background level

基本解釋

The new safety level is about 100 times higher than the background level of dust at ground level.
新的安全水平比地平麪灰塵背景水平高出一百倍，也比從火山爆發(fā)以來(lái)測(cè)試飛機(jī)在英國(guó)上空所測(cè)的數(shù)據(jù)要高很多。
The U.S. Nuclear Regulatory Commission recommends that beyond this background level, the public limit their exposure to less than an additional one millisievert per year.
美國(guó)核琯理委員會(huì)建議，在此背景輻射水平之上，公衆(zhòng)每年可多承受不超過(guò)1毫希的輻射。
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The new safety level is about 100 times higher than the background level of dust at ground level.
新安全標(biāo)準(zhǔn)約是地水準(zhǔn)平麪塵埃本底水準(zhǔn)的100倍，也比自火山噴發(fā)後在英國(guó)領(lǐng)空作科學(xué)研究的飛機(jī)所得的數(shù)據(jù)高很多；

Critics say the national exam is biased, since it presumes a level of knowledge and cultural background that students from working class families may not have.

The new safety level is about 100 times higher than the background level of dust at ground level.
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