Silica can account for over of the respirable dust sample by weight
举一反三
- To effectively control the respirable coal and silica dust exposure of mine workers, it is not necessary to identify the sources of dust generation and quantify the amount of dust liberated by these sources.
- Respirable crystalline silica is defined as particles with aerodynamic diameters less than （ ）microns. A: 10 B: 15 C: 20 D: 25
- over of all dust generated during mining
- When temperature is higher than melting point, ( ) affect(s) water activity. A: sample composition B: sample weight C: sample color D: temperature
- Many practical areas of engineering controls designed to mitigate exposure of surface mine workers to all airborne dusts, including silica, are： A: drill dust collection systems B: enclosed cab filtration systems C: controlling dust on unpaved haulage roads D: controlling dust at the primary hopper dump