关于时间加权浓度与有毒物质容许接触水平的算法? The permissible exposure level shall be deemed to have been exceeded if the sum of the ratios between the time weighted average concentration and the permissible exposure level of each substanceexceeds one. 如果时间加权浓度与每种物质容许接触水平之间的比值之和大于1,则认为超过了容许接触水平。 大家看看是否翻译正确? 查看更多1个回答 . 1人已关注