초록 ▼

○ 생활주변방사선안전관리법(이하 ‘생방법’)이 시행되어, 천연방사성핵종 함유물질 취급 산업에 대한 관리가 필요함.

○ 하지만, 국내 실정을 반영한 생방법 이행에 필요한 정량적 평가 기초자료가 부족함.

○ 따라서, 본 연구의 목표는 국내 실정에 적합한 피폭선량평가 모델의 개발임.

○ 상기 연구목표의 달성을 위해, 천연방사성핵종 함유물질 취급 사업장(1차년도 : 인광석 및 인산석고, 2차년도 : 석탄연소 발전 및 염화칼륨, 3차년도 : 지르콘 및 보오크사이트)을 대상으로 공정과정 파악, 종사자 근무

○ 생활주변방사선안전관리법(이하 ‘생방법’)이 시행되어, 천연방사성핵종 함유물질 취급 산업에 대한 관리가 필요함.

○ 하지만, 국내 실정을 반영한 생방법 이행에 필요한 정량적 평가 기초자료가 부족함.

○ 따라서, 본 연구의 목표는 국내 실정에 적합한 피폭선량평가 모델의 개발임.

○ 상기 연구목표의 달성을 위해, 천연방사성핵종 함유물질 취급 사업장(1차년도 : 인광석 및 인산석고, 2차년도 : 석탄연소 발전 및 염화칼륨, 3차년도 : 지르콘 및 보오크사이트)을 대상으로 공정과정 파악, 종사자 근무형태 파악, 작업장 방사선량률 측정, 공기 중 분진 농도 및 입자크기 분석 등을 수행하였음.

○ 또한, 천연방사성핵종 함유 공정부산물이 건축자재로 사용됨에 따라 건축자재에 함유되어 있는 천연방사성핵종으로 인한 일반인의 피폭방사선량 평가를 위한 자료를 조사하였으며, 해당 내용을 바탕으로 하여 건축자재로 인한 피폭방사선량 평가 및 방사능 농도지수를 개발하였음.

○ 본 연구 수행결과는, 생활주변방사선 안전관리법에 따른 천연방사성핵종 함유물질의 취급으로 인한 피폭으로부터 국민과 환경을 보호하기 위한 기술자료로 활용될 수 있음.

Abstract ▼

Ⅳ. Research Results

□ Analysis of current status on the industries dealing with NORM
- Before visiting the facilities dealing with NORM, documents are reviewed and collected information from the workers with the interview
- Using the questionnaire, various information such like working

Ⅳ. Research Results

□ Analysis of current status on the industries dealing with NORM
- Before visiting the facilities dealing with NORM, documents are reviewed and collected information from the workers with the interview
- Using the questionnaire, various information such like working time, workplace condition, etc. is achieved
- Based on the information, occupational exposure pathway is developed.

□ Analysis of the pathway on occupational exposure by natural radioactive nuclides in product
- Analysis method of natural radionuclides and proper equipment for measuring natural radionulides were reviewed
- The samples of the facilities using phosphate, coal, potassium chloride, etc. were taken
- The analysis of radioactivity concentration could be done for each industries.

□ Measurement radiation dose rate at workplace and analyze particle characteristics of working area
- The primary location which can be exposed from radiation was selected and measured the amount of radiation dose using the radiation detector considering the distance(contact, 10 cm, 100 cm) from the object : the maximum dose rate is 5.33~5.56 μSv/h at contacting the zircon package
- Particle properties, including particle size distribution, radioactivity, particle shape, and particle density were characterized using cacade impacts, SEM, EDXS, etc.
- As the shape of a particle is granted to the sphere, Shape factor is 1.
- The samples were taken from the facilities and analyzed in order to know the density of the particles

□ Development of the evaluation model on the occupational exposure
- External and Internal exposure assessment was performed for the workers at phosphate and gypsum board industries, coal-fired power plant, potassium chloride industry, zircon and bauxite industries
- In order to evaluate internal exposure dose, dose conversion factor(Sv/Bq), radioactivity concentration of particle(g/m³), respiration rate(m³/h), and annual working time(hr/year) were considered.

□ Development the evaluation model on the public exposure by the building materials
- About 47% of Korean people live in the apartment with area of 84 m²
- Korean people spend 21 hours per day indoor, spend 14 hours in the house, mostly at bed room.
- Radiation dose due to building materials were calculated using MCNP code
- Dose is 0.597 mSv/y for concrete and 0.457 mSv/y for gypsum board
- Considering Korean residential environment, radioactivity concentration index(I) is modified