SOAL – SOAL TERKAIT PENGAWASAN PEMANFAATAN RADIOTERAPI

Beberapa waktu yang lampau sudah disajikan “Soal-soal X-ray Beam Properties”, pada kesempatan berikut ini “Soal-soal Terkait Pengawasan Pemanfaatan Radioterapi” yang secara khusus ditujukan bagi kawan-kawan Inspektur Keselamatan Nuklir Bapeten, khususnya Inspektur Kesehatan dan Industri. Namun Pihak lain yang terkait pemanfaatan layanan radioterapi, misalnya Praktisi Medik (Radiografer Terapi/Radioterapis dan Fisikawan Medik), PPR Medik Tingkat I dan adik-adik mahasiswa (Fisika Medik FMIPA UI dan D4 Radioterapi Poltekkes Kemkes) juga dapat melatih kemampuan akademisnya.

Untuk dapat menjawab soal-soal ini, sebaiknya dibaca terlebih dahulu beberapa referensi diantaranya, (1) IAEA, International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources”, Safety Series No. 115, Vienna (1996); (2) IAEA-TECDOC-1067, Organisation and implementation of a national regulatory infrastructure governing protection against ionising radiation and the safety of radiation sources, Vienna (1999); (3) IAEA-TECDOC No. XXX, Radiation Safety in Radiotherapy, Vienna (2000); (4) IAEA-TECDOC No. 1040, Design and Implementation of a Radiotherapy Programme: Clinical, Medical Physics, Radiation Protection and Safety Aspects, Vienna (1988); (5) IAEA, Safety Report Series, Radiation Protection in the Design of Radiotherapy Facilities, Vienna (2006); dan (6) Togap Marpaung “Memahami Basic Safety Standard-BSS No.15 Tahun 1996”, Bapeten, Jakarta (2003), materi tulisan BSS ada dalam blog ini.

Soal-soal ini diperoleh ketika mengikuti IAEA Regional Training Course on Authorization and Inspection of Radiation Sources in Radiotherapy di Manila, Philippines 14 – 25 November 2005. Selamat Mengasah Otak dan Semoga Bermanfaat!

IAEA REGIONAL TRAINING COURSE ON AUTHORIZATION AND INSPECTION OF RADIATION SOURCES IN RADIOTHERAPY

Manila, Philippines 14 – 25 November 2005

EVALUATION TEST

PART 1: Course on Organization and implementation of a Natioal Regulatory Programme for the Control of Radiation Sources

NAME: ----------------------------------------------------------------------------------

COUNTRY:  ----------------------------------------------------------------------------

Instructions: This is a multiple choice type of evaluation test

                      Encircle the best answer among the choices given after each question or

                      as specifically directed.

1.  Mark the statement which is not a disavantage of a prescriptive regulation

a.   its routine use can lead to a “compliance culture” instead of a “safety culture”.

b.   its preparition can be difficult and requires considerable practice, specific knowledge and experience.

c.   it is easily applicable to a specific practice.

d.   its reviewing and amending is necessasry to keep pace with changes in technology.

2.  Guidance levels for medical exposure shall be established for use by medical practitioners. The guidance levels are not intended:

a.  to be a reasonable indication of doses for average sized patients.

b.  to provide guidance on what is achievable with current good practice rather than on what should be considered optimum performance.

c.  to limit or to constrain higher exposures if these are indicated by sound clinical judgement.

d.  to be revised as technology and techniques inmprove.

3.  Exemption should not be granted to permit practices that would otherwise not be:

a.  optimized.

b.  justified.

c.  notified.

d.  ALARA.

4.   Read very carefully the following criteria. Two from the criteria laid down can not be considered as criteria for exemption of practices and sources within practices without further consideration from the requirements of the BSS.

a.   the expected effective dose incurred to any user due to the practice or source is in the order of 10 µSv per year and the collective dose committed by one year of performance of the practice is no more than about 1 person Sv.

b.   the expected effective dose incurred to any member of the public due to the practice or source is in the order of 10 µSv per year and the collective effective dose committed by one year of performance of the practice is no more than about 1 person Sv.

c.   the expected effective dose incurred to any member of the public due to the practice or source is in the order of 10 µSv per year and an assessment for the optimisation of protection shows that exemption is the optimum option.

d.   the expected effective dose occured to any member of the public due to the practice or source may exceed 10 µSv per year but the collective dose committed by one year of performance of the practice is no more than about 1 person Sv. 

5.  Read carefully following statements related to clearance levels. Only one of them  is with the BSS.

a.   clearance levels shall  not be approved by the Regulatory Authority.

b.   clearance levels ≥   exemption levels.

c.   clearance levels  ≤  exemption levels.

d.   for bulk amounts of materials, clearance > > exemption levels.

6.  Mark the unreasonable criteria:

The Regulatory Authority is reviewing an application for a temporary change in dose limitation. Such change shall be  approved only exceptionally and for a limited period of time, if the Regulatory Authority determines that:

a.   special circumtances exist which require such temporary change.

b.   visitors be accompanied in the specific working area by a person  knowledgeable about the protection and safety measures.

c.   the practice is still justified and radition safety is optised.

d.   workers involved have been consulted and their agreement was obtained.   

7.  Which one of following devices should be subject to licensing?

a.   Mammography X-ray equipment.

b.   Linear accelerator.

c.   a set of calibration sources for educational use.

d.   LDR brachyterapy equipment.

8.  The basic purpose of a regulatory system for practices with radiation sources is

a.   to balance benefits and detriments of the use of radiation sources for individuals and society.

b.   to eliminate possible harmful effects of radiation to exposed workers, patients’ public and enverinment.

c.   to prevent the occurrence of deterministic effects and to minimize the stochastic effects.

d.   to tensure full safety in the use of radiation sources in medical, industrial, agriculture, research and other practices.

9.  Primary responsibility for radiation safety is held by

a.   designated Radiation Protection Officer as an individual competent in radiation protection matters relevant for the practice.

b.  any exposed worker as part his duty to follow applicable rules and procedures for protection and safety.

c.  Regulatory Authority established by national legislation.

d.  licensees and/or employers.

10. For medical exposure, dose limits are not applied

a.  at all.

b.  for patients only.

c.  for patients in radiotherapy.

d.  for patients and persons voluntary helping in the support and comport of patients.

11. Pregnancy is not a reason to exclude a female worker from work, but

a.  working conditions of pregnant female worker should be appropriately adopted.

b.  pregnant female worker is not allowed to work in cotrolled areas.

c.  pregnant female worker is not allowed to work with unsealed sources.

d.  pregnant female worker should be temporarily moved to other type of work without radiation risk.

12. Worker occupationally exposed to effective dose higher than 50 milisievert (mSv) shall not with radiation souces

a.  at least until the end of the year.

b.  for ever.

c.  until his fitness for such work is recognized as a result of health surveillance.

d.  until report of the event is accepted by the Regulatory Body.

13. Exposures grater than a dose limit shall be communicated to the regulatory  Authority

a.  as soon as possible .

b.  monthly or in the case of  accidents immediately.

c.  after investigation of the event an a written report on its cause and with recommendations for preventing the recurrence.

d.  as a part of the regular annual radiation safety report only.

14. Qualified experts are

a.  the most experienced and competent workers capable to advise others to perform their work safely.

b.  individuals recognized as having expertise in a relevant field of specialization.

c.  Radiation Protection Officers.

d.  designated by the registration or licensee and approved by the regulatory authority.

15. Clearance levels are activity concentration and/or total values used

a.  for evaluation of proper decontamination of the workplace.

b.  in releasing radioactive material from regulatory control.

c.  as maximum activity for patients in therapy on discharge from hospitals.

d.  as un upper value in the dose optimization process.

16. Which of the following applications using radioactive sources would notification be sufficient for purposes of regulatory control?

a.  Industrial radiography using Ir-192.

b.  nuclear medicine using I-131.

c.  commercial sale of references check sources.

d.  teletherapy facility using Co-60.

17. Graded enforcement means

a.  action taken by the regulatory authority for non compliance of the licensees to regulatory requirements.

b.  enforcement action is based on the nature of non compliance and implications to safety.

c.  imposition of maximum penalty for repeated non compliances.

d.  issuance of suspension order until corrective actions are implemented by the licences.

18. The regulatory authority must have the following powers and responsibilities clearly defined in the law, EXCEPT.

a.  standard setting and rule making powers.

b.  inspections of licensee’s facility and enforcement of the regulatory requirements, including the conduct of unannounced inspection.

c.  grant of exemptions from regulatory requirements based on a set of criteria and establishment of clearence levels for radioactive waste.

d.  setting up guidance levels for medical diagnosis using radiation source.

19. To implement the role and functions of the regulatory authority in the national emergency plan, which of the following is required

a.  appropriate trained manpower.

b.  equipment and facilities.

c.  logistic support and funding.

d.  all of the above.

20. Emergency exercises are necessary for the following purposes, EXCEPT:

a.  to assess the effectiveness and adequacy of the emergency plan and procedures.

b.  to ensure that emergency response capabilities remain effective.

c.  to generate more resources for the intervening organization for the maintenance of the emergency plan.

d.  to provide information which can be used as a basis for the modification and/or revision of the emergency plan.

Instruction: In questions 21-25, encircle the letter of the incorrect anwer

21. The following essential technical services should be available to the regulatory authority

a.  dosimetry services

b.  calibration services.

c.  analitycal services.

d.  accreditation for services.

e.  academic program in regulation.

22. Staffing levels will depend on:

a.   the size, scope and complexity of practices.

b.   the nature of the regulation (prescriptive/performance).

c.   the country geographical condition.

d.   the extend to which practice specific guidance documents and standard assesments plans used.

e.   the status of the regulatory program i.e. organization, implementatiaon, or operational phase.

23. The purpose of monitoring external and internal doses is to:

a.   provide security and confidence in safety procedures.

b.   provide legal evidence.

c.   identify poor working practise.

d.   identify personnel changes in working conditions.

e.   exercise control over individual dose.

24. Hiring of consultans by regulatory authority is governed by the following politics:

a.   consultans should be effectively independent of the operator.

b.   the use consultants shall not relieve the regulatory authority of any of its responsibilities.

c.   the regulatory authority’s responsibility for making dicisions and recomendations may be delegated to the consultant, subject to the country’s regulations.

25. The regulatory authority should be empowered to:

a.   develop safety pricinciples and criteria.

b.   establish regulations and issue guidance documents and advice.

c.   require operators to conduct safety assesments on behalf of the regulator.

d.   issue, amend, suspend and revoke authorizations.

SOAL-SOAL X-RAY BEAM PROPERTIES

Yth: Bapak/Ibu/Sdr/Sdri
Masih ingatkah tulisan dalam Blog ini mengenai “Perjalanan Hidup Dalam Dunia Radiasi” yang mengulas awal kehidupan memasuki “medan radiasi” melalui pendidikan di APRO dengan nama panggilan “TUBE”. Pada kesempatan ini, dengan segala hormat perkenankanlah “Mr Tube” menyajikan 57 (limapuluh tujuh) soal terkait sinar-X yang diperoleh ketika mengikuti pendidikan program Post Graduate Diploma in Radiation Protection di Universiti Kebangsaan Malaysia. Soal-soal ini secara khusus didedikasikan kepada Adek-adekku Mahasiswa Jurusan Fisika Medik, Poltekkes Jurusan Teknik Radiodiagnostik dan Radioterapi atau ATRO, dan Poltekkes Jurusan Teknik Elektromedik atau ATEM.

Namun, bagi para penyelenggara pelatihan Petugas Proteksi Radiasi (PPR) Medik Tingkat I dan Tingkat II serta PPR Industri Tingkat I, (khususnya yang bekerja di bidang Radiografi Industri) juga dapat menggunakan soal-soal ini untuk mengukur tingkat pemahaman peserta pelatihan mengenai “X-ray Beam Properties”. Sebagaimana diketahui bahwa pesawat sinar-X adalah objek hukum yang diatur dalam Peraturan Perundang-undangan Ketenaganukliran sebagai tenaga nuklir yang merupakan sumber radiasi. Dengan demikian masalah penerapan proteksi radiasi terkait keselamatan pasien dan mutu citra (foto rontgen) sangat ditentukan oleh pemahaman X-ray Beam Properties secara baik. Dapat disimpulkan bahwa persoalan yang sangat mendasar yang harus diketahui oleh PPR adalah X-ray Beam Properties.

Untuk menjawab pertanyaan soal-soal berikut ini dan memahami lebih mendalam terkait permasalahan dan penerapan dalam bidang medik, dianjurkan membaca referensi, antara lain “Physical Principles of Medical Imaging”, Second Edition, oleh Perry Spruwls, Jr, Aspen Publishers, Inc, USA, 1995. 

Sebenarnya "Mr Tube" masih memiliki sekitar 25 (duapuluh lima) soal lagi dalam bentuk True or False, yang cukup menarik untuk dibahas. Sayangnya, soal-soal tersebut belum ditemukan. Mohon maklum sistem dokumentasi belum baik, selain itu pernah pindah gedung kantor 4 (empat) kali yang tentunya dalam instansi yang sama Bapeten. 

Semoga bermanfaat!

X-RAY BEAM PROPERTIES

Prepared by Togap P Marpaung

1. The factor which is a measure of the number of electrons striking the X –ray tube anode per second is:
1. kilovoltage
2. miliampere
3. filament current
4. peak voltage
5. filament voltage
2. The factor which determines the potential difference between the filament and the anode of an X-ray is the:
1. mA
2. mAs
3. filament current
4. filament voltage
5. kVp.
3. Characteristic photons from the target of an X-ray tube are characteristic of the:
1. incident electron energy
2. incident photon energy
3. kVp
4. target material
5. mA
4. The potential energy lost by an electron when it moves closer to the nucleus of atom:
1. is converted into additional kinetic energy of the electron
2. causes the nucleus of the atom split
3. is transferred to the nucleus
4. results in the formation of a neutron
5. is given off as a photon.
5. Bremsstrahlung refers to:
1. the continuous spectrum of photons is emitted by an X-ray tube
2. the energy of a photon emitted by an X-ray tube
3. the energy of a proton
4. charged particles
5. c, and d above.

Download Soal-Soal Lengkap di sini!!!

RADIATION SAFETY IN USE OF INDUSTRIAL RADIOGRAPHY

Gamma radiography is an important tool in non - destructive testing (NDT) on construction sites and remote locations. Main applications are weld inspection on oil and gas pipelines, power plants and as well as in chemical and petrochemical production sites. Gamma radiography is a very economical and at the same time safe process to ensure operational safety of inspected assemblies resulting in better protection of human health and environment. Gamma radiography completes the full range of modern NDT applications. Where other methods are not possible due to lack of electricity in the field, gamma radiography can full fill this requirement. Easy positioning of the very small focus spot and short preparation time are also advantages of the use of radionuclide in NDT.

The most common radionuclide used in industrial radiography are Co-60, Ir-192, Se-75 and Yt-169. On account of the hard energy range the use of Co-60 is limited to a big wall thickness of steel and concrete up to 150 mm. For less thickness material the use of other mentioned radionuclide are more suitable.

Download Tulisan ini secara lengkap di sini !!

KABEL PENUNTUN SUMBER KAMERA RADIOGRAFI INDUSTRI

1. Umum

Source guide tubes are flexible stainless steel tubes with a protective polyvinyl covering. Intermediate and termination source guide tubes are available which are interconnectable to provide the required length. The intermediate section tube has a male connector at one end and a female connector at the other and can be used with a disconnectable source stop as a guide tube termination. The maximum standard length, with extension(s), is 21 feet. Longer and custom designed guide tubes might require government authorization.

2. Persyaratan Inspeksi dan Perawatan

2.1. Persyaratan Inspeksi

Daily inspection of the source guide tube(s)

a)    Remove the protective covers from the swaged fittings on the source guide tubes. Inspect both swage fittings to ensure the threads are not stripped or clogged with dirt, grease or sludge. Inspect the ears on the bayonet fitting to ensure they are not bent, broken or excessively worn.

b)   Inspect each length of source guide tube that will be used for cuts, inward dents and heat damage. The inspection is primarily by visual inspection, but it should include by using  hands to feel for the inward dents.

c)    Inspect the attachment of the collimator to the source stop (exposure head) if used during radiography.

2.2. Persyaratan Perawatan

Persyaratan Perawatan Rutin

Clean and inspect the source guide tubes in accordance to the complete service section. Record the results of the inspection and any repairs that are performed. All source guide tubes found to be deficient during this inspection must be removed from service and sent to a service center for repairs. Deficient components must be tagged with a status indicator to prevent inadvertent use.

3. Prosedur Inspeksi dan Perawatan

3.1. Prosedur Inspeksi

3.1.1. Pemeriksaan Visual

a)    Check each length of guide tube that will be used for cuts, inward dents and Heat damage.

b)   Check the threads on all couplings for damages.

c)    Check the tubs for dents or crushing

3.1.2. Inspeksi Fisik

a)   Inspect guide tube length, The standard length is 7  feet of each .set of 3 tubes is 21 feet

b)   Check for binding by holding the tube vertical and dropping a dummy source though.

3.2. Prosedur Perawatan

3.2.1. Perawatan Rutin

    Maintenance procedure should be performed at 3 months intervals by radiographer

a)    Clean, inspect and maintenance the drive cable.

b)   Clean and inspect the source guide tube.

c)    Clean and inspect the projector for wear or obvious damage.

d)   See that radioisotope warming labels secure and legible, Don’t cover with any other labels

e)    Check that this source out it shipping plug is place and that crew and nut turn freely, but are not loose.

f)    Check for wear in the cable connector using the NO-Go gauge. There are four NO-GO tests-ball diameter; ball shank ;slot width; and connector gap width

g)   Check that the selector ring and lock mechanism operate freely

3.2.2. Perawatan Lengkap

a)    Inspect each length of source guide tube that will be used for cuts, inward dents and heat damage.

b)   Check the threads on all couplings for damage.

c)    Check the tubes for dents or crushing

d)   The tube may clean by running a degreaser soaked swab, attached to the end of a drive cable, and thought them. Repeat until the swab emerges clean; make sure that no bits of swab are left inside the terminal tube.

e)    Check for binding by holding the tube vertical and dropping a dummy source though.

Referensi

1. Standard Specification for Apparatus for Gamma Radiography, International Standard (ISO 3999-1977).
2. Operation and Maintenance Manual for Sentitel 880  Series  Source Projector, Sentitil Company.
3. Operation and Maintenance Manual for Model 660 Gamma Ray  Projector, Tech/OSP inc.

KAMERA RADIOGRAFI INDUSTRI PORTABEL

KATA PENGANTAR       

Dalam kesempatan ini, disajikan 7 (tujuh) tulisan mengenai Kamera Radiografi Industri yang membahas berbagai hal yang saling terkait, sebagai berikut:

1. Kamera Radiografi Industri Portabel;
2. Kabel Penuntun Sumber;
3. Radiation Safety in Use of Industrial Radiography;
4. Penyebab Terjadinya Kecelakaan Radiasi dalam Penggunaan Kamera Radiografi Industri;
5. Pengalaman Tak Terlupakan Inspeksi di Fasilitas Radiografi Industri Kanada;
6. Pelajaran Berharga Mengikuti Seminar Pelatihan Inspektur di Kanada; dan
7. Belajar Studi Kasus Kecelakaan Radiasi di Universiti Kebangsaan Malaysia.

Materi tulisan ini juga sekaligus menjawab pertanyaan dari pengunjung Blog mengenai ”menentukan ketepatan posisi sumber macet pada kabel penuntun sumber”. Mohon maaf atas keterlambatan tanggapan kami.

Meskipun pernah terlibat dalam beberapa kegiatan yang terkait dengan kondisi dan permasalahan kamera radiografi di tanah air, kemurnian tulisan ini sedapat mungkin dijaga agar tidak memasuki ”wilayah kebijakan” sehingga tidak memberikan suatu penilaian yang dapat berdampak kurang baik. Memang ada sedikit yang dikaitkan, hal itu hanya suatu keinginan berupa saran yang ditinjau dari aspek keselamatan radiasi, misalnya adanya ketentuan setiap kamera radiografi industri wajib diuji paling kurang sekali dalam setahun dalam rangka perpanjangan izin penggunaan.

Adapun beberapa kegiatan yang pernah dilakukan terkait dengan kondisi dan permasalahan kamera radiografi di tanah air, diantaranya:

1. melakukan inspeksi; 
2. melakukan kajian keselamatan radiasi;
3. mengajar pelatihan Petugas Proteksi Radiasi di Bidang Industri;
4. menjadi narasumber pada kegiatan Asosiasi Perusahaan Inspeksi Indonesia (Apitindo), dan kegiatan seminar nasional yang diselenggarakan oleh Dewan Keselamatan dan Kesehatan Kerja Nasional (DK3N), Kementerian Tenaga Kerja RI; dan
5. menjadi koordinator penyusunan Peraturan Kepala Bapeten tentang Keselamatan Radiasi dalam Penggunaan Peralatan Radiografi Industri.

Suatu saat nanti direncanakan agar dapat menulis ”Potret Pemanfaatan Kamera Radiografi Industri di Tanah Air” dari sudut pandang Inspektur Utama Keselamatan Nuklir Bapeten dalam rangka berbagi pengalaman.  Semoga Bermanfaat!

  
1. Komponen Utama
Kamera radiografi industri portabel dan peralatan penunjang (perlengkapan), terdiri dari 4 (empat) komponen utama, meliputi:

1. Pemasangan Sumber Radioaktif (SourceAssembly);
2. Peralatan Kamera Radiografi Portabel (Portable Exposure Device);
3. Kendali Kabel Pendorong (Drive Cable Control); dan
4. Kabel Penuntun Sumber (Source Guide Tube).

1.1. Pemasangan Sumber Radioaktif (SourceAssembly)

Gambar 1. Pemasangan sumber radioaktif

1.2. Peralatan Kamera Radiografi Portabel (Portable Exposure Device)

Gambar 2. Kamera Radiografi Portabel

1.3. Kendali Kabel Pendorong (Drive Cable Control)

Gambar 3.   Kendali Kabel Pendorong dengan Odometer

Gambar 4.  Kendali Kabel Pendorong  tanpa Odometer

1.4. Kabel Penuntun Sumber (Source Guide Tube)

Gambar 5. Source Guide Tube

 

2. Sistem Operasi Kamera Gamma

Sistem operasi kamera radiografi industri dikelompokkan dalam 2 (dua) kategori, yaitu: Kategori I dan Kategori II.  

Kategori I

The source is not removed from the exposure container for an exposure. The beam of radiation is exposed by opening the shutter or by moving the sealed source within the device, or by other meaning (source is stored at the center of a block of shielding material. A portion of the shielding can be removed, or the shielding or source is moved to expose the source. The solid angle of the useful beam is not usually more than 60°. The container usually limits the beam dimensions, but additional collimation may be used to limit the beam further to the minimum size necessary for radiography. The movement is controlled either directly or by remote means.)

Gambar 6. Kategori I

Kategori II

The source assembly is mechanically projected out of the container and travels along a guide tube projection sheath to the exposure head. The projection is hand or motor driven by the radiographer. A cable usually moves the source assembly. Systems that rely on negative air pressures or gravity to return the source to the shielded position may not be designed to fail safe, and hence some Regulatory Authorities will not authorize the use of such systems. Projection systems enable the radiographer to operate the system at a safe distance from the source. The end of the guide tube is placed in a collimator locating the source in the desired position and limiting the beam to the minimum size necessary for the task.

Gambar 7. Kategori II

3. Inspeksi Harian Kendali Kabel Pendorong

Inspeksi harian terhadap Kendali Kabel Pendorong harus dilakukan setiap hari dengan menggunakan peralatan Go No Gauge Tests, sebagaimana pada Gambar 8.

Gambar 8. NO GO Gauge Tests

4. Inspeksi Pengoperasian

Untuk menjamin kinerja kamera radiografi industri dalam keadaan siap digunakan harus dilakukan Uji Operasi Penuh (Full Operation Test), dengan cara sebagai berikut:

Run though the normal operating sequence several times, using the test connector or a dummy source assembly (non radioactive), to ensure smooth operation by setting equipment, sebagaimana pada Gambar 9.

Gambar 9.Uji Operasi Penuh

Referensi

1. IAEA, Radiation Protection and Safety in Industrial Radiography, Safety Reports Series No.13, IAEA, Vienna (1999).
2. Standard Specification for Apparatus for Gamma Radiography, International Standard ISO 3999-1977)
3. Operation and Maintenance Manual for Sentitel 880 Series Source Projector, Sentitil Company
4. Operation and Maintenance Manual for Model 660 Gamma Ray Projector, Tech/OSP inc
5. Guide for the Preparation of Applications for the Use of Sealed Sources and Devices for Performing Industrial Radiography, U.S. Nuclear Regulatory Commission, 1984.