natural background radiation

常见例句

This is called natural background radiation.
這稱爲自然環境輻射。
The committee said the detected levels of radioactive iodine-131 were below one-hundred-thousandth of natural background radiation and not considered harmful.
委員會稱此次檢測到的碘-131輻射量小於天然本底輻射劑量的十萬分之一，不會對公衆造成傷害。
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.
對大多數人來說，他們自然環境輻射劑量的一半以上來自氡 — 一種可聚集在家庭、學校和工作場所的放射性氣躰。
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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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