However, if this level cannot be reached under the prevailing country-specific conditions, the reference level should not exceed 300 Bq/m3.

但是，如果在国家现有特定情况下不能达到这一水平，参考水平也不应超过300 Bq/m3。

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Radon concentration in air is measured by the number of transformations per second in a cubic metre of air (Bq/m3)].

空气中氡的浓度按1立方米的空气中每秒转换的数量（Bq/m3）测定] 。

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The risk of lung cancer increases by 16% per 100 Bq/m3 increase in radon concentration.

氡浓度每升高100 Bq/m3，肺癌风险就增加16%。

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