Internal individual dose monitoring and estimation of radiation workers in Beijing

The methods, and results of internal individual dose monitoring of radiation workers in Beijing are reported. 213 workers in 28 laboratories have been monitored, of which 138 workers presented a significant internal contamination. Personal annual committed effective dose equivalent is within the range of 2.2 x 10-3 mSv∼2.2 mSv for the 138 contaminated workers. Collective committed effective dose equivalent is 2.2 x 10-2 man·Sv and the per capita annual committed effective dose equivalent is 9.5 x 10-2 mSv for the 231 workers