User Manual
Contents
1. DIAGRAM OF INSTALLING THE CLIPS ON THE IONIZATION CHAMBER Chamber Clips DBKM 412113 017P3 162. notice of nonoperability of the dosimeter is issued or the appropriate record is made in the technical documentation and use of the dosimeter is not admitted 5 ROUTINE REPAIR 5 1 Routine repair of the dosimeter consists in restoring the damaged cables and connectors The dosimeter elements are non repairable and in case of failure should be replaced or repaired at the manufacturer 6 STORAGE 6 1 The dosimeter prior to putting into operation should be kept in a heated and ventilated storehouse inthe manufacturer s packaging under conditions 1 L according to GOST 15150 69 at the ambient temperature of 5 to 40 C and relative humidity up to 80 at 25 C without packaging 10 to 35 C and relative humidity up to 80 at 25 C under DBKM 412113 017P3 14 conditions of atmosphere type I according to GOST 15150 69 6 2 Storage period without re conservation is 3 years 6 3 Storage premises should be free from dust acid and alkaline vapors corrosive gases and other harmful corrosion causing impurities Storage place should exclude entry of the direct sunlight on a dosimeter 7 TRANSPORTATION 7 1 The dosimeter in the manufacturer s packaging may be transported by all means of transport at any distance under observation of the following conditions transportation by rail freightage should be carried out in covered clean boxcars upon transportation by open motor transport the boxes with dosimeters should be cov
3. and material of the optional filter in this manual an optional filter of 2 mm Al in thickness is assumed dose area product over the period of X ray procedure performance cGy cm examination area lungs skull etc projection anterior posterior posterior anterior lateral radiation field size height and width at the image detector cm focal distance distance from the X ray tube focus to the image detector cm patient age 0 to 0 5 years 0 5 to 3 years 3 to 8 years 8 to 13 years 13 to 19 years elder than 19 years 2 4 4 2 Determination of individual effective doses E to patients using a dosimeter is carried out in compliance with methodic instructions for monitoring methods MUK 2 6 1 760 99 Determination of individual effective doses to patients during X ray examinations using dose area products meters The value of an effective dose E uSv to a patient of the given age when carrying out X ray examination is determined as follows E D Ki 2 1 where D is the measured value of the dose area product cGy cm Ka is the factor of conversion to the effective dose to a patient of the given age with taking into consideration the type of carried out X ray examination projection field size focal distance and anode voltage at the X ray tube uSv cGy cm Values for factors of conversion to the effective dose for X ray examination of different organs and systems are given in appendix 1 of MUK 2 6 1 17
4. no ANNA fhan measuring console narren nnee tenrek 90022080 mm ionization chamber pp 80x180x20 mm 1 2 28 Connecting cable length se tried ti a ie Peis no greater than 20 m 1 3 Product composition 1 3 1 The dosimeter consists of the light transparent ionization chamber measuring set henceforth referred to as a control panel and connecting cable extender to connect the chamber to the control panel 1 3 2 The ionization chamber is a plastic case into which a plexiglass plates are pasted and two conductive plates electrodes are mounted The communication cable with a measuring console is mounted into the case on a side panel The delivery set contains self tapping screws and a pair of metal clips slides by means of which the chamber is pushed into the latch mechanism of the X ray emitter aperture with a standard fastener system 1 3 3 The control panel is made as a separate ergonomic unit equipped with an integrated power cable power switch and grounding terminal The panel involves an electronic circuit for processing signals being received from the ionization chamber a display device and data output device integrated printer as a set DBKM 412113 017P3 4 1 4 Arrangement and operation 1 4 1 The light transparent plane parallel ionization chamber presents two electrodes with air filled space between them To one of the electrodes voltage of 400 V is applied and the second one is intended to collect charges electron
5. performing calibration Mandatory performance of Operati nes calibration facilities and their U peration name ph as number reference characteristics initial periodic calibration calibration 1 External examination 4 5 1 Visual Yes Yes 2 Testing 4 5 2 Yes Yes 3 Determination of intrinsic 4 5 3 Primary working standard of absorbed Yes Yes relative error of dose of photon radiation in air with an measurement ionization chamber according to GOST 8 70 96 X ray machine with tube voltage of 50 200 kV Auxiliary devices barometer according to GOST 23696 79 and thermometer according to GOST 27544 87 4 Processing of 4 6 Yes Yes measurement results 5 Drawing up of calibration 4 7 Yes Yes results Note You can use particular first developed or being in use facilities and equipment as long as those facilities and equipment have specifications at least as good as those listed in this verification procedure 4 3 Safety requirements When performing calibration safety requirements stated in 2 2 and documentation for calibration facilities and equipment employed should be followed 4 4 Calibration conditions Calibration should be carried out observing the following conditions er Ambient TEMPE ature sa aaa kaa a whieh aaa ga eaaa dag ag Hen aa kaba aa Pa a om aal a aa AG 20 5 C gt HEl VENIR aaa jasane ga aja dne aga Ba erde denten aderen ares 30 to 80 atmosphere p
6. 436210 OKP N EN SCIENTIFIC AND PRODUCING COMPANY O 034 DOZA CLINICAL X RAY DOSIMETER DRK 1 Operating manual DBKM 412113 017P3 Table of contents 1 Description and operation of the product onee eneen eneen eenen 3 1 1 Product desinat OA Ln nternet rn a aed ar ua eG 3 1 2 Techical Tavares oneness eerdere ents oneens 3 1 3 Product Compositi isseire aae a aer A e EAA ETE AEAEE es 4 1 4 Arrangement and operation pp 5 1 5 Marking and sealing wort avs Sexes enter ene E E T T E E 6 DOPAC i AA nee EU nn RED OE E 6 2 Intended ALTE 7 2 1 Operating limitations pt 7 2 2 Safety precautions when preparing the product for use ppp 7 2 3 Preparing the product for use bedrukte rte J 2 3 1 Placement ANG ASSCIMDIY vasa meenamen E E Kg a evans 7 2 3 2 Functional test of the dosimeter ppp 8 2 4 Ster op the product re oree ENE A Ta gg E EE E GP A NEG then EN EN ah aa a 8 2 4 1 Performing the measurements soon oenen een cence eee cnet eaaa eee 8 2 4 2 Sing date and UNE ae gate KAE ENG gga ekeren dites 9 2 4 3 Nonvolatile memory handling nerven ese eraa aen 9 2 4 4 Estimation of effective dose to a patient pp 10 2 4 5 Checking consistency of operation of X ray machines ppp 10 J MEINE eeren Ga Sai nan EEEE E aE EREE a OE EAE a a a a aa na a E Ta an 11 Sel Generdbanstruchons n aaa Aa a AN nanne 11 3 2 Safety prec ONS 45 Esa aa a NG ENG neren 11 3 3 Maintenance procedure Aare vandan aber saldo Sladen ne eee 11 4 Verification pr0CEdUTe sa
7. 97 03 2 4 4 3 The delivery set of the dosimeter in accordance with the order card may involve optional application software ASW DRK1 Agent and BD DOP or ASW DRK1 Monitor ASW DRK1 Agent is intended to transmit data from a dosimeter to a computer ASW BD DOP allows to automatically calculate individual radiation absorbed doses to patients fill and maintain databases on individual effective radiation doses to patients automatically fill in the form Ne 3 DOSE Data on radiation doses to patients during medical radiological and nuclear examinations ASW DRK1 Monitor comprises functions of both previous programs except for a feature of automatic filling of form Ne 3 DOSE To employ the ASW you need 1 install the given software on your computer 2 connect the dosimeter and computer using the communication cable RS 232 optionally involved in the delivery set in accordance with the order card If a standard connector RS 232 is not available use the USB RS 232 adapter optionally involved in the delivery set in accordance with the order card Installation and work with software are described in the user s guide optionally involved in the delivery set 2 4 5 Checking consistency of operation of X ray machines 2 4 5 1 The dosimeter may be used to check consistency of operation of X ray machines in the course of their use DBKM 412113 017P3 10 2 4 5 2 As a factor of consistency of operation of the X ray mach
8. a a Ng reed u ner stane 12 4 1 General reguirementS sanga D E aes vere Se TEE neede a 12 4 2 Operations and facilities of verification pp 12 4 3 Safety requirements dover iene E a aa a E a AN erde be aeta Meiden 13 4 4 Verification conditions RN 13 4 5 Performing the verification vuren soeren aaseter nent Ba AN Ga a a ens 13 4 6 Processing of measurement results ooa nende ranke hedde eee 14 4 7 Drawing up of verification results pp 14 S ROUtINE TEPAll tase NG a a Aa ANAA AAN KNA ATE TENE EEA T TER 14 6 SOLAS Cia ii aa A sigh E a ele bree add an 14 Li TANS POL AUN KAE EEE Osu sake a BA Na A ren eeen enb sad 15 S AE oa Saja aa aga a a ag GA a a a eather Ga a E cubs AS E KAG Ng TG a a aa ak aan 15 Appendix A Diagram of installing the clips on the ionization chamber pp 16 BKM 412113 017P9 2 This operating manual PBKM 412113 017P3 covers design operating principal characteristics of the product and indications necessary for proper and safe use of the product intended use maintenance routine repair storage and transportation and also information about utilization of the product 1 DESCRIPTION AND OPERATION OF THE PRODUCT 1 1 Product designation The clinical X ray dosimeter DRK 1 BKM 412113 017 henceforth referred to as the dosimeter is manufactured in compliance with the requirements of the technical conditions TU 4362 004 318673 13 98 and intended to measure the product of absorbed dose in air and cross section area of a
9. d mm yy dose area product Dose eGy cm space for the radiologist s signature After printing the measurement results the dosimeter readings are automatically cleared In memory time and date of the measurement its serial number among measurements carried out in the course of that day and dose area product value are saved The dosimeter allows to print data of any saved result Detailed description is given in point 2 5 2 4 1 3 If necessary to make several X ray exposures in the same projection do not clear display readings after each exposure If this the result of each subsequent measurement will be added to the preceding value The final result will be an accumulative value over all measurements of the dose area product 2 4 2 Setting date and time 2 4 2 1 This section is intended for specialists involved in service repair or adjustment of dosimeters Correctable parameters Minutes B0 Hours Bl Date B2 Month B3 Day B4 Year B5 2 4 2 2 To turn on the dosimeter put the power switch to the I position holding pressed the WORK key With this the message will be displayed 2 4 2 3 Press the SCROLL key With this the Bl message and astronomical time clock will appear To set the desired value use the U and fl keys 2 4 2 4 Press the SCROLL key twice again With this the B2 message and month number will appear Subsequent double pressings on the SCROLL
10. delay interval aaa eaaa eaaa anaa aaa aaa aaa eee no greater than 5 s 1 2 15 The dosimeter has an electrical operability and constancy monitoring system 1 2 16 POWER Supply pp 230 s V 505 Hz 1 2 17 Power consumption pp no greater than 50 VA 1 2 18 Nonvolatile memory size pp no greater than 100 measurements 1 2 19 Width of a printing paper saene aee 50 to 56 mm 1 2 20 The printer cartridge replacement life no less than 250 000 characters 1 2 21 Environmental climatic factor values while using the dosimeter under operating conditions in compliance with GOST 15150 69 operating temperature range mavensis 10 to 35 C limit value ofa relative humidity pp 75 at 35 C atmosphere pressure in the range of pp 84 0 to 106 7 kPa corrosion active agent content in air conforms to an atmosphere type I 1 2 22 The dosimeter is stable and strong against sine vibrations in the frequency range of 10 to 55 Hz with a bias amplitude of 0 35 mm 1 2 23 Protection level being provided by the dosimeter enclosure is IP40 according to GOST 14254 96 1 2 24 By level of protection against electrical shock the dosimeter is referred to class I according to GOST 12 2 007 0 75 1 2 25 By fire resistant features the dosimeter conforms to GOST 12 1 004 91 with a fire probability of no greater than 10 1 year 1 2 26 Weight of the dosimeter DO greater than 2 kg 1 2 27 Overall dimensions
11. e of operations 3 MAINTENANCE 3 1 General instructions 3 1 1 Maintenance of the dosimeter is carried out in order to provide its safety and serviceability over its total operation life 3 1 2 Maintenance of the dosimeter is performed only by personnel having familiarized with this manual 3 2 Safety precautions When performing maintenance of the dosimeter safety precautions stated in 2 2 must be strictly followed 3 3 Maintenance procedure 3 3 1 Maintenance of the dosimeter comprises preventive maintenance and current maintenance 3 3 2 Preventive maintenance is carried out before starting works and with this the following is examined DBKM 412113 017P3 11 external view of the dosimeter connecting cables fastening safety of the power cable insulation and availability of grounding 3 3 3 Current maintenance should be carried out once per week with this the following is performed cleaning of the external surface of the dosimeter removal of faults detected during operation replacement of a printer paper or cartridge To replace the printer paper it is necessary to 1 remove screws retaining the printer cover 2 withdraw the expended roll former and place the new one 3 cut smoothly the paper tape end using scissors and insert it into the reception slot of the printer 4 press the PAPER FEED key and wait unless about two centimeters of the paper tape come out the printer To replace the p
12. ered by waterproof material upon transportation by air the boxes with dosimeters should be situated in the airproof heated section upon transportation by water the boxes with dosimeters should be situated in hold sections 7 2 Placement and fastening of boxes with dosimeters in transportation facilities should provide steady position throughout the entire journey protection against lading shifts and impacts 7 3 When loading and unloading the inscription requirements stated on a shipping container should be observed During handling operations the dosimeter should not be subjected to effects of atmospheric precipitation 7 4 Transportation conditions 7 4 1 Values of environmental climatic factors in the course of servicing the dosimeter under workless condition transportation REL LN minus 25 to 50 C under condition of smooth temperature stabilization during unloading to temperatures of 10 to 35 C and further stay under normal conditions within 12 h humidity Seer a A eehter dede up to 98 at 35 C 7 4 2 The dosimeter in a shipping container is stable against sine vibrations in the frequency range of 10 to 55 Hz with a bias amplitude of 0 35 mm group N2 according to GOST 12997 84 8 UTILIZATION 8 1 On expiry of total life time the dosimeter must be dismantled to exclude possibility of its further use and sent to specially conditioned places in waste disposal spaces DBKM 412113 017P3 15 Appendix A recommended
13. h the key pressed in the standby mode scroll through saved in memory parameters of the processes carried out The fl and U keys is designed to decrement increment the selected parameter in the setup mode scroll through the records while scanning memory The STORAGE key provides changeover from the standby mode to the memory scan mode The PRINT key provides printing of the last measurement results or printing of the record selected while scanning memory The RESET key is designed to clean the dosimeter readings and switch to the measurement mode reset the system in case of hang up hang up symptom glowing single digit on the display or completely dim display The TEST key provides preliminary functional test of the dosimeter The PAPER FEED key provides paper feed in the printer 1 4 5 The display shows dosimeter measured dose area product value under normal operation or in the memory scan mode dosimeter settings in the date and time setting mode error message if appears during functional test of the dosimeter DBKM 412113 017P3 5 PAPER FEED DOSE cGy cm AE E SCROLL to O a Be MEDICAL X RAY DOSEMETER VAN www doza ru Figure 1 1 Key arrangement on a control panel 1 5 Marking and sealing 1 5 1 The case of products involved in the dosimeter contains the following markings trade mark and or manufacturer s name reference designation of the do
14. he dosimeter sensitivity on radiation energy in the operating range of anode voltages of the X ray emitter pp no greater than 25 1 2 5 The dosimeter sensitivity 1 min later after power up differs from this 15 min later after BOWEL UD POr m ka ices iy Sasi La Na Ween st aac wate Mie A eee bede no greater than 10 1 2 6 Change of the dosimeter sensitivity depending on the irradiated area no greater than 5 1 2 7 Dependence of the dosimeter sensitivity on absorbed dose rate no greater than 10 1 2 8 Uniformity of the dosimeter sensitivity over the ionization chamber area no less than 95 1 2 9 Leakage current of the ionization chamber provides the reading increment for 1 h of work in the absence thereof an external radiation exposure pp no greater than 1 cGy cm 1 2 10 Transparency of the ionization chamber for visible light no less than 70 1 2 11 Attenuation equivalent of the ionization chamber at the anode voltage of 100 kV percentage ripple of the production voltage is no greater than 10 of the overall filtration of 2 mm dba tena area a kak Mousa ets Se Delta a ule etek tenet Lalit no greater than 0 5 mm Al 1212 Ware Up DNG eerden enn chaste tener eeh no greater than 1 min 1 2 13 Measurement of the dose area product using the dosimeter is synchronized with work of the X ray machine with this continuous operation time ppp no less than 6 h DBKM 412113 017P3 3 1 2 14 Data
15. heck connection of the ionization chamber connecting cables and connectors and turn on the dosimeter again If the test fails again contact the manufacturer or repair service 2 3 2 4 In case of successful test go to measurements 2 3 2 5 When turning on the dosimeter for the first time after 1 transportation and long term storage 2 change of climatic conditions 3 long term outage 4 mounting or replacement of the connecting cable in the X ray machine ATTENTION WARM UP TIME MAY BE 15 30 MIN I E WHEN PRESSING THE RESET KEY ON EXPIRY OF THAT TIME ZERO READINGS P 0 0 SHOULD APPEAR ON THE DISPLAY AND THEY SHOULD REMAIN INVARIABLE UNTIL RADIATION IS APPLIED TO THE CHAMBER DURING FURTHER USE THE WARM UP TIME SHOULD BE IN ACCORDANCE WITH TECHNICAL CHARACTERISTICS 2 4 Use of the product 2 4 1 Performing the measurements 2 4 1 1 To start the new measurement resetting the display readings press the RESET key on the front panel of the control panel The dosimeter starts measurement after changing first two readings of the display 2 4 1 2 On expiry of exposure time X ray exposure time on the control panel display the dose area product value cGy cm will appear To print the result press the PRINT key With this the result is printed on a form and saved in memory The form contains the following information dosimeter number DBKM 412113 017P3 8 procedure number time hh mm yy date d
16. ine the discrepancy of the ratio value of a mean dose area product deviation and mean dose area product value S over specified time intervals is used To calculate this it is necessary to 1 take five readings of a dosimeter at different settings mAs at a specified value of tube voltage and with an aperture maximum opened Most high usage settings mAs in the operating range are recommended 2 determine the mean dose area product value over five readings for all chosen settings mAs D using the equation pj Ds 2 2 where D is the i th one from five values of the dose area product at the j th setting mAs 3 calculate the mean dose area product deviation at each setting mAs 6 5 De Dy ZD c j 62 SH 2 3 Pj 5 cp j gt USINg the equation 4 calculate the ratio of the mean dose area product deviation and mean dose area product at all settings mAs S using the equation 6 SL 2 4 2 4 5 3 The calculations within this procedure should be made separately for minor and major focuses 2 4 5 4 Check of operation consistency of X ray machines is carried out by comparing the values S obtained at the commencement of operation with values S obtained after 6 month j intervals The values S for the same setting mAs should not differ more than for 25 Otherwise the X ray machine may be faulty The actions that personnel should perform in such situation are described in the appropriate schedul
17. key allows to select the following parameters B3 month B4 day B5 year BO minutes and B1 current time value again by cycle To set the desired value use the ll and fl keys 2 4 2 5 To quit the time setting mode cancel the point on the third position of the display by pressing the SCROLL key once ATTENTION THE DOSIMETER SOFTWARE DOES NOT PROVIDE CHECKING THE CORRECTNESS OF SETTING THE PARAMETERS 2 4 3 Nonvolatile memory handling 2 4 3 1 The dosimeter has a nonvolatile memory that allows saving up to 100 measured data Besides a nonvolatile real time timer involved in the dosimeter set allows to state date and time of each measurement 2 4 3 2 To work with measurements saved in memory press the STORAGE key on the front panel of the control panel With this the serial number of the last measurement for the current day and time of the measurement will appear Using the fl and U keys you may view the measurement performance chart When pressing the SCROLL key the dose area product obtained during this measurement will be displayed when pressing the key twice date relevant to this measurement will appear To leave the memory handling mode press the WORK key DBKM 412113 017P3 9 2 4 4 Estimation of effective dose to a patient 2 4 4 1 Source information for estimation of effective dose to a patient using a dosimeter is as follows anode voltage value at the X ray tube kV thickness
18. lips slides from the delivery set on the ionization chamber case using self tapping screws Diagram of installing the clips on the ionization chamber is given in appendix A Distance between guides and their orientation may be changed by loosing the self tapping screws 2 3 1 4 Gently push slides of the ionization chamber into the latching mechanism of the X ray emitter aperture 2 3 1 5 Connect the ionization chamber to the control panel inserting the cable connector of the ionization chamber into the CHAMBER 1 or CHAMBER 2 socket on the backside of the control panel 2 3 1 6 Connect the power cable plug to mains With this the power switch located on the side panel of the control panel should be in the 0 position Check if the power cable is properly connected and has no damages Check if grounding is available 2 3 1 7 Put the power switch located on the side panel of the control panel to the I position With this indicators on the front panel should lit and after the readings in first two digits of the display change the zero readings P 0 0 will be set 2 3 2 Functional test of the dosimeter 2 3 2 1 Warm up the dosimeter within min 2 3 2 2 Press the TEST key on the front panel with this change of readings in first two digits occurs after then the zero readings will be reset if the test result is successful or Er if failure is detected 2 3 2 3 In case of test failure disconnect the dosimeter from mains c
19. n X ray beam at the X ray machine output henceforth referred to as the dose area product estimate the effective dose to the patient during X ray diagnostics and roentgenotherapy using the appropriate procedures control consistency of operation of X ray machines in the course of their use The dosimeter is a fixed lab measuring instrument and is used in medical institutions for all basic types of Russian and foreign X ray machines radiological photofluorographic surgical angiographic mobile except for dental mammographic and tomographic X ray machines The dosimeter has an integrated printer to print measurement results on a paper tape The dosimeter may be used with two ionization chambers at once With this the second ionization chamber operates in the accumulation mode as well as an independent measuring channel The dosimeter has a feature of data transfer through information links and provides access to the processed data via the RS 232 interface based links 1 2 Technical features 1 2 1 Operating range of anode voltages of the X ray emitter is 30 to 200 kV 1 2 2 Range of the detected dose area product pp 1 to 10 cGy cm 1 2 3 Limits of a relative intrinsic error of the dose area product measurement for a confidence probability of 095 anemoon den Wainnalete damned ennen 15 35 D where D is a non dimensional quantity that is numerically equal to the dose area product value in cGy cm 1 2 4 Dependence of t
20. replaced Do not remove the pin plug holding the cord 2 2 8 Never let the communication cable to be squeezed Be particularly careful when cabling in the area where the X ray machine stand moves 2 2 9 Be sure to disconnect the AC cable from mains when replacing fuses as well as the printer cartridge or paper roll Never open the dosimeter sooner than 10 minutes after power off Be sure to install fuses of the stated rate and type WARNING NEVER WORK WITH THE DOSIMETER WITH COVERS AND HOUSING REMOVED 2 2 10 Should contingency such as inflammation of the dosimeter technique or ingress of water into enclosure mechanical damage of the ionization chamber occurs immediately switch off and disconnect the power cable from mains Take appropriate steps keeping in mind that use of the dosimeter under extreme conditions may result in electric shock 2 3 Preparing the product for use 2 3 1 Placement and assembly 2 3 1 1 Unpack the dosimeter Make sure that completeness of the set conforms to the equipment certificate DBKM 412113 017IIC Check safety of the manufacturer s seals absence of damages of the dosimeter technique and conformance to factory numbers recorded in the equipment certificate DBKM 412113 017P3 4 2 3 1 2 The dosimeter should be grounded using grounding terminals on the backside of the control panel Grounding should be made regardless of degree of the space hazard in which the dosimeter is mounted 2 2 1 3 Fasten the metal c
21. ressure Ne 84 to 106 7 kPa natural radiation background pp no greater than 0 2 uSv h 4 5 Carrying out calibration 4 5 1 External examination With external examination the following should be ascertained compliance of completeness of the dosimeter under calibration with technical description availability of maintenance documentation absence of dirt mechanical damages on the instrument measuring console and ionization chamber of the dosimeter affecting its operation availability of mark of previous verification 4 5 2 Testing Testing of the dosimeter consists in performing operations described in 2 3 4 5 3 Determination of intrinsic relative error of measurement Calibration of the dosimeter is performed either with dismantling or without dismantling DBKM 412113 017P3 13 4 5 3 1 Upon calibration with dismantling the dosimeter an ionization chamber of the dosimeter under calibration is placed in the center of radiation field of the X ray machine so as its plane would be perpendicular to the beam axis and radiation field would cross all over the ionization chamber Radiation field non uniformity within the area of the ionization chamber should be within 5 The value of absorbed dose in air is determined using the primary working standard the ionization chamber of which is placed near the ionization chamber to be verified To convert measurement units of the reference dosimeter the ionization chamber to be
22. rinter cartridge it is necessary to 1 remove the old cartridge 2 place the new cartridge instead 3 make sure that the ink ribbon is not jammed and completely enters into the slot between the type drum and printing head 4 secure the cartridge on the latches 5 rotate the printer axis in the direction indicated by an arrow to withdraw an excess ribbon 6 return the printer cover and fasten the screws 4 CALIBRATION PROCEDURE 4 1 General requirements 4 1 Calibration of the dosimeter should be carried out by territorial organs of the National metrology services or other legally authorized organizations having power of carrying out this kind of works Requirements for management calibration routine and form of presenting the calibration results are specified in PR 50 2 006 94 National system for ensuring traceability Procedure of performing calibration of measuring instruments All first produced dosimeters dosimeters which have undergone repair and dosimeters being in normal use are subject to calibration Initial calibration covers the first produced dosimeters and those which have undergone repair Periodic calibration covers the dosimeters being in normal use Re calibration period is one year 4 2 Operations and facilities of calibration When performing calibration operations and facilities listed in Table 4 1 should be employed DBKM 412113 017P3 12 Table 4 1 List of operations and facilities employed when
23. s having formed in the chamber under exposure to the ionizing X ray radiation Under exposure to X ray ionizing current flows through the chamber Charge having transmitted through the chamber in the course of exposure is proportional to the dose area product 1 4 2 Charge having transmitted through the chamber charges a capacitor situated in the control panel Capacitor voltage is measured with an electronic voltmeter made using an analog to digital converter ADC Data on achieved voltage and accumulated charge Q CU where Q is a capacitor charge C is a capacitor capacity U is a capacitor voltage enter to the control panel microprocessor where upon them the dose area product is calculated 1 4 3 Wide measurement range of the dose area product is reached by installing into the control panel some capacitors of different capacities differing in order As the charge of the preceding capacitor reaches the reference voltage charge from the chamber will begin to be applied to the second capacitor and so on until all the charge having transmitted through the chamber will be accumulated on the capacitors 1 4 4 The front panel of the dosimeter control panel houses the control keys Figure 1 1 shows a key arrangement on a control panel The WORK key provides entry to the date and time setting mode reset to the normal standby mode The SCROLL key is designed to select time parameters in the setup mode view the date wit
24. simeter serial number according to manufacturer s numbering system mark ofpattern approval year of manufacture power voltage or current frequency 1 5 2 Position and method of marking type size meet the requirements stated in the design documentation 1 5 3 Sealing of the dosimeter is performed in compliance with the design documentation 1 6 Packing 1 6 1 The dosimeter is packed to meet the requirements for category KU 3 according to GOST 23170 78 1 6 2 The inner package of the dosimeter meets the requirements of GOST 9 014 2005 for group III protection version V3 10 packing version VU 5 Protection period without re conservation is 3 years 1 6 3 Packing is performed in closed ventilated spaces with an ambient temperature of 15 to 40 C and relative humidity up to 80 at 20 C and corrosion active agent content in air not exceeding this specified for atmosphere of type I by GOST 15150 69 DBKM 412113 017P3 6 2 INTENDED USE 2 1 Operating limitations 2 1 1 The dosimeter stays operable under conditions described in 1 2 2 1 2 Care should be taken to protect the dosimeter against undesirable weather impacts increased humidity of air temperature jumps 2 1 3 Do not install the control panel near radiators and heaters 2 1 4 When cracks or chips appear on the ionizing chamber case further use of the chamber is forbidden 2 1 5 The ionizing chamber should not shift in the guide slides of the X ray aper
25. ture more than for 2 mm under any position of the X ray emitter 2 2 Safety precautions when preparing the product for use 2 2 1 Personal continuously or temporarily involved in handling the sources of ionizing radiation must follow requirements stated in Principal Sanitary Radiation Safety Rules OSPORB 99 SP 2 6 1 799 99 and Radiation safety standards NRB 99 SP 2 6 1 758 99 2 2 2 Failure of the dosimeter does not pose irradiation hazard since there is no an electrical connection to the X ray machine control circuits 2 2 3 Maintenance of the dosimeter should be performed in compliance with Rules of technical operation with consumers electrical installations and Safety rules for operation with consumers electrical installations 2 2 4 Only properly trained and having electrical safety qualification level HII personnel are allowed to perform repair and adjustment of the dosimeter 2 2 5 Before turning on the dosimeter make sure that insulation of a power cable is safe and grounding is available 2 2 6 The dosimeter must be safely grounded Grounding should be made regardless of degree of the space hazard in which the dosimeter is mounted Protective grounding must enabled first and disables last after the supply voltage is off 2 2 7 In case if insulation fault or electric circuit failure occurs immediately stop use of the dosimeter and switch it off The damaged power cable should be disconnected from mains and
26. verified should be closed against radiation by a metal screen with a window of the known area With this dose measured with the working standard is assumed to be the estimated value of readings of the dosimeter under verification The calibration is carried out at the anode voltage of 100 kV The ionization chamber is exposed to doses producing values of the product of dose Do and chamber area S equal to about 25 300 2000 and 10000 cGy em 4 5 3 2 Upon calibration without dismantling as a primary working standard the working standard based on the clinical X ray dosimeter DRK 1 is employed If this verification is carried out by a comparison method in accordance with Procedure of periodic calibration without dismantling involved in the delivery set of the working standard 4 6 Drawing up of measurement results Intrinsic relative error of measurement of the dose area product is calculated in percents as follows NB 100 4 1 0 where D is the measured value of the dose area product cGy cm Do is the estimated value of the dose area product cGy cm Results of the calibration are considered to be satisfactory if the limits of an intrinsic relative error of measurement of the dose area product meet the requirements stated in 1 2 3 4 7 Drawing up of calibration results 4 7 1 Satisfactory results of calibration of dosimeter are drawn up in accordance with PR 50 2 006 94 4 7 2 Upon unsatisfactory results of calibration
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