Underground mining yog ib qho kev lag luam uas pheej hmoo heev, uas yog vim li cas ducting yog qhov tseem ceeb ntawm kev lag luam hauv av.Cov mining hauv av nthuav tawm cov neeg ua haujlwm rau ntau yam kab mob, suav nrog cov pa roj carbon monoxide thiab pa taws, uas tuaj yeem ua rau muaj kev phom sij rau lawv txoj kev noj qab haus huv ...
Nyeem ntxiv