Malaysian Journal of Analytical Sciences Vol 22 No 3 (2018): 446 - 451

DOI: 10.17576/mjas-2018-2203-10




VENTILATION EFFECT ON THE Radon-222 ANNUAL EFFECTIVE DOSE inSIDE Gua Gajah and Gua Penyu CAVES, Kompleks Gua Kota Gelanggi, Pahang, Malaysia


(Kesan Pengudaraan Kepada Dos Berkesan Tahunan Radon-222 dalam Gua Gajah dan Gua Penyu, Kompleks Gua Kota Gelanggi, Pahang, Malaysia)


Nazree Ahmad 1*, Junaidah Md Sani1,  Nur Hafilah Muslim1, Nur Amirah Alias1, Ahmad Saat 2


1Faculty of Applied Sciences

 Universiti Teknologi MARA Pahang, 26400 Bandar Tun Abdul Razak Jengka, Pahang, Malaysia

2Institute of Science,

Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia


*Corresponding author:



Received: 4 December 2016; Accepted: 1 December 2017




A study to determine the concentration and emanation rate of Radon-222 were done inside Gua Gajah and Gua Penyu limestone caves, Kompleks Gua Kota Gelanggi, Pahang, Malaysia to find the link between ventilation and annual effective dose. Gua Gajah has two major openings and features uneven earth surface unlike Gua Penyu which has single entrance and smooth passage way. Dosimeters with CR-39 solid state nuclear track detector (SSNTD) were distributed 15 m apart. For emanation rates, dosimeters were embedded about 5 cm into cave floor while for concentration measurements, they were placed 1 m above ground. The control samples were placed in front of the main entrance. The samples were left and collected after 30 days. Every CR-39 samples were etched with 6M NaOH solution with 70 ᵒC for 6 hours in water bath and observed under microscope of 200x linear magnifications to calculate tracks densities. Results indicated that the average Radon-222 emanation rate inside Gua Gajah was higher than that of Gua Penyu. On the other hand, the average concentration of Radon-222 inside Gua Gajah was lower than that of Gua Penyu. The average annual effective dose of Radon-222 in Gua Gajah and Gua Penyu was 0.084 mSv yr-1 and 0.12 mSv yr-1, respectively. These findings point out that ventilation contributed by cave openings plays an important role in reducing the indoor radon gas accumulation, thus lowering the annual effective dose.


Keywords:  emanation rate, radon gas, radon concentration



Kajian bagi mengukur  kepekatan dan kadar pemancaran Radon-222 telah dijalankan dalam  gua-gua batu kapur Gua Gajah and Gua Penyu, Kompleks Gua Kota Gelanggi, Pahang, Malaysia  untuk mencari hubungan di antara pengudaraan dengan dos berkesan tahunan. Gua Gajah dengan dua laluan utama menunjukkan mukabumi tidak sekata manakala Gua Penyu hanya mempunyai satu laluan masuk dan rata. Dosimeter dengan pengesan jejak nuklear keadaan pepejal CR-39 (SSNTD) diletakkan berjarak 15 m satu sama lain. Dosimeter untuk kadar pemancaran ditanam 5 cm ke dalam lantai gua manakala bagi pengukuran kepekatan, dosimeter  diletakkan 1 m di atas lantai gua. Sampel kawalan diletakkan di hadapan laluan masuk utama. Kesemua sampel ditinggalkan dan dikutip selepas 30 hari. Setiap sampel CR-39 kemudiannya dicelup dalam  rendaman panas larutan 6M NaOH  pada 70 ᵒC selama 6 jam sebelum dicerap di bawah microskop 200x pembesaran linear untuk menentukan kepadatan trek. Hasil menunjukkan purata kadar pemancaran Radon-222 dalam Gua Gajah lebih tinggi berbanding Gua Penyu. Sebaliknya, purata kepekatan Radon-222 dalam Gua Gajah lebih rendah berbanding Gua Penyu. Dos berkesan tahunan Radon-222 untuk Gua Gajah dan Gua Penyu masing-masing ialah 0.084 mSv yr-1 dan 0.12 mSv yr-1. Penemuan ini menunjukkan kesan pengudaraan daripada bukaan gua memainkan peranan penting dalam mengurangkan penumpukan radon gas dalaman seterusnya merendahkan nilai dos berkesan tahunan.


Kata kunci:  kadar pemancaran, gas radon, kepekatan radon



1.       Field, M. S. (2007). Risks to cavers and cave workers from exposures to low-level ionizing α radiation from 222Rn decay in caves. Journal of Cave and Karst Studies, 69(1): 207-228.

2.       Ahn, G. H. and Lee, J. K. (2005). Construction of an environmental radon monitoring system using CR-39 nuclear track detectors. Nuclear Engineering and Technology37(4): 395-400.

3.       Mohamed, A. E. (2012). An overview on studying 222Rn exhalation rates using passive technique solid-state nuclear track detectors. American Journal of Applied Sciences, 9(10): 1653-1659.

4.       Mansour, H. L., Tawfiq, N. F. and Karim, M. S. (2014). Indoor radon concentrations measurement in the dwellings of Thi-Qar governorate, Iraqi. Journal of Natural Sciences, 2(1): 19-26.

5.       Alkhalifa, I. M., and Bakr, H. (2007). Determination of radon exhalation rates in Basrah Governorate (Iraq) using CR-39 solid state nuclear track detector (SSNTD’s). Basrah Journal of Science (A), 25(2): 97-104.

6.       British Caving Association on Working Party (2012). Radon exposure during underground trips: A set of guidelines for caving and mining exploration. British caving association, Buxton.

7.       Kadhum, N. F., Jebur, L.A. and Ridha, A. A. (2016). Studying different etching methods using CR-39 nuclear track detector. Scientific Research, 4: 45-53.

8.       Farid, S. M. (2012). A study on the radon concentrations in Tobacco in Jeddah (Saudi Arabia) and the associated health effects. Medical Journal of Islamic World Academy of Sciences, 20(3): 84-93.

9.       Hussein, Z. A., Jaafar, M. S., and Ismail, A. H. (2013). Measurements of indoor Radon-222 concentration inside Iraqi Kurdistan: Case study in the summer season. Journal of Nuclear Medicine & Radiation Therapy, 4 (1):1-4.

10.    Ahmad, S., Zaini, H., Zaharidah, A. B., Zuraidah, A. M., Siti, M. S and Misbah, H. (2010). Some remarks on diurnal radon concentration at various locations in Peninsular Malaysia.  Journal of Nuclear and Related Technologies, 7(1): 49-57.

11.    Aljarallah, M. I. (2001). Radon exhalation from granite used in Saudi Arabia. Journal of Environmental Radioactivity, 53(1): 91-98.

12.    International Commission on Radiation Protection (1995). Protection against radon- 222 at home and at work. ICRP Publication, Pergamon, Oxford.


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