摘要
用被动式累积探测器在北京房山区史家营(中型煤矿,年产量30万吨)和城关(小型煤矿,年产量3万吨)2座煤矿井下进行了222Rn、220Rn及220Rn子体的测量。测量结果表明,史家营煤矿的222Rn、220Rn年平均浓度和220Rn平衡当量浓度分别为292、90.5和0.9 Bq/m3;城关煤矿的222Rn、220Rn年均浓度和220Rn平衡当量浓度分别为4919、2619和6.0 Bq/m3。由于吸入的222Rn和220Rn及其子体所致矿工人均年有效剂量,史家营煤矿矿工分别为2.54和0.13 mSv;城关煤矿矿工所致相应的人均年有效剂量分别为42.9和1.43 mSv。在这两个煤矿中,222Rn及其子体是矿工受照剂量的主要来源;220Rn及其子体剂量仅占两矿矿工所受总剂量份额的4.9%和3.2%。在通风不好的矿井(如城关矿)222Rn、220Rn浓度的季节变化很大,夏季个别测点222Rn浓度高达1×104Bq.m-3。加强煤矿井下通风,降低矿工的辐射危害是值得关注的问题。
The concentrations of radon and thoron as well as thoron decay products （^220RnD） have been measured by using passive integral monitors in two coal mines of Beijing areas during surmner and winter. The results show that the annual average concentrations of ^222Rn,^220Rn and ^220RnD in two mines were 292 and 4919 Bqm^-3, 91 and 2638 Bqm^-3, 0.9 and 6.0 EEC Bqm^-3, respectively. The average annual effective doses to the miner from radon and thoron were 2.54～42.9 mSv·a^-1 and 0.13 ～ 1.43mSv·a^-1, of which only 4.9 % and 3.2 % of the total doses from thoron. Radon is still the mostly dose source for the miner.
A significant seasonal variation in a coal mine was observed. ^222Rn and ^220Rn concentrations in some sites in surmner exceed 10000Bqm^-3. To heighten ventilation in coal mine is important, in order to avoid the miner exposed to the higher radiation.
出处
《辐射防护》
CAS
CSCD
北大核心
2006年第5期279-285,共7页
Radiation Protection
