指每百万 meaning in English
ppm:parts per million
Examples
- The lta rate is expressed as the ratio of reportable accidents to 1 , 000 , 000 man - hours ? the assumed number of hours worked by one person during a lifetime
事故频度率是指每百万小时发生的伤害事故的频率，它表示在当前的安全生产水平下，一个人在一生的工作时间中可能发生的事故次数。