natural background radiation

常見例句

This is called natural background radiation.
這稱為自然環(huán)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(huì)稱此次檢測(cè)到的碘-131輻射量小于天然本底輻射劑量的十萬(wàn)分之一，不會(huì)對(duì)公眾造成傷害。
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(duì)大多數(shù)人來(lái)說(shuō)，他們自然環(huán)境輻射劑量的一半以上來(lái)自氡 — 一種可聚集在家庭、學(xué)校和工作場(chǎng)所的放射性氣體。
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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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