Research has been conducted on the concentration of radon gas in air quality in air-conditioned rooms that can increase the potential for lung cancer. Indoor air quality is influenced by factors such as room occupants, material buildings, equipment and furniture in the room, contamination of pollutants from the outdoor air, seasonal influences, lighting, temperature, humidity, indoor noise, and ventilation. In addition, indoor air quality can be affected by radon gas. The concentration of radon gas is relatively high compared to other natural radionuclides. It is estimated that around 55% of the radionuclide concentration in nature comes from radon gas and is the largest source of radiation received by the world population, which is around 1.3 mSv/year.

Research has been conducted on the effect of variations in X-ray tube voltage to value of Contrast to Noise Ratio (CNR) on CT Scan at Bali Mandara Hospital using a phantom as a patient replacement. This research aims to determine the effect of X-ray tube voltage to the CNR value. Exposure factors used are X-ray tube voltage with variations of 80, 110, 120 and 135 kV, constant X-ray tube current of 150 mA and constant exposure time of 1 s. The readings of Io, Ib, and sb values in phantom images were performed using RadiAnt DICOM Viewer software (64 bit) and analysis of the effect X-ray tube voltage on CNR values was determined by regression test. The results of the analysis show that the variation of the X-ray tube voltage has a significant effect on the CNR value, where the greater X-ray tube voltage, the greater the CNR value. When the X-ray tube voltage is adjusted to 135 kV, the optimal CNR values are 113.52 for air, 35.06 for derlin, 13.93 for acrylic, 10.44 for nylon and 12.19 for polypropylene.

Cancer was a disease caused of the abnormal growth of cells of body tissue turned to the cancer cells. For its development, these cancer cells can spread to other parts of the body, therefore, they can be the cause of the death. Cancer was a general term for all types of malignant tumors. It was one of the diseases required radiation therapy, namely breast cancer (mamma ca), wherein the breast cancer was the second type of cancer that causes of the death after cervical cancer for women. Radiotherapy was a cancer therapy used radiation sources at aiming to shrink and kill cancer cells as much as possible through the provision of the measured radiation doses on the tumor volume/target as well as to minimize the effects of the radiation on the healthy tissue around the tumor. The purpose of verification was to determine the suitability between the dose and time of irradiation of the radiation received by the patient with the radiation dose and irradiation time planned, thus, as not to experience a shortage or excess dosage and radiation irradiation time. The measurement of the dose and radiation irradiation time using constant Source to Surface Distance (SSD) techniques. The section handling the problem of the cancer therapy at Sanglah Hospital was in the Radiotherapy section of Radiology Installation. It was equipped with various medical support equipment, i.e, ISIS polling stations that conform to standard standards. The ideal dose criteria based on the isodoses curve was 95% minimal and 107% maximum about the target. The dose distribution was homogeneous. If the target dose has covered 100% then it can be stated that the plan was optimal. The verification of the dosage and time with ISIS TPS was in accordance with the Republic of Indonesia Minister of Health Regulation No.

It was researched on the application of Anoda Heel Effect (AHE) with a step wedge on the effect of Signal To Noise Ratio (SNR) on Computed Radiography (CR) has been carried out. This research was conducted on a 21 step wedge with two treatments, namely the application of AHE and without the application of AHE. This measurement is repeated three times on radiographs to obtain a total image of six images (without the application of AHE as many as three images and with the application of AHE as many as three images). The results of taking radiographs using AHE and without AHE were measured using the RadiAnt Dicom Viewer program. The SNR value on the step wedge image without the AHE application has an average of 26.89. The SNR value on the step wedge image using AHE is 60.54. The results of the correlation test (Pearson correlation test) on the SNR showed that there was a significant and very strong effect of the application of AHE on the step wedge on the SNR in CR (p-value <0.001 and the R-value ranging from 0.600 to 0.799).

Telah dilakukan penelitian analisis waktu pemupukan pada tanaman sawi hijau (Brassica rapa var. parachinensis)dengan teknik perunut radioaktif. Untuk menuju sistem pertanian berkelanjutan perlu adanya perbaikan pertanian(intensifikasi) selama beberapa tahun yang lalu masih signifikan, karena ketersediaan sumber daya alam danteknologi pertanian cukup memadai dan berimbang dengan ketersediaan lahan dan peningkatan jumlah penduduk.Keadaan ini sulit untuk dipertahankan dimasa yang akan datang, kecuali ada pendekatan baru yang menawarkan ide dan teknik untuk meningkatkan produktifitas pertanian. Efesiensi pemupukan tanaman dengan teknik perunut (tracer) radioisotop adalah salah satu potensi menujusistem pertanian berkelanjutan. Teknik perunut dapat digunakan antara lain untuk mempelajari hubungan antaratanah dan tanaman, menentukan kondisi optimal dalam penggunaan pupuk (waktu pemupukan, pola perakaranaktif tanaman, jenis dan takaran pupuk), mempelajari proses dekomposisi dan mineralisasi bahan organik, sertamempelajari proses fotosintesis tanaman,baik dengan metoda langsung maupun tidak langsung.Waktu pemupukanyang lebih tepat dapat ditentukan dengan teknik perunut tersebut, sehingga optimalisasi pemupukan dapat dicapai,tanpa pemborosan yang tidak berguna.Dari penelitian dengan menggunakan radioisotop P, ternyata waktupemupukan pada tanaman sawi hijau (Brassica rapa var. parachinensis) yang paling signifikan adalah padapukul 9.00 pagi. Waktu siang hari mulai pukul 11.00 sampai pukul 15.00 adalah waktu pemupukan yang sangatburuk. Sedangkan waktu sore hari yaitu pukul 15.00 sampai 17.00 menunjukkan waktu pemupukan yang semakinbaik namun tidak signifikan.32