Quality Control Monitoring of Medical Diagnostic X-Ray Units in Southern Tanzania

Document Type : Original Paper


1 Southern Zone, Tanzania Atomic Energy Commission (TAEC), Mtwara, Tanzania

2 Eastern Zone, Tanzania Atomic Energy Commission (TAEC), Dar es salaam, Tanzania

3 Zanzibar Office, Tanzania Atomic Energy Commission (TAEC), Zanzibar, Tanzania.

4 Tanzania Atomic Energy Commission (TAEC) Headquarters, Arusha, Tanzania.


Introduction: The study focused on the assessment of quality control tests in X-ray units from the Southern regions of Tanzania to yield the data required to create and implement quality control policies and strategies.
Material and Methods: Quality control tests were conducted on twenty-six diagnostic X-ray units in private and government hospitals in southern regions of Tanzania during 2020 – 2021. The tests focused on the reproducibility of accelerating tube potential, time reproducibility, the accuracy of accelerating tube potential, half-value layer, beam alignment, and collimation. The statistical analyses were done by using the Microsoft Excel spreadsheet of 2013. The results were compared with the tolerance limits. 
Results: Of all X-ray units evaluated, 92.31% had kVp accuracy within the tolerance limit of 5% and 92% of the X-ray units had acceptable HVL values ≥ 2.3 mm Al at 80 kVp. Moreover, results have shown that 86.96% and 82.61% of X-ray units had acceptable beam collimation (≤ ±2 cm) and beam alignment (≤3% of the X-ray source and X-ray table), respectively.
Conclusion: Comprehensive regulatory inspections and equipment maintenance plans in the Southern zone is significantly required due to the high patient workload which attributes frequent breakdown of X-ray units. Moreover, radiographers need to be trained on how to minimize and detect beam misalignment and collimation failure since the most unacceptable results were observed from these tests.


Main Subjects

  1. United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and the effects of ionizing radiation. UNSCEAR 2008 report to the general assembly with scientific Annexes. United Nation vol. 1, United Nations Publication. New York; 2008.
  2. Ostensen H, Pettersson H, editors. The WHO manual of diagnostic imaging Radiographic anatomy and musculoskeletal system. Published by the World Health Organisation in collaboration with the International Society of Radiology. Malta; 2002.
  3. Murata CH, Fernandes DC, Lavínia NC, Caldas LV, Pires SR, Medeiros RB. The performance of a prototype device designed to evaluate general quality parameters of X-ray equipment. Radiation Physics and Chemistry. 2014;95:101-5.
  4. Ngoye WM, Motto JA, Muhogora WE. Quality control measures in Tanzania: is it done? Journal of Medical Imaging and Radiation Sciences. 2015;46(3):23-30.
  5. AL-Jasim AK, Hulugalle SN, Al-Hamadani HK. A quality control test for general x-ray machine. World Scientific News. 2017; 90:11-30.
  6. Begum M, Mollah AS, Zaman MA, Rahman AKMM. Quality control tests in some diagnostic X-ray units in Bangladesh. Bangladesh J. Med. Sci. 2011;4(1):59-66.
  7. Sungita YY, Mdoe SSL, Msaki P. Diagnostic X-ray facilities as per quality control performances in Tanzania. J. Appl. Clin. Med. Phys. 2006;7(4):66-73.
  8. Ebisawa MLN, Magon MFA, Mascarenhas YM. Evolution of X-ray machine quality control acceptance indices. J. Appl. Clin. Med. Phys. 2009;10(4):252-9.
  9. Nkuba LL, Nyanda PB. Compliance and quality control monitoring of diagnostic X-ray facilities in Dar es Salaam city, Tanzania. Braz. J. Rad. Sci. 2017;5(2):1-17.
  10. Korir GK, Wambani JS, Ochieng BOM. Optimization of the Radiological Protection of Patients in Diagnostic Radiology Department at Kenyatta National Hospital in Kenya, Phase I. The Second All African IRPA Regional Radiation Congress; 2007; 167-76.
  11. Cherry P, Duxbury AM. Practical radiotherapy physic and equipment. 2nd ed. West Sussex: Chichester; 2009.
  12. Cember H, Johnson TE. Introduction to health physics. 4th ed. New York; 2009.
  13. Hashemi M, Bayani Sh, Shahedi F, Momennezhad M, Zare H, Gholamhosseinian H. Quality assessment of conventional X-ray diagnostic equipment by measuring X-ray exposure and tube output parameters in Great Khorasan Province, Iran. Iran J Med Phys. 2019;16(1):34-40.
  14. International Commission on Radiological Protection (ICRP). ICRP Publication 60: 1990 Recommendations of the International Commission on Radiological Protection. 1991.
  15. International Commission on Radiological Protection (ICRP). ICRP Publication 75: General principles for the radiation protection of workers. 1997.
  16. Yallambie PB, Chilton JC. ICRP Publication 103: The 2007 recommendations of the international commission on radiological protection. Annals of the ICRP publication 103. Ottawa: International Commission on Radiological Protection (ICRP). Valentin; 2007.
  17. The united republic of Tanzania Act No. 7 of 2003 An act to establish Tanzania Atomic Energy Commission and provide for its functions in relation to the control of the use of ionizing and non-ionizing radiation sources, the promotion of safe and peaceful uses of atomic energy and nuclear technology, and to repeal the protection from Radiation Act. 1983.
  18. Poznanski AK, Fischer HW, Gray JE, Hendee WR, Kereiakes JG, Kundel HL, et al. Quality assurance for diagnostic imaging. NCRP report number 099. Washington; 1988.
  19. Chu RL, Fisher J, Archer BR, Conway BJ, Goodsitt MM, Glaze S, et al. Standardized methods for measuring diagnostic X-ray exposures. AAPM report number 31, Med Phys. New York; 2005.
  20. Suleiman SA, Salum SK, Ebenezer K. Quality control assessment of diagnostic X-ray unit in Zanzibar, Tanzania. Phys. Sci. Int. J. 2020;24(12):1-9.
  21. Ismail HA, Omer MA, Ali AO, Garelnabi ME, Mustapha NS. Evaluation of diagnostic radiology department in term of quality control (QC) of X-ray units at Khartoum State Hospitals. Int. J. Sci. Res. 2015;4(1):1875-8.
  22. Jomehzadeh Z, Jomehzadeh A, Tavakoli MB. Quality control assessment of radiological devices in Kerman Province, Iran. Iran J Med Phys. 2016;13(1):25-35.
  23. Rasuli B, Pashazadeh AM, Tahmasebi Birgani MJ, Ghorbani M, Naserpour M, Fatahi-Asl J. Quality control of conventional radiology devices in selected hospitals of Khuzestan province, Iran J Med Phys. 2015;12(1):101-8.
  24. Shepard SJ, Lin PP, Boone JM, Cody DD, Fisher JR, Frey GD, et al. Quality control in diagnostic radiology. AAPM report number 74. Med Phys. Wisconsin; 2002.
  25. Asadinezhad M, Toossi MTB, Ebrahiminia A, Giahi M. Quality Control Assessment of Conventional Radiology Devices in Iran. Iran J Med Phys. 2017;14(1):1-7.
  26. International Commission on Radiological Protection. Protection of the patient in diagnostic radiology. ICRP Publication 34. New York; 1982.
  27. Meechai T, Chousangsuntorn K, Owasirikul W, Mongkolsuk M, Lampa W. Comparison of testing of collimator and beam alignment, focal spot size with slit camera, and tube current consistency using computed radiography and conventional screen-film systems. J Appl Clin Med Phys. 2019;20(6):160-9.
  28. Akpochafor MO, Omojola AD, Soyebi KO, Adeneye SO, Aweda MA, Ajay HB. Assessment of peak kilovoltage accuracy in ten selected X-ray centres in Lagos metropolis, South-Western Nigeria: A quality control test to determine energy output accuracy of an X-ray generator. J. Health Res Rev. 2016;3(2):60-5.
  29. Lacerda MAS, Silva TA, Oliveira AH. The methodology for evaluating half-value layer and its influence on the diagnostic radiology. Radiol Bras. 2007;40(5):331-6.
  30. Jang D, Kim S. Performance Evaluation of Diagnostic X-Ray Equipment Regarding the Hospital Size in the Republic of Korea, Iran J Med Phys. 2019;16(3):195-9.
  31. Akpochafor MO, Adenye SO, Daniel AF, Omojola AD, Aweda AM. Evaluation of kilovoltage failure in conventional X-ray machines among selected X-ray Centers in Jos North Local government area of Plateau State, Nigeria. Nig. Qt J. Hosp. Med. 2017; 27(2): 768 –
  32. International Atomic Energy Agency. Optimization of the radiological protection of patients undergoing radiography, fluoroscopy and computed tomography. Final report of a coordinated research project in Africa, Asia and Eastern Europe. Vienna; 2004.
  33. Dahinde PS, Dapke GP, Raut SD, Bhosale RR, Pawar PP. Analysis of half value layer (HVL) tenth value layer (TVL) and mean free path (MFP) of some oxides in the energy range of 122 KeV to 1330 KeV. Indian J. Sci. Res. 2019;9(2):79-84.
  34. Aziz ROA. Establishment of standard X-ray qualities to be used in diagnostic level at SSLDS. MSc thesis, University of Khartoum. 2007.
  35. Hendee WR, Rossi RP. Quality assurance for radiographic X-ray units and associated equipment. United State food and drugs administration publication 79.8094. Colorado; 1979.
Volume 20, Issue 1
January and February 2023
Pages 53-61
  • Receive Date: 28 December 2021
  • Revise Date: 08 May 2022
  • Accept Date: 14 May 2022
  • First Publish Date: 14 May 2022