User Manual. RW3 Slab Phantom T29672 and T

Transcription

1 User Manual RW3 Slab Phantom Contents Operating Manual Technical Manual Service Manual D /07 en Hn

2 General Information General Information The product bears the CE-mark "CE" in accordance with the Council Directive 93/42/EEC about Medical Devices and fulfills the essential requirements of Annex I of this directive. The product is a class I device without a measuring function (MDD). The user manual is an integral part of the product. It should always be kept near the product. Observance of the manual is a prerequisite for proper product performance and correct operation. Operator safety, specified measuring accuracy, and interference-free operation can only be guaranteed if original products and parts are used. Furthermore, only the accessories listed in this manual are approved by PTW-Freiburg and only they or other accessories whose use has been expressly permitted by PTW-Freiburg may be used in conjunction with the product. Safe operation and proper product performance are not guaranteed if accessories or consumables from other manufacturers are used. PTW-Freiburg cannot be held liable for damage resulting from the use of accessories or consumables from other manufacturers or when the user ignores the instructions and information given in this manual. In case of any questions concerning the service, support, or warranty, please contact your supplier. This manual is in conformity with the product specifications and all applicable safety standards that are valid as at the printing date. All rights are reserved for devices, circuits, techniques, software, and names as referred to in the manual. PTW-Freiburg reserves the right to make modifications. Please contact PTW or your local representative for the most current information concerning the products of interest. No part of the technical documentation may be reproduced without written permission from PTW-Freiburg. PTW-Freiburg is a registered manufacturer according to the ElektroG (Elektro- und Elektronikgeräte-Gesetz). Elektro-Altgeräte-Register (EAR). Registration number DE PTW-Freiburg works in strict accordance with a quality management system that is continuously updated according to the national and international standards. The warranty period is 1 (one) year and begins on the day of delivery. It is unaffected by repairs covered by the warranty regulations. PTW-Freiburg only considers itself responsible for the safety, reliability, and performance of the product if the assembly, extension, readjustment, modification, or repair is carried out by PTW-Freiburg or by persons authorized by PTW-Freiburg, and if the product is used in compliance with the technical documentation. 2 D /07 en

3 General Information PTW-Freiburg Physikalisch-Technische Werkstätten Dr. Pychlau GmbH Lörracher Str FREIBURG Germany Tel.: Fax: info@ptw.de D /07 en 3

4 Table of Contents Table of Contents General Information...2 Table of Contents... 4 List of Figures...5 Intended Use... 6 Safety Information... 7 Operating Manual Phantom Components Phantom and Chamber Plates Additional Plates Setting Up the Phantom Notes on Performing Measurements General Information on Performing Measurements Field Inhomogeneity Notes on the Use of RW3 for Measurements "in Water" Correction Factors for Photons Correction Factors for Electrons Comparative Measurements in RW3 and Water Technical Manual Technical Specifications D /07 en

5 List of Figures Service Manual Cleaning Preventive Maintenance Storage Disposal of the Product Literature...36 Index...37 List of Figures Figure 1: Definition of the patient environment...9 Figure 2: Inserting/removing the Roos chamber...12 Figure 3: Twin plate with inserted Roos chamber Figure 4: Correction factor h w/m as a function of depth for the field size 10 cm x 10 cm Figure 5: Correction factor h w,m as a function of depth for the field size 25 cm x 25 cm Figure 6: Correction factor h w/m in the maximum of depth dose distribution as a function of electron energy Figure 7: Slab phantom (height in mm)...30 Figure 8: Drawing of chamber plate for T29672 (dimensions in mm)...30 Figure 9: Drawing of chamber plate for T (dimensions in mm) D /07 en 5

6 Intended Use Intended Use The RW3 1) slab phantoms T29672 and T are solid state phantoms for use in radiotherapy. The phantoms are intended for use in energy ranges from 60 Co to 25 MV photons and 5 MeV to 25 MeV electrons. The RW3 slab phantoms T29672 and T will be referred to as phantoms in the following chapters. A differentiation between the RW3 slab phantoms T29672 and T is only made when necessary due to technical differences. 1) polystyrene with a mass percentage of 2% TiO 2 6 D /07 en

7 Safety Information Safety Information This is the safety alert symbol. It is used to alert the user to potential hazards. Obey all safety messages that follow this symbol to avoid any possible bodily injury or equipment damage. All safety messages consist of the following components: Safety alert symbol and signal word Type of danger Source of danger Consequence Measures to prevent hazards. Signal Words DANGER Indicates an imminent hazard. If not avoided, the hazard will result in death or serious injury. WARNING Indicates a hazard. If not avoided, the hazard can result in death or serious injury. CAUTION Indicates a potential hazard. If not avoided, the hazard can result in minor or moderate injury. NOTICE Indicates a potential hazard. If not avoided, the hazard can result in product damage. HINT Provides application tips or other useful information to ensure that you get the most from your equipment. D /07 en 7

8 Safety Information Safety Information Strictly observe the following safety information concerning the signal word WARNING. Failure to do so may endanger the lives of the patient, the user, and other persons involved. WARNING Improper handling. Hazards to Persons! The product is a medical device and must only be handled by persons who are trained in the use of such equipment and are capable of applying it properly. The operator must be trained in the use and operation of the product. WARNING Application for uses other than those stated in the user manual. Bodily Injury! Equipment Damage! WARNING Use of the product when it is not in perfect operating condition. Bodily Injury! Equipment Damage! Before using the product, verify that it is in correct working order and operating condition. Liquids must not enter the product. If liquids have entered the product, dry the product or wait for it to dry completely. The product must be thoroughly inspected by service personnel before being used again. WARNING Hazards originating from other system components. Hazards to Persons! Equipment Damage! Observe the safety information provided in the user manuals of the system components. Always apply the product in compliance with its intended use. Failure to do so may lead to severe or even fatal injuries and/or equipment damage and may void the warranty. Exclusion of operation in the patient environment: Do not operate the product in the patient environment (refer to Figure 1). 8 D /07 en

9 Safety Information CAUTION Use of the product without observing the user manual. Bodily Injury! Equipment Damage! Always use the product in compliance with the user manual. Otherwise, the provided protection may be impaired. Use the product only in conjunction with the products approved by PTW for this purpose and/or the products listed in the section "Intended Use". NOTICE To prevent equipment damage, always employ the product as instructed in the user manual: Operate the product within the rated ranges of use indicated in the "Technical Specifications". Handle the product with care. Figure 1: Definition of the patient environment D /07 en 9

10 Safety Information Symbols on the Nameplate Symbol Description Refer to the user manual! The product bears the CE-mark. Manufacturer and date of manufacture Reference number Serial number For a description of additional symbols, if applicable, please refer to the equipment description. 10 D /07 en

11 Operating Manual - Phantom Components Operating Manual 1 Phantom Components 1.1 Phantom and Chamber Plates The RW3 slab phantom T29672 consists of 33 RW3 phantom plates of 30 cm x 30 cm each. The RW3 slab phantom T consists of 33 RW3 phantom plates of 40 cm x 40 cm each. The phantom plates have the following thicknesses: 1 phantom plate, 1 mm thick 2 phantom plates, 2 mm thick 1 phantom plate, 5 mm thick 29 phantom plates, 10 mm thick The carrying case T2967/12 can accommodate a complete set of phantom plates measuring 30 cm x 30 cm. HINT Check that the plates are properly stored to ensure their planarity (refer to section 7 "Storage"). By combining phantom plates of different thicknesses, measurements can be taken at any depth up to 30 cm in steps of 1 mm. Numerous plates are additionally available into which chambers can be inserted without air gaps (refer to section 4 "Technical Specifications"). D /07 en 11

12 Operating Manual - Phantom Components 1.2 Additional Plates Twin Plate for Roos Chamber A Roos chamber type can be inserted into the twin plate T29672/U20 or T The effective point of measurement (reference point) of the detector in this plate is approximately 1 mm below the surface of the twin plate. NOTICE To prevent equipment damage, do not pull on the cable when removing the detector. Lift off the plate with the crosshairs and carefully remove the detector (refer to Figure 2). Inserting the Roos chamber Insert the detector in the twin plate so that the crosshairs is visible and points towards the radiation source (refer to Figure 2 and Figure 3). Figure 2: Inserting/removing the Roos chamber Figure 3: Twin plate with inserted Roos chamber 12 D /07 en

13 Operating Manual - Setting Up the Phantom Twin Plate for Markus Chamber and Advanced Markus Chamber A Markus chamber type or an Advanced Markus chamber type can be inserted into the twin plate T29672/U10 or T The reference point is approximately 0.4 mm below the surface of the twin plate. For information about the location of the effective point of measurement, please refer to the user manuals of the chambers. 2 Setting Up the Phantom The alignment of the phantom in the radiation beam can be verified by means of the crosshairs on the plates. Using plates of different thicknesses, the measuring depth can be varied in steps of 1 mm. Check that the phantom is set up at an adequate source-surface distance. Select the minimum field size that ensures homogeneous irradiation of the detector at all depths. The field size can be checked by attaching an X-ray film in a suitable cassette to the surface of the phantom and comparing the blackened area with the position of the phantom. If a large number of plates is required for the measurements, the user must make sure that the surface on which the phantom is located is adequate to bear the overall weight of the phantom and chamber plates used and of the measuring devices. Refer to the Technical Specifications section in the user manuals for details. HINT For phantoms exposed to temperature changes, allow sufficient time for temperature equalization (refer to section 7 "Storage"). D /07 en 13

14 Operating Manual - Notes on Performing Measurements 3 Notes on Performing Measurements 3.1 General Information on Performing Measurements The phantom can be used for depth dose measurements and for the calibration of thimble and plane-parallel chambers in the unit absorbed dose to water and in the energy range from 60 Co gamma radiation to 25 MV photons and in the range from 5 MeV to 25 MeV electrons. The calibration of the chamber of interest within the phantom can be performed with 60 Co gamma radiation by comparison of a reference chamber with the chamber to calibrate. This means that both chambers will be irradiated one after the other with identical geometries. For calibration with bremsstrahlung, make sure that the tube voltage provided by the X-ray system or the voltage of the accelerator is almost constant. When performing measurements against a monitor with the monitor chamber located in air between the source and the chamber to be calibrated inside the phantom, minor changes of the tube voltage will affect the bremsstrahlung spectrum, changing the absorption between the monitor in air and the chamber to be calibrated at a given depth. 3.2 Field Inhomogeneity Using special adapters, it is possible to perform simultaneous measurements with multiple chambers. If more than one chamber is inserted, the chamber positions should be changed because field inhomogeneities may exist and in order to obtain equivalent doses when comparing the chambers. If chambers of different designs are used simultaneously, the possible mutual influences of the radiation field should be considered. If chambers of the same design are used, this is not required because the mutual influences are identical for both chambers. HINT Different scatter characteristics due to different chamber designs can be investigated by calibrating the chambers against a monitor transmission chamber. When this method is used, however, it is imperative to use a constant radiation quality (see above). When irradiating different chambers, a sufficiently large field size must be ensured. 14 D /07 en

15 Operating Manual - Notes on Performing Measurements 3.3 Notes on the Use of RW3 for Measurements "in Water" Water is the standard reference material for highenergy photon and electron dosimetry and it should be used for the first dosimetry or reference dosimetry. In many routine applications or for constancy tests, however, working with a waterequivalent solid state phantom is often more convenient. RW3 consists of white polystyrene with a mass percentage of 2% TiO 2. RW3 was developed for use as a water-equivalent solid state material for dosimetry of high-energy photon and electron beams. Different admixtures of TiO 2 where systematically investigated in order to optimize the material for dosimetry applications (refer to "Literature" [10]). The density of RW3 is g/cm³, the effective material parameter (Z/A r ) eff is and the electron density is higher than that of water by a factor of For dosimetry purposes, material equivalence means that the absorption and scatter characteristics with respect to photons and electrons must be the same in both materials. The effective atomic number of polystyrene, which is lower than that of water, can partly be compensated by the high atomic number of TiO 2. Due to the energy dependence of the absorption and scatter coefficient, it is understandable that this compensation cannot be achieved over the full energy range in which dosimetry can be performed for highenergy radiation. Different experimental setups have been developed in order to investigate material equivalence and determine correction factors (refer to "Literature" [5], [9], [10], [11]). D /07 en 15

16 Operating Manual - Notes on Performing Measurements 3.4 Correction Factors for Photons Measurement of the Absorbed Dose to Water for Photons 2) If RW3 is used as water-equivalent solid state material, i.e., if the measured values are multiplied by the same correction factors used for dose measurements in water, each difference in the measurement of ionization in water and RW3 results in a corresponding difference of the absolute energy doses in both materials. It is a known fact that ionization in clear and white polystyrene is inferior to that in water. Deviations of up to 5% have been published (refer to "Literature" [8], [12]). For this reason, a correction factor h w/m is introduced that is affected both by the energy and by the measuring depth and field size h w/m = M w /M m M w and M m are the indications of the depth dose distributions in water and in polystyrene. Figure 4 and Figure 5 show this correction factor for four different radiation qualities and two field sizes as a function of the depth. The result of Figure 4 and Figure 5 is affected by a number of parameters, such as the type of ionization chamber used, the spectral distribution of the photons at the point of measurement, and further variables. Therefore, it is very important to verify these parameters for the particular measurement conditions (refer to section 4 "Technical Specifications"). 2) According to the current version of the standard DIN (2008), absolute dosimetry is only allowed in water. 16 D /07 en

17 Operating Manual - Notes on Performing Measurements Photons, field size 10 cm x 10 cm Correction factor h w/m Measuring depth in mm Figure 4: Correction factor h w/m as a function of depth for the field size 10 cm x 10 cm Photons, field size 25 cm x 25 cm Correction factor w/m Measuring depth in mm Figure 5: Correction factor h w,m as a function of depth for the field size 25 cm x 25 cm D /07 en 17

18 Operating Manual - Notes on Performing Measurements Relative Dosimetry for Photons The measured values of Figure 4 and Figure 5 can also be used to determine the deviation of TMR curves or relative depth dose distributions in water and in RW3. A correction factor that does not change with the measuring depth will not cause any deviations in relative measurements. It can be shown that the percentage deviation of TMR curves Δ(z) (normalized to the maximum dose) corresponds approximately to a depth z: Δ(z) = (h w/m (z) - h w/m (z max )) TMR(z) (2) where h n/m (z max ) is the correction factor at the maximum dose. For TMR(z) the value can be determined in water or in RW3. If, for a given radiation quality, the known TMR data are compared with the data of Figure 4 and Figure 5, the percentage deviation found does not exceed 0.5 % (4 MV), 0.4 % (6 MV), and 0.3 % (15 and 25 MV) at a field size of 10 cm x 10 cm. The values are marginally higher at a field size of 25 cm x 25 cm: 0.7 % (4 MV), 0.6 % (6 MV), and 0.5 % (15 and 25 MV). Take the determination of the quality factor Q in measurements in RW3, for example. The deviation from Q is less than 0.6 % (4 MV), 0.4 % (6 MV), and 0.2 % (15 and 25 MV), which causes a deviation of the ratio of the collision stopping powers of water and air (s w,air ) of approximately 0.03 % (4 MV and 6 MV), 0.04 % (15 MV), and 0.05 % (25 MV). 3.5 Correction Factors for Electrons Measurement of the Absorbed Dose to Water for Electrons 3) Due to its smaller scattering power related to the solid angle, the absolute ionization of RW3 is too low. The same correction factor h w/m used for photons can be introduced: h w/m = M w (z max )/M m (z max ) (3) M w (z max ) and M m (z max ) are the indications at the maximum dose in water and RW3. The energy dependence of this correction factor is shown in Figure 6. The illustration represents the results published in the literature (refer to "Literature" [7]). As mentioned above for photons, the measured values of Figure 6 depend on the type of ionization chamber, scattering screens, applicator type, field size, energy, and scattering of electrons and other particles referred to the solid angle. Therefore, it is very important to verify these measurement conditions for the particular radiation quality (refer to section 3.6 "Comparative Measurements in RW3 and Water"). 3) According to the current version of the standard DIN (2008), absolute dosimetry is only allowed in water. 18 D /07 en

19 Operating Manual - Notes on Performing Measurements Electrons, field size 10 cm x 10 cm Correction factor h w/m Electron energy in MeV Figure 6: Correction factor h w/m in the maximum of depth dose distribution as a function of electron energy D /07 en 19

20 Operating Manual - Notes on Performing Measurements Relative Dosimetry for Electrons For electrons with energies between 5 MeV and 25 MeV, some authors have shown that deviations in transversal dose distributions are negligible (refer to "Literature" [10], [13], [15]). Deviations of less than 1 mm have been stated. This implies that energy-dependent parameters can be determined with sufficient accuracy in RW3. They show a tendency to minimally overrate the values. 3.6 Comparative Measurements in RW3 and Water The water-equivalent RW3 phantom material can be used instead of water both in high-energy photon and in electron dosimetry. Relative transversal dose distributions measured in RW3 are in good agreement with measurements in water. For determination of the absolute dose, a correction factor greater than 1 must be applied to photons as well as to electrons. This correction factor depends on numerous parameters, such as energy and spectral distribution, measuring depth, field size, type of ionization chamber, and additional factors. Therefore, users are advised to consider the measurement results shown here only as a guideline. Reference measurements should be performed under routine conditions. For this, a number of points must be considered: The water phantom and the RW3 plates must have reached a temperature equilibrium. Evaporation of water lowers its temperature and can also reduce the measuring depth of the chamber in the water. The true thickness of the RW3 plates must be known. Air gaps may be present between RW3 plates if the plates are not completely flat. Measurements with a constant source-surface distance have a particularly strong influence on the source-detector distance. The long-term stability of the dosimetry system must be verified. 20 D /07 en

21 Operating Manual - Notes on Performing Measurements HINT Long-term irradiation may cause electrostatic charges in the solid state material. To prevent erroneous measurements due to the effects of static charges, only plates with a maximum thickness of 10 mm are available. The plates should be discharged by passing a metal object connected to ground potential regularly over the plates when doses of approximately 40 Gy or above are measured in the phantom. D /07 en 21

22 Operating Manual - Notes on Performing Measurements 22 D /07 en

23 Technical Manual - Technical Specifications Technical Manual 4 Technical Specifications Only values with specified tolerances or limits are guaranteed. Values without tolerances are for informational purposes only. Device designation Manufacturer Application Measuring depths Material Phantom and chamber plates RW3 slab phantom T29672 RW3 slab phantom T PTW-Freiburg water equivalent phantom material for dosimetry in high energy photon and electron beams up to 30 cm in steps of 1 mm RW3 (polystyrene (C 8 H 8 ) containing 2 % (± 0.4 %) TiO 2 ) Density RW g/cm 3 Electron density times higher than electron density of water Mean value (Z/A r ) eff Dimensions Weight Phantom Chamber plates Storage case T2967/U12 Rated range of use Radiation quality Temperature Relative humidity Atmospheric pressure Maximum operating altitude refer to tables T29672: approx. 30 kg T : approx kg for T29672: approx. 1.9 kg (average value) for T : approx. 3.3 kg (average value) für T29672: 8.2 kg Photons: 60 Co MV Electrons: ( ) MeV ( ) C / ( ) F (10 80) %, no condensation (max. 20 g/m³ absolute humidity) ( ) hpa 3000 m above sea level D /07 en 23

24 Technical Manual - Technical Specifications Device designation Environmental conditions for transport and storage Temperature Relative humidity Atmospheric pressure RW3 slab phantom T29672 RW3 slab phantom T ( ) C / ( ) F (10 85) %, no condensation (max. 20 g/m³ absolute humidity) ( ) hpa 24 D /07 en

25 Technical Manual - Technical Specifications Phantom plates of T29672 Reference number Product Dimensions Tolerance of plate thickness T29672/1 RW3 plate 300 x 300 x 10 mm (300 x 300 x 10) mm ±0.1 mm T29672/2 RW3 plate 300 x 300 x 5 mm (300 x 300 x 5) mm ±0.1 mm T29672/3 RW3 plate 300 x 300 x 2 mm (300 x 300 x 2) mm ±0.1 mm T29672/4 RW3 plate 300 x 300 x 1 mm (300 x 300 x 1) mm ±0.1 mm Additional phantom and chamber plates for T29672 Reference number Product Detector type Dimensions Tolerance of plate thickness Measure H1 Measure H2 T29672/U2 RW3 plate for 1.0 cm³ chamber (rigid) 23331, (300 x 300 x 20) mm ±0.2 mm 7 mm 13 mm T29672/U3 RW3 plate for 0.3 cm³ chamber (rigid) 23332, (300 x 300 x 20) mm ±0.2 mm 7 mm 13 mm T29672/U4 RW3 plate for 0.1 cm³ chamber (flexible) 2332, (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm T29672/U5 RW3 plate for 0.3 cm³ chamber (flexible) , 31003, (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm T29672/U6 RW3 plate for cm³ chamber (flexible) , 31002, (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm T29672/U7 RW3 plate for 0.6 cm³ chamber (Farmer chamber) 23333, NE 2505, NE 2571 (300 x 300 x 20) mm ±0.2 mm 7 mm 13 mm D /07 en 25

26 Technical Manual - Technical Specifications Reference number Product Detector type Dimensions Tolerance of plate thickness Measure H1 Measure H2 T29672/U9 T29672/U10 RW3 plate for IC-10 ion chamber (thimble chamber) RW3 plate for Markus chamber and Advanced Markus chamber T29672/U12 RW3 plate for NA /493/494 (semiconductor probes) T29672/U13 T29672/U14 T29672/U15 RW3 plate for NACP electron chamber (parallel plate chamber) RW3 plate for soft X-ray chamber (0.02 cm³ soft X-ray chamber) RW3 plate for soft X-ray chamber (0.2 cm³ soft X-ray chamber) IC 10 (300 x 300 x 20) mm ±0.2 mm 7 mm 13 mm (300 x 300 x 20) mm ±0.2 mm 0.2 mm 19.8 mm NA /493/494 (300 x 300 x 20) mm ±0.2 mm 7 mm 13 mm NACP electron chamber (300 x 300 x 20) mm ±0.2 mm (300 x 300 x 20) mm ±0.2 mm 0.5 mm 19.5 mm (300 x 300 x 20) mm ±0.2 mm 0.5 mm 19.5 mm T29672/U16 RW3 plate for C ion chamber (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm T29672/U17 RW3 plate for detector 9111 (semiconductor probe) T29672/U19 RW3 plate for 0.6 cm³ chamber (Farmer chamber) 9111 (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm 30001, 30002, 30004, 30006, 30010, 30011, 30012, (300 x 300 x 20) mm ±0.2 mm 7 mm 13 mm T29672/U20 RW3 plate for Roos chamber (300 x 300 x 20) mm ±0.2 mm 1 mm 19 mm T29672/U21 RW3 plate for NE ion chamber (0.22 cm³ chamber) NE 2577 C (300 x 300 x 20) mm ±0.2 mm 7 mm 13 mm 26 D /07 en

27 Technical Manual - Technical Specifications Reference number Product Detector type Dimensions Tolerance of plate thickness Measure H1 Measure H2 T29672/U22 RW3 plate for Diamond detector (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm T29672/U23 T29672/U24 T29672/U25 T29672/U27 RW3 plate for PR06 ion chamber (thimble chamber 0.6 cm³) RW3 plate for PinPoint chamber (0.015 cm³) RW3 plate for cm³ chamber (NE chamber) RW3 plate for PinPoint 3D chamber (0.016 cm³) PR 06 (300 x 300 x 20) mm ±0.2 mm 10 mm 10 mm 31006, (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm NE 2561 (300 x 300 x 20) mm ±0.2 mm 7 mm 13 mm (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm T29672/U28 RW3 plate for PinPoint chamber (0.03 cm³) (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm T29672/U31 RW3 plate for Dosimetry Diode P (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm T29672/U33 RW3 plate for Semiflex 3D chamber (300 x 300 x 20) mm ±0.2 mm 5 mm 15 mm HINT The given dimensions for H1 and H2 refer to the reference point position of the detector in the plate (refer to the figures of the chamber plates). For ionization chambers, the measuring point shift must be taken into account where necessary. Parallel plate chambers like the Markus chamber must be irradiated only in the direction intended for it. There are a number of plates for other chambers or with several recesses available on request. D /07 en 27

28 Technical Manual - Technical Specifications Phantom plates of T Reference number Product Dimensions Tolerance of plate thickness T RW3 plate 400 x 400 x 1 mm (400 x 400 x 1) mm ±0.1 mm T RW3 plate 400 x 400 x 2 mm (400 x 400 x 2) mm ±0.1 mm T RW3 plate 400 x 400 x 5 mm (400 x 400 x 5) mm ±0.1 mm T RW3 plate 400 x 400 x 10 mm (400 x 400 x 10) mm ±0.1 mm Additional phantom and chamber plates for T Reference number Product Detector type Dimensions Tolerance of plate thickness Measure H1 Measure H2 T T T RW3 plate for soft X-ray chamber (0.02 cm³ soft X-ray chamber) RW3 plate for Markus chamber and Advanced Markus chamber RW3 plate for soft X-ray chamber (0.2 cm³ soft X-ray chamber) (400 x 400 x 20) mm ±0.2 mm 0.5 mm 19.5 mm 23343, (400 x 400 x 20) mm ±0.2 mm 0.4 mm 19.6 mm (400 x 400 x 20) mm ±0.2 mm 0.5 mm 19.5 mm T RW3 plate for 1.0 cm³ chamber (rigid) 23331, (400 x 400 x 20) mm ±0.2 mm 7 mm 13 mm T RW3 plate for 0.3 cm³ chamber (rigid) 23332, (400 x 400 x 20) mm ±0.2 mm 7 mm 13 mm T RW3 plate for 0.6 cm³ chamber (Farmer chamber) 23333, NE 2505, NE 2571 (400 x 400 x 20) mm ±0.2 mm 7 mm 13 mm T RW3 plate for C ion chamber (400 x 400 x 20) mm ±0.2 mm 5 mm 15 mm 28 D /07 en

29 Technical Manual - Technical Specifications Reference number Product Detector type Dimensions Tolerance of plate thickness Measure H1 Measure H2 T RW3 plate for 0.1 cm³ chamber (flexible) 2332, (400 x 400 x 20) mm ±0.2 mm 5 mm 15 mm T RW3 plate for 0.3 cm³ chamber (flexible) , 31003, (400 x 400 x 20) mm ±0.2 mm 5 mm 15 mm T RW3 plate for cm³ chamber (flexible) , 31002, (400 x 400 x 20) mm ±0.2 mm 5 mm 15 mm T RW3 plate for 0.6 cm³ chamber (Farmer chamber) (400 x 400 x 20) mm ±0.2 mm 7 mm 13 mm T RW3 plate for Roos chamber (400 x 400 x 20) mm ±0.2 mm 1 mm 19 mm T RW3 plate for NACP electron chamber NACP electron chamber (400 x 400 x 20) mm ±0.2 mm 5 mm 15 mm HINT The given dimensions for H1 and H2 refer to the reference point position of the detector in the plate (refer to the figures of the chamber plates). For ionization chambers, the measuring point shift must be taken into account where necessary. Parallel plate chambers like the Markus chamber must be irradiated only in the direction intended for it. There are a number of plates for other chambers or with several recesses available on request. D /07 en 29

30 Technical Manual - Technical Specifications Dimensions of the phantom Figure 7: Slab phantom (height in mm) Figure 8: Drawing of chamber plate for T29672 (dimensions in mm) 30 D /07 en

31 Technical Manual - Technical Specifications Figure 9: Drawing of chamber plate for T (dimensions in mm) D /07 en 31

32 Technical Manual - Technical Specifications 32 D /07 en

33 Service Manual - Cleaning Service Manual WARNING Improper execution of service tasks. Hazards to Persons! Equipment Damage! Ensure that the service tasks described below are only performed by specialized staff. In addition, ensure that all other service tasks are only performed by PTW-Freiburg or by a person authorized by PTW-Freiburg. 5 Cleaning General Information on Cleaning NOTICE To avoid surface damage, do not use disinfectants on a phenol base or peroxide compounds to disinfect the surface. The product cannot be sterilized or completely disinfected. The product must not be treated or come in contact with fat, oil, alcohol, or substances containing solvents. Cleaning agents and solvents contained in disinfectants (alcohols) have proved to be particularly harmful. Do not use cleaning agents that might attack polystyrene. D /07 en 33

34 Service Manual - Preventive Maintenance Clean the product simply by wiping it down with a dry or slightly moistened cloth. Use water or a mild soap solution. Alternatively, you can use a common disinfection agent for medical instruments which is specified in the list of disinfectants of your national hygiene institute (e.g., VAH in Germany). If your country does not provide such a list, we recommend either a solution on an aldehyde base or a solution with a quaternary ammonium compound. Phantom and Chamber Plates Clean the phantom and chamber plates as follows: Simply wipe the phantom and chamber plates down. Do not immerse the phantom and chamber plates in water or other liquids. 6 Preventive Maintenance Below, you will find a list of the maintenance measures and inspections necessary for the product. Check before each use Before each use, visually inspect the product for signs of mechanical damage. If damage or malfunctions are identified, the product must be repaired before it is used again. Repair Repairs may only be carried out by PTW-Freiburg or by persons/companies authorized by PTW- Freiburg. Calibration The exact calibration factor and supplementary data are included in the calibration certificate. It is recommended to have the product calibrated every 2 years at PTW-Freiburg or by specially trained staff on site. 34 D /07 en

35 Service Manual - Disposal of the Product 7 Storage 8 Disposal of the Product To maintain the planarity of the phantom and chamber plates the phantom must lie flat during storage, the plates must be stacked properly, the transport case must be used for storage if possible, the phantom and chamber plates must not be positioned vertically in any event, and sufficient time for temperature equalization must be allowed (see below). The typical lifetime of the product is approx. 10 years. At the end of the product lifetime, the components of the product must be disposed of in compliance with the applicable waste control regulations. The different materials must be separated and recycled as appropriate. The product does not contain hazardous materials. If the phantom was exposed to temperature changes, sufficient time must be allowed for the temperature in the phantom to adapt to the ambient temperature. It takes approx. 15 h for the temperature difference to drop to 20 % of the initial value (refer to Literature [3]). If no temperature equalization takes place, the temperature inside the phantom will be different from that at the edges, which will lead to an incorrect temperature correction of the measuring result. Furthermore, this difference in temperature may cause warping of the phantom plates. D /07 en 35

36 Literature Literature [1] Council Directive 93/42/EEC concerning medical devices (Medical Device Directive - MDD) [2] Council Directive 97/43/EURATOM on health protection of individuals against the dangers of ionizing radiation in relation to medical exposure [3] Tailor, R.C.; Chu, C.; Followill, D.S.; Hanson, W.F.: Equilibration of air temperature inside the thimble of a PTW- Farmer chamber, Med. Phys. 25 (1998), [14] Tello, V. M.; Tailor, R.; Hanson, W. F.: AAPM, 33rd Annual Meeting (1991), San Francisco, "Water equivalent" plastics for absolute dose calibration of photon and electron beam [15] Thwaites, D. I.: Phys. Med. Biol. 30(1), (1985), Measurements of ionisation in water, polystyrene and a "solid water" phantom material for electron beams [4] American Association of Physicists in Medicine (AAPM), Med. Phys. 10 (1983), 741 [5] Markus, B.: Strahlentherapie 116 (1961), 280 [6] Nordic Association of Clinical Physics (NACP), Acta Radiol. Oncol. 20 (1981), 401 [7] Bruinvis, I.A.D.; Heukelom, S.; Mijnheer, B. J.: Phys. Med. Biol. 30(10), (1985) Comparison of ionisation measurements in water and polystyrene for electron beam dosimetry [8] Constantinou, C.; Attix, F.H.; Paliwal, B. R.: Med. Phys. 9(3), (1982) A solid water phantom material for radiotherapy x-ray and gray beam calibrations [9] Galbraith, D.M.; Rawlinson, J.A.; Munro, P.: Med. Phys. 11 (1984), 197 [10] Harder, D.; Rubach, A.; Hermann, K.-P.; Überschär, A.: Medizinische Physik 1988 (Hrsg: F. Nüsslin) , Wasser- und gewebeäquivalente Festkörperphantome für hochenergetische Photonen und Elektronen [11] Randall, T. H.; Fraass, B. A.: Med. Phys. 14(3), (1987), Relative electron beam measurements: scaling depths in clear polystyrene to eqivalent depths in water [12] Reft, C. S.: Med. Phys. 16(2), (1989), Output calibration in solid water for high energy photon beams [13] Reinstein, L. E.; Pai, S.: Evaluation of a new white polystyrene phantom for radiation dosimetry 36 D /07 en

37 Index Index A Additional plates... 12, 25, 28 C Calibration Chamber plates Cleaning Components Correction factor... 16, 18 T Technical specifications Twin plate for Advanced Markus chamber Twin plate for Markus chamber Twin plate for Roos chamber D Dimensions of the phantom Disposal F Field inhomogeneity G General information... 2 I Intended use... 6 L List of figures... 5 Literature M Maintenance Measurement notes Measurements, general information P Phantom, setup Phantom plates... 11, 25, 28 R Repair RW3 for measurements "in water" S Safety information... 7 Symbols D /07 en 37