• Journal of Radiation Protection and Research
• /
• v.20 no.2
• /
• pp.129-136
• /
• 1995

In spite of the prescriptions on the reference X-ray fields given by the International Organization of Strandard(ISO) and American National Standard Institute(ANSI), the measurement of X-ray spectrum is not only time consuming but very difficult, paticularly when significant corrections have to be applied to the measured pulse-height distributions of the observed spectra. This paper describes the calculation method of ISO Narrow Series and ANSI X-ray filtered radiations by theoretical model which is modified framer's theory by target attenuation and backscatter correction. The X-ray spectra, average energies and conversion coefficients are calculated and compared with those obtained using the spectra prescribed by ISO and AMSI to assure good agreement.

• Journal of Radiation Protection and Research
• /
• v.23 no.3
• /
• pp.159-174
• /
• 1998

Personal dosimetry system is required to measure the personal dose equivalent accurately in a wide range of radiation fields, but the dose evaluation algorithms have been developed with the X-ray fields described in MOST Ordinance (equivalent to the ANSI N13.11) from which the actual fields to be monitored may be significantly different. To evaluate the dose more accurately when workers are exposed to the non-ANSI N13.11 radiation fields, two algorithms for monochromatic radiations (one algorithm was used for various ratios of TL dosimeter and the other for matrix approximation) were developed with the experimental data of the energy responses of the $CaSO_4:Dy$ TL materials irradiated by monochromatic X-ray fields recently established in KAERI, and compared with the another algorithm developed on the basis of the ANSI N13.11 continuous spectrum X-ray fields. Then it follows the discussions for some results of the algorithm testing including mixed fields irradiations and angular response conducted in IAEA/RCA intercomparison as well as ANSI and ISO continuous spectrum X-ray and monochromatic radiation fields. The developed algorithms were successfully performed the test not only in the continuous spectrum X-ray fields given by MOST Ordinance but also in the several non-MOST Ordinance radiation fields which could be encountered in the practical working environments.

• Journal of Radiation Protection and Research
• /
• v.23 no.3
• /
• pp.123-138
• /
• 1998

Characteristics of element responses of Panasonic UD802 personnel dosimeters in the X, ${\beta}$, ${\gamma}$, ${\gamma}/X$, ${\gamma}/{\beta}$ and ${\gamma}$/neutron mixed fields were assessed. A dose-response algorithm has been developed to decide the high probability of a radiation type and energy by using the distribution in all six ratios of the multi-element TLD. To calculate the 4-element response factors and ratios between the elements of the Panasonic TLDs in the X, $\beta$, and $\gamma$ radiation fields, Panasonic’s UD802 TLDs were irradiated with KINS’s reference irradiation facility. In the photon radiation field, this study confirms that element-3 (E3) and element-4 (E4) of the Panasonic TLDs show energy dependent both in low- and intermediate-energy range, while element-1 (E1) and element-2 (E2) show little energy dependency in the entire whole range. The algorithm, which was developed in this study, was applied to the Panasonic personnel dosimetry system with UD716AGL reader and UD802 TLDs. Performance tests of the algorithm developed was conducted according to the standards and criteria recommended in the ANSI N13.11. The sum of biases and standard deviations was less than 0.232. The values of biases and standard deviations are distributed within a triangle of a lateral value of 0.3 in the ordinate and abscissa, With the above algorithm, Panasonic TLDs satisfactorily perform optimum dose assessment even under an abnormal response of the TLD elements to the energy imparted. This algorithm can be applied to a more rigorous dose assessment by distinguishing an unexpected dose from the planned dose for the most practical purposes, and is useful in conducting an effective personnel dose control program.

• Journal of Radiation Protection and Research
• /
• v.20 no.1
• /
• pp.37-44
• /
• 1995

Since provisions on the technical criteria for personnel dosimetry was amended three years ago, several improvements in the technique of monitoring personnel doses by TLD have taken place, but for the photograpfic film as a personnel monitor, additional investigations should be carried out for its accuracy of dose estimates because of its wide use in the radiation involved industries. So, this paper describes the methods to develope dose evaluation algorithm for photographic film using ISO reference radiations by i) empirical formula, ii) degree-of-fit method, and iii) matrix approximation. These methods show a good agreement between irradiated and calculated dose within tolerance level represented in ANSI N13. 11, and can be used for the dose evaluation of X, ${\gamma}$ and/or radiation fields.

• Journal of Radiation Protection and Research
• /
• v.21 no.3
• /
• pp.147-153
• /
• 1996

The Korea Atomic Energy Research Institute(KAERI) conducted a intercomparison study for personnel dosimetry services in Korea to enhance the accuracy and precision of the dosimetry system. Nine types of dosimeters(6 TLD, 3 film badge) from 7 institutions took part in this intercomparison study. Each participant submitted 30 dosimeters including transit control for irradiations. Both TLDs and film badges were irradiated with Cs-137 gamma, Sr/Y-90 beta and 4 X-ray beams in ISO wide series. Four dosimeters were irradiated on phantom with same dose equivalent for each field category. The delivered dose equivalent was in the range of $0.1{\sim}10mSv$. The participants assessed the results of their dosimeter readings in terms of the ICRU operational quantities for personal monitoring, Hp(10) and Hp(0.07). Most participants except 1 dosimeter estimated the delivered dose equivalent with biases less than ${\pm}25%$ for Cs-137 and Sr/Y-90. But for X-rays, the biases exceeded ${\pm}35%$ in some cases bacause the dose evaluation algorithm was based on the ANSI N13.11 X-ray fields which are different from those given by ISO.