natural background radiation

常见例句

This is called natural background radiation.
这称为自然环境辐射。
The committee said the detected levels of radioactive iodine-131 were below one-hundred-thousandth of natural background radiation and not considered harmful.
委员会称此次检测到的碘-131辐射量小于天然本底辐射剂量的十万分之一，不会对公众造成伤害。
For most people more than half of their natural background radiation dose comes from radon, a radioactive gas that can accumulate in homes, schools and workplaces.
对大多数人来说，他们自然环境辐射剂量的一半以上来自氡 — 一种可聚集在家庭、学校和工作场所的放射性气体。
www.pdcdc.sh.cn

Dr. GERBER: It's approximately four times the natural radiation dose that we all receive annually in the Unites States, as a result from background radiation due to radon and other materials.
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