of transport at any distance transportation by railway shall be carried out in clean boxcars when transported by open motor transport boxes shall be covered by the water proof material when transported by air the bo
20. ion circuit in the electronic part made with integrated comparators Comparator thresholds are set so that the first comparator is triggered by both alpha and beta particles pulses and the second one is triggered only by alpha particles pulses The signals from comparators are fed to the anticoincidence circuit which permits counting of beta particles only beta channel For the alpha particles counting only the signal ofthe second comparator is taken into account The electronic part also accommodates the anticoincidence circuit for systems of active shielding and protection against power line disturbances 1 3 5 2 The electronic part also includes a pulse power supply module and a high voltage module FVKM 412121 001 RE 5 1 3 6 The two channel counting device with timer consists of three counting paths with four digit indicators and an electronic timer The duration of measurement is determined by time selector four digital switches Pushbutton switches located on the front panel allow to start the measurement with simultaneous reset of the previous result and to stop the measurement at any time 1 3 6 1 The counting scheme is built with the use of a microprocessor information is displayed on seven segment LEDs and has two channels 1 3 6 2 Pulses corresponding to alpha particles are counted in the first channel the second channel is used for counting of pulses from the beta particles The indication mode can be changed using buttons a
21. ion of operability of LEDs and digital indicators testing START and STOP buttons and operation of timer To test the timer select B TIME mode set measurement interval equal to 1 s and press START Watch indication of time in seconds on the lower digital indicator Note that the measurement stops after 1 second Repeat the last step with the measurement interval settings 10 100 and 1000 seconds 4 2 4 3 Determination of the radiometer s sensitivity 1 using granulated sources and K prepare weighted portions on plates for measuring in accordance with the Table 4 2 Table 4 2 Samples weighted portions for calibration Weighted portions Weighted portions K radiometer with detector 450 mm 20 mg 100 mg 50 mg 300 mg 100 mg 200 mg radiometer with detector 1000 mm 100 mg 100 mg 200 mg 200 mg 400 mg 400 mg 600 mg 2 after warm up and reaching operation condition of the radiometer perform background measurements simultaneously in the alpha and beta channels with measurement interval 3000 s at least 5 times background measurements shall be carried out with empty plate in the counting position of the detecting module Calculate the average background count rate in channels nig by the formula Dog 4 1 2 tie where is the number of counts obtained in i th background measurement t4 is the i th measurement int
22. laboratories for monitoring of water bodies 1 2 Technical characteristics 1 2 1 Energy range of measured alpha radiation 3500 to 8000 keV 1 2 2 Energy range of measured beta 50 to 3500 keV 1 2 3 Activity measurement range 5 alpha radiation 5 0 01 to 10 IDS ta circus EDT TIL SES 0 1 to 3 10 1 2 4 Limits of the permissible basic relative measurement error 15 1 2 5 Radiometer maintains operability under the influence of the external background gamma radiation with energy of 662 keV and absorbed dose rate 0 50 uGy h under these conditions the limit of complementary measurement error 18 15 1 2 6 Background count rate detectors with area 450 and 1000 mm in the alpha measurement channel iss oon ee teer e etes not more than 0 001 cps detectors with area 450 mm in the beta measurement channel 0 2 not more than 0 03 cps detectors with area 1000 mm in the beta measurement 24 not more than 0 07 cps 1 2 7 Contribution of alpha channel into count rate of beta channel for thin alpha Source iocos ur a Re IR e RR IRE ETE not more than 0 8 96 1 2 8 Warm up time under stable external conditions not more than
23. more than 15 keV activity 1 50 Bg uncertainty not more than 5 95 Check source OISN 238 U 230 with activity 20 200 complete with radiometer Stopwatch tweezers Note It is allowed to use other tools and equipment with similar characteristics ensuring determination of metrological characteristics of radiometer with required precision 4 2 2 Safety precautions During calibration follow safety requirements described in section 3 2 and in documentation accompanying calibration tools and equipment 4 2 3 Conditions for calibration and preparation for calibration The following normal operating conditions shall be met during calibration E uoc TTE 20 5 C Bumidity SR eee pret pae from 30 to 80 96 atmospheric pressure RR NUES qa CX 86 0 to 106 7 kPa natural radiation background not more than 0 2 uSv h In the process of calibration the possiblility should be excluded of the external radiation background increasing due to extraneous radioactive sources FVKM 412121 001 RE 10 4 2 4 Performing calibration 4 2 4 1 External examination Items to be checked during external examination Proper completeness Absence of defects which could affect the radiometer s operation Availability of operational documentation 4 2 4 2 Testing Testing of radiometer includes turning it on determinat
24. ndard from the certificate of calibration t is the period of time elapsed since the time of source calibration years is the half life of the radionuclide years is the working standard uncertainty 7 calculate the uncertainty of sensitivity in percentage terms by the formula 2 AR E 100 A 4 7 cal where 1 96 is the Student s coefficient at a confidence level 95 96 84 is the uncertainty of the working standard Recorded the values of and in the certificate of calibration 4 2 4 4 Determination of the basic relative error of activity measurements 1 perform activity measurement with any Cs source and with thin source in accordance with the procedure set out in 2 3 FVKM 412121 001 RE 12 2 determine the error of radionuclide activity measurement percentage terms by the formula 2 A A 8A S 4 8 As where 15 the value of activity determined in accordance with the method set out in 2 3 isthe activity of the working standard from the certificate of calibration is the uncertainty of sensitivity for particular radionuclide The obtained results should be in the range stated in 1 2 4 3 measure the value of the count rate from the check source and record it in the certificate of calibration 4 3 Calibration procedure during operation This procedure applies to radiometers in operation and establishes meth
25. normal value to the limits of range of operating 2 5 1 2 16 During operation the radiometer shall not be subjected to vibration shocks and other mechanical impacts 1 2 17 Degree of protection against ingress of solid items and water provided by radiometer s casings IP23 1 2 18 Radiometer is stable against electromagnetic interference of 2 grade according to the IEC 1000 4 8 93 IEC 61000 4 2 95 IEC 61000 4 3 2006 IEC 61000 4 4 2004 IEC 61000 4 5 95 IEC 61000 4 6 96 IEC 61000 4 11 2004 1 2 19 Radiometer complies with the emission standards stated by the CISPR 16 1 93 CISPR 16 2 96 for equipment of class A 1 2 20 By its protection against electric shock radiometer complies with the IEC 61010 1 2001 1 2 21 Radiometer is a fire safe product with fire probability of not more than 10 year 1 2 22 Radiometer withstands the exposure to 5 citric acid solution in the rectified ethyl alcohol C2HsOH density 96 1 2323 imensiOns pe No HE xe cela 321x286x190 mm 12 24 Weight ses sese not more than 21 6 kg 1 2 25 Mean time to failure e icr Sioa d not less than 10000 hours 12 2 6 Mean life time iios ot a t ost e eua ace AE Vedan not less than 5 years 1 3 Design and operation 1 3 1 The radiometer is assembled in a single case and consists of detecting device
26. ods and means of calibration 4 3 1 Calibration operation and equipment Operations performed during calibration and necessary equipment are listed in the Table 4 3 Table 4 3 Calibration operations and calibration equipment Operation Section Cahpranen equipment and its technical characteristics 1 External 4 3 4 1 Visual examination 2 Testing 4 3 4 2 3 Determination of 4 3 4 3 Working standards basic relative error special purpose source Cs with thickness 0 02 0 06 g cm of activity activity 50 200 Bq uncertainty not more than 9 95 measurement thin source on the plate with self absorption not more than 15 keV activity 1 50 uncertainty not more than 5 Check source OISN 238 5U 230 with activity 20 200 complete with radiometer Stopwatch tweezers 4 Processing of 4 3 4 4 measurement results Note It is allowed to use other tools and equipment with similar characteristics ensuring determination of metrological characteristics of radiometer with required precision 4 3 2 Safety precautions During calibration follow safety requirements described in section 3 2 and in documentation accompanying calibration tools and equipment 4 3 3 Conditions for calibration and preparation for calibration The following normal operating conditions shall be met during calibration LIU ETIN TE 20 5 C delative au h mi
27. ometer s surfaces including surfaces accessible during repair can be reduced below allowable limits In case the radioactive contamination exceeds allowable limits requirements set forth for the radioactive wastes become applicable to the detectors 8 3 Radiometer accepted for operation after decontamination shall be repaired or replaced in case of failure Radiometer which is not suitable for operation with radioactive contamination levels below permissible limits should be dismantled to preclude its further use and transferred to a special site for disposal of industrial wastes 8 4 Radiometer with expired lifetime accepted for use after decontamination shall undergo technical inspection If the technical condition of a radiometer is satisfactory an extended operation term of the product shall be determined FVKM 412121 001RE 16 Appendix A Obligatory BLOCK DIAGRAM OF THE RADIOMETER where 1 counting sample holder 2 counting sample 3 detection device 4 active shield 5 preamplifiers 6 discriminators 7 anticoincidence circuit 8 timer 9 power supply unit 10 high voltage unit 11 indicators FVKM 412121 001 RE 17 1 TA 1 Nz ujag i X 28 i 0 570 40433430 28 WW DOC 0 sJo0 3npuo Jo UOISLAA UO Spuadar Z ou Si 430jU0 1 Ajddas Jaunduma tf JojpJodum3
28. ontrol byte E Bit is equal to zero Bit is equal to 1 0 radiometer is idle radiometer is working 1 radiometer is in test mode radiometer is in working mode 2 overflow of channel 0 3 overflow of channel 1 4 data from channel 0 are already read 5 data from channel 1 are already read 6 radiometer is manually controlled radiometer is controlled from PC 7 EEPROM read error WARNING If during reading of the next byte from EEPROM an error occurs then the total duration of attempts per byte will be approximately 100 ms as a result the period between transfer of bytes of a parcel can vary and fall in the ranges from 0 1 ms to 100 ms The total response time can reach 2 5 seconds FVKM 412121 001RE 22 Table E 2 List of commands executed by the radiometer number RESERVE 25 22 4222 222 gt lt 01 gt lt gt gt lt 01 gt lt gt lt gt 02h No gt lt 02h gt lt KC gt No gt lt 02h gt lt HI gt lt LO lt BC gt lt KC gt No gt lt 03h gt lt KC gt No gt lt 03h gt lt HI gt lt LO gt lt BC gt lt KC gt 04h No gt lt 04h gt lt KC gt No gt lt 04h gt lt HIp gt lt LOp gt lt BC gt lt KC gt lt No gt lt 0Sh gt lt KC gt No gt lt 0Sh gt lt HI gt lt LO gt lt BC gt lt KC gt 06h Report ALL data lt Ne gt lt 06h gt lt KC gt SEE SHE Ox HIo gt lt LOo gt lt HI gt lt LO gt lt bC gt lt KC gt Report byte from memory bank PAGE lt No
29. te of the radiometer are blocked a command is received processed but the prescribed actions are not performed the returned status byte contains information about the state of the radiometer at the moment when operation is complete START and STOP button are operable inthe test mode immediately after the radiometer is turned on the upper indicator displays the serial number of current turning on in the N xxx format When buttons or B TIME pressed and hold instead of radiometer s number a value read from the digital switches time setting is displayed The lower indicator displays seconds since the turning on of the radiometer The STOP button in this mode generates an audible signal The START button starts measurement E 2 After normal completion of acquisition elapsed time equals to the preset time counting measurement stops the LED MEASUREMENT goes out and an intermittent beep is heard which can be switched off by the STOP button If counting is stopped as a result of pressing the STOP button or manipulations with timer when elapsed time exceeds the newly set value than the lower indicator alternately shows timer value and counting channel value Next measurement cycle can be started by pressing the START button measurement data are automatically reset simultaneously When the radiometer is turned on with zero time set by digital switches it is in th
30. uring calibration and necessary equipment are listed in the Table 4 1 Table 4 1 Calibration operations and calibration equipment Calibration equipment mech and its technical characteristics 1 External 4 2 4 1 Visual examination 2 Testing 4 2 4 2 3 Determination of 4 2 4 3 Working standards sensitivity of the special purpose sources Cs with thickness 0 02 0 06 g cm radiometer at least three sources with different thickness activity 50 200 Bq uncertainty not more than 9 95 special purpose sources Sr Y with thickness 0 02 0 06 g cm at least three sources with different thickness activity 50 200 Bq uncertainty not more than 9 95 thin source on the plate with self absorption not more than 15 keV activity 1 50 uncertainty not more than 5 Working standard grade 2 based on granulated source 239Pu specific activity 10 50 Bq g uncertainty not more than 10 95 Working standard grade 2 based on granulated source 40K specific activity 10 50 Bq g uncertainty not more than 10 Check source OISN 238 238U 234U with activity 20 200 Bq complete with radiometer Stopwatch tweezers 4 Determination of 4 2 44 Working standards basic relative error special purpose source Cs with thickness 0 02 0 06 g cm of activity activity 50 200 Bq uncertainty not more than 9 95 measurement thin source on the plate with self absorption not
31. warping or damages are found immediately eliminate them to avoid the failure of the radiometer 3 3 2 Periodic maintenance Periodic maintenance consists of calibration and decontamination of the radiometer 3 3 3 Deactivation of the radiometer is carried out in accordance with current decontamination regulations of enterprise facility as well as after increasing of the radiometer s background above the permissible level The drum drawer for sample plates shall be decontaminated and if necessary the external surfaces of the radiometer decontamination solutions shall be used in accordance with 1 2 21 4 CALIBRATION ROUTINE 4 1 General requirements 4 1 1 Calibration of radiometer shall be carried out in accordance with the requirements of IEC 61453 2007 4 2 Calibration procedure for putting into operation The calibration procedure for putting the radiometer into operation and relevant metrological characteristics shall be based on the user s specific measurement tasks The following parameters are to be determined and recorded in the calibration certificate during primary calibration of each radiometer detection efficiency of alpha and beta particles depending on counting samples weight reference values of the count rate from check sources 8 and for a fixed geometry of measurements the values of background for alpha and beta channels FVKM 412121 001 RE 9 4 2 1 Calibration operation and equipment Operations performed d
32. xes with radiometers shall be placed in air tight heated compartment when transported by water and sea transport the boxes with radiometers shall be placed in the hold 7 2 Arrangement and fastening of the boxes on transport means shall provide their steady position en route absence of displacement and striking each other 7 3 The requirements of the inscriptions on the transport packing shall be observed during loading and unloading During loading and unloading radiometer should not be exposed to precipitation FVKM 412121 001RE 15 7 4 Transportation conditions are as follows T temperature asian uds tois from minus 30 to 50 C provided gradual temperature stabilization is ensured during unloading at temperatures from 10 to 35 C and subsequent storage under the normal conditions during 24 hours gags tee up to 95 at 35 impact of shaking with an acceleration 30 m s at a frequency of 10 120 shocks min 8 UTILIZATION 8 1 On full expiry of the service life of radiometer or its parts and also prior to its dispatching for repair or calibration it shall be inspected for possible radioactive contamination of its surfaces Criteria for decision making on decontamination and further use shall comply with obligatory requirements of national standards 8 2 Decontamination shall be attempted in cases when the contamination of radi
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