干旱区生态环境知识资源中心

Radiation levels in some working phosphate mines in the Egyptian Eastern Desert have been investigated to estimate the occupational exposure to the workers in those sites. Such results may help in the preparation of the collective actions as well as the improvement of the safety measures if needed in those working mines. Beta and gamma levels as well as radon gas concentration and its decay products have been measured. Active techniques are employed to fulfil the objectives of measuring radon gas and its daughters.

Some working conditions and environmental parameters such as the working time, type of available ventilation, temperature and humidity have been studied during the period of measurements. The maximum reported values for radon daughter concentration in units of working level are 1.28, in Safaga area south mine, 1.22 in Hamraween area B mine and 0.67 in El-Quser area Youns C mine. The maximum annual dose for the worker in all locations under investigation is about 100 mSv/y which is clearly much higher than the recommended international value. According to the above estimated values the question of ventilation economics in such mines is created. The classification of the miners in conventional mines as radiation workers should also be put into consideration.